MT - Densitometria GE DPX NT

Document Information for: LU44246ADW

Type Name Revision State ECO

Description Originator

Drawing Print LU44246ADW 3 Release 2086536 DPX-NT,MD Service Manual 212027348_jennifer_lynn_pakter

File List

1. LU44246ADW_s1_r3.pdf

. s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Approval Information Person 212018997_connie_c_hottman

Action Approved

Date and Time 05/20/2010 2: 2:26:30 PM GMT

212027348_jennifer_lynn_pakter

Approved

05/11/2010 7: 7:39:55 PM GMT

This page is generated automatically by the GEHC MyWorkshop System. System . Pr inted inted documents are for Reference Only and may be out-of-date. Check the database to ensure you have the correct revision.

Approved Document - LU44246ADW_r3.pdf Page 1 of 142

GE Healthcare

DPX-NT and MD+ Service Manual Date: Mar 2010 Part No.: No .: LU44 L U44246 246 Revisi Re visi on 3 ECO 2086536


Headquarters GE Medical Systems Lunar 3030 Ohmeda Drive Madison, WI 53718-6704 USA +1 (800) 437-1171 Europe

GE Medical Systems Systems IT GmbH Munzinger Strasse 3-5 D-79111 Freiburg Germany +49-212-2802 -652 +49-761-4543 -233 (Fax)

Asi a/Pacif ic 4-7-127 Asahigaoka Hino-shi, Tokyo 191-8503 Japan +81-42-585-5111 +81-42-585-3077 (Fax) Germany Beethoven Str. 239 D-42655 Solingen Germany +49-212-2802-0 +49-212-2802-390 (Fax)

China No. 19 Changjiang Road Wuxi, Jiangsu, 214028 P.R.C. +86-510-85225888 +86-510-85226688 (Fax) France GE Healthcare Lunar 11 Avenue Morane Saulnier 78457 Velizy France +33-1-34-49-5365 +33-1-34-49-5406 (Fax)

www.gehealthcare.com

© 2009 by GE Healthcare Approved Document - LU44246ADW_r3.pdf Page 2 of 142

GE Healthcare

DPX-NT and MD+ Service Manual Date: Mar 2010 Part No.: No .: LU44 L U44246 246 Revisi Re visi on 3 ECO 2086536


Headquarters GE Medical Systems Lunar 3030 Ohmeda Drive Madison, WI 53718-6704 USA +1 (800) 437-1171 Europe

GE Medical Systems Systems IT GmbH Munzinger Strasse 3-5 D-79111 Freiburg Germany +49-212-2802 -652 +49-761-4543 -233 (Fax)

Asi a/Pacif ic 4-7-127 Asahigaoka Hino-shi, Tokyo 191-8503 Japan +81-42-585-5111 +81-42-585-3077 (Fax) Germany Beethoven Str. 239 D-42655 Solingen Germany +49-212-2802-0 +49-212-2802-390 (Fax)

China No. 19 Changjiang Road Wuxi, Jiangsu, 214028 P.R.C. +86-510-85225888 +86-510-85226688 (Fax) France GE Healthcare Lunar 11 Avenue Morane Saulnier 78457 Velizy France +33-1-34-49-5365 +33-1-34-49-5406 (Fax)

www.gehealthcare.com

© 2009 by GE Healthcare Approved Document - LU44246ADW_r3.pdf Page 2 of 142


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DPX-NT/MD+ Service Manual (Rev. 3 - 2010)

Revision History


Revision Date

Author

Description

3

Mar 2010

Jennifer Pakter

2

Dec 2010

Jennifer Pakter

1. Updated English Only Disclaimer (added languages since last revision). 2. Added detailed test work instructions to Section 5.6. 3. Removed test grid and referenced LUSE0002 in its place. 4. Updated English Only Disclaimer (added languages since last revision). 5. Updated Sections 1.0 and Chapter 5 to comply with MD. 6. Added NT/MD+ revision information to Section 2.0 7. Added OMD information to Section 2.4.1 8. Removed system labels 9. Updated Appendix

1

Jun 2009

Jennifer Pakter

1. Updated contact information on cover due to facility moves 2. Added English Only disclaimer in multiple languages 3. Updated labels 4. Added appendix that lists associated service documentation. Previous revisions were under part number LU8392 last revision C approved on CO L6631 in Oracle Engineering. Revision History was not recorded in document until Rev. 1.



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This document contains confidential or proprietary information of GE Healthcare. Neither the document nor the information is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Healthcare. GE Healthcare makes no warranty of any kind with regard to this material, and shall not be held liable for errors contained herein or for incidental or consequential damages in connection with the furnishings or use of this manual. Read through this manual thoroughly before attempting to service any components. Unauthorized service may void system warranties or service contracts. Consult the GE Healthcare Customer Support Department prior to attempting any servicing.


WARNING (EN)

This service manual is available in English only. If a customer's service provider requires a language other than english, it is the customer's responsibility to provide translation services. Do not attempt to service the equipment unless this service manual has been consulted and is understood. Failure to heed this warning may result in injury to the service provider, operator or patient from electric shock, mechanical or other hazards.            . (BG)          ,       .   ,          .             ,   a     ,    . 

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(ZH-CN)

       

(ZH-HK)

       

(ZH-TW)

    

   



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UPOZORENJE (HR)

Ovaj servisni prirunik dostupan je na engleskom jeziku. Ako davatelj usluge klijenta treba neki drugi jezik, klijent je dužan osigurati prijevod. Ne pokušavajte servisirati opremu ako niste u potpunosti proitali i razumjeli ovaj servisni prirunik. Zanemarite li ovo upozorenje, može doi do ozljede davatelja usluge, operatera ili pacijenta uslijed strujnog udara, mehanikih ili drugih rizika. Tento provozní návod existuje pouze v anglickém jazyce. V p ípad, že externí služba zákazníkm pot ebuje návod v jiném jazyce, je zajištní p ekladu do odpovídajícího jazyka úkolem zákazníka. Nesnažte se o údržbu tohoto za ízení, aniž byste si p eetli tento provozní návod a pochopili jeho obsah. V p ípad nedodržování této výstrahy mže dojít k poranní pracovníka prodejního servisu, obslužného personálu nebo pacient vlivem elektrického proudu, respektive vlivem mechanických i jiných rizik. Denne servicemanual findes kun på engelsk. Hvis en kundes tekniker har brug for et andet sprog end engelsk, er det kundens ansvar at sørge for oversættelse. Forsøg ikke at servicere udstyret uden at læse og forstå denne servicemanual. Manglende overholdelse af denne advarsel kan medføre skade på grund af elektrisk stød, mekanisk eller anden fare for teknikeren, operatøren eller patienten. Deze onderhoudshandleiding is enkel in het Engels verkrijgbaar. Als het onderhoudspersoneel een andere taal vereist, dan is de klant verantwoordelijk voor de vertaling ervan. Probeer de apparatuur niet te onderhouden alvorens deze onderhoudshandleiding werd geraadpleegd en begrepen is. Indien deze waarschuwing niet wordt opgevolgd, zou het onderhoudspersoneel, de operator of een patiënt gewond kunnen raken als gevolg van een elektrische schok, mechanische of andere gevaren. See teenindusjuhend on saadaval ainult inglise keeles Kui klienditeeninduse osutaja nõuab juhendit inglise keelest erinevas keeles, vastutab klient tõlketeenuse osutamise eest. Ärge üritage seadmeid teenindada enne eelnevalt käesoleva teenindusjuhendiga tutvumist ja sellest aru saamist. Käesoleva hoiatuse eiramine võib põhjustada teenuseosutaja, operaatori või patsiendi vigastamist elektrilöögi, mehaanilise või muu ohu tagajärjel. Tämä huolto-ohje on saatavilla vain englanniksi. Jos asiakkaan huoltohenkilöstö vaatii muuta kuin englanninkielistä materiaalia, tarvittavan käännöksen hankkiminen on asiakkaan vastuulla. Älä yritä korjata laitteistoa ennen kuin olet varmasti lukenut ja ymmärtänyt tämän huolto-ohjeen. Mikäli tätä varoitusta ei noudateta, seurauksena voi olla huoltohenkilöstön, laitteiston käyttäjän tai potilaan vahingoittuminen sähköiskun, mekaanisen vian tai muun vaaratilanteen vuoksi. 

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VÝSTRAHA (CS)

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ADVARSEL (DA) . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

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WAARSCHUWING (NL)

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HOIATUS (ET)

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VAROITUS (FI)

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ATTENTION (FR)

Ce manuel d’installation et de maintenance est disponible uniquement en anglais. Si le technicien d'un client a besoin de ce manuel dans une langue autre que l'anglais, il incombe au client de le faire traduire. Ne pas tenter d'intervenir sur les équipements tant que ce manuel d’installation et de maintenance n'a pas été consulté et compris. Le non-respect de cet avertissement peut entraîner chez le technicien, l'opérateur ou le patient des blessures dues à des dangers électriques, mécaniques ou autres. Diese Serviceanleitung existiert nur in englischer Sprache. Falls ein fremder Kundendienst eine andere Sprache benötigt, ist es Aufgabe des Kunden für eine entsprechende Übersetzung zu sorgen. Versuchen Sie nicht diese Anlage zu warten, ohne diese Serviceanleitung gelesen und verstanden zu haben. Wird diese Warnung nicht beachtet, so kann es zu Verletzungen des Kundendiensttechnikers, des Bedieners oder des Patienten durch Stromschläge, mechanische oder sonstige Gefahren kommen.        .               ,         .                  .      ,       ,       ,    . Ezen karbantartási kézikönyv kizárólag angol nyelven érhet el. Ha a vev szolgáltatója angoltól eltér  nyelvre tart igényt, akkor a vev felelssége a fordítás elkészíttetése. Ne próbálja elkezdeni használni a berendezést, amíg a karbantartási kézikönyvben leírtakat nem értelmezték. Ezen figyelmeztetés figyelmen kívül hagyása a szolgáltató, mködtet vagy a beteg áramütés, mechanikai vagy egyéb veszélyhelyzet miatti sérülését eredményezheti. Þessi þjónustuhandbók er aðeins fáanleg á ensku. Ef að þjónustuveitandi viðskiptamanns þarfnast annas tungumáls en ensku, er það skylda viðskiptamanns að skaffa tungumálaþjónustu. Reynið ekki að afgreiða tækið nema að þessi þjónustuhandbók hefur verið skoðuð og skilin. Brot á sinna þessari aðvörun getur leitt til meiðsla á þjónustuveitanda, stjórnanda eða sjúklings frá raflosti, vélrænu eða öðrum áhættum. Il presente manuale di manutenzione è disponibile soltanto in lingua inglese. Se un addetto alla manutenzione richiede il manuale in una lingua diversa, il cliente è tenuto a provvedere direttamente alla traduzione. Procedere alla manutenzione dell'apparecchiatura solo dopo aver consultato il presente manuale ed averne compreso il contenuto. Il mancato rispetto della presente avvertenza potrebbe causare lesioni all'addetto alla manutenzione, all'operatore o ai pazienti provocate da scosse elettriche, urti meccanici o altri rischi. 

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WARNUNG (DE)

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 . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

(EL)

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FIGYELMEZTETÉS (HU)

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AÐVÖRUN (IS)

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AVVERTENZA (IT)

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   

(JA)

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 

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 

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  

(KO)

       . 

        ,       .

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           .

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       ,  ,       ,        .


R  DINJUMS (LV)

Š  apkopes rokasgr mata ir pieejama tikai ang u valod. Ja klienta apkopes sniedz jam nepieciešama informcija cit valod, klienta pienkums ir nodrošint tulkojumu. Neveiciet apr  kojuma apkopi bez apkopes rokasgr matas izlas  šanas un saprašanas. Š  br  din juma neievrošanas rezultt var rasties elektrisks str vas trieciena, mehnisku vai citu faktoru izrais  tu traumu risks apkopes sniedz jam, operatoram vai pacientam. Šis eksploatavimo vadovas yra tik angl kalba. Jei kliento paslaug tiek jas reikalauja vadovo kita kalba – ne angl, suteikti vertimo paslaugas privalo klientas. Nemginkite atlikti  rangos technins priežiros, jei neperskaitte ar nesupratote šio eksploatavimo vadovo. Jei nepaisysite šio  sp jimo, galimi paslaug tiek jo, operatoriaus ar paciento sužalojimai dl elektros šoko, mechanini ar kit pavoj . Denne servicehåndboken finnes bare på engelsk. Hvis kundens serviceleverandør har bruk for et annet språk, er det kundens ansvar å sørge for oversettelse. Ikke forsøk å reparere utstyret uten at denne servicehåndboken er lest og forstått. Manglende hensyn til denne advarselen kan føre til at serviceleverandøren, operatøren eller pasienten skades på grunn av elektrisk støt, mekaniske eller andre farer. Niniejszy podr cznik serwisowy dostpny jest jedynie w jzyku angielskim. Jeli serwisant klienta wymaga jzyka innego ni angielski, zapewnienie usugi tumaczenia jest obowi zkiem klienta. Nie próbowa serwisowa urz dzenia bez zapoznania si z niniejszym podr cznikiem serwisowym i zrozumienia go. Niezastosowanie si do tego ostrzeenia moe doprowadzi do obrae serwisanta, operatora lub pacjenta w wyniku poraenia pr d em elektrycznym, zagroenia mechanicznego b d innego. 

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SPJIMAS (LT)

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ADVARSEL (NO)

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OSTRZEENIE (PL)

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Page 8 of 141



AVISO (PT-BR)

Este manual de assistência técnica encontra-se disponível unicamente em inglês. Se outro serviço de assistência técnica solicitar a tradução deste manual, caberá ao cliente fornecer os serviços de tradução. Não tente reparar o equipamento sem ter consultado e compreendido este manual de assistência técnica. A não observância deste aviso pode ocasionar ferimentos no técnico, operador ou paciente decorrentes de choques elétricos, mecânicos ou outros. Este manual de assistência técnica só se encontra disponível em inglês. Se qualquer outro serviço de assistência técnica solicitar este manual noutro idioma, é da responsabilidade do cliente fornecer os serviços de tradução. Não tente reparar o equipamento sem ter consultado e compreendido este manual de assistência técnica. O não cumprimento deste aviso pode colocar em perigo a segurança do técnico, do operador ou do paciente devido a choques eléctricos, mecânicos ou outros. Acest manual de service este disponibil doar în limba englez. Dac un furnizor de servicii pentru clieni necesit o alt limb decât cea englez, este de datoria clientului s furnizeze o traducere. Nu încercai s reparai echipamentul decât ulterior consultrii i înelegerii acestui manual de service. Ignorarea acestui avertisment ar putea duce la r nirea depanatorului, operatorului sau pacientului în urma pericolelor de electrocutare, mecanice sau de alt natur .          .         ,   -  ,     .               .        ,     ,       ,     . Ovo servisno uputstvo je dostupno samo na engleskom jeziku. Ako klijentov serviser zahteva neki drugi jezik, klijent je dužan da obezbedi prevodilake usluge. Ne pokušavajte da opravite ureaj ako niste proitali i razumeli ovo servisno uputstvo. Zanemarivanje ovog upozorenja može dovesti do povreivanja servisera, rukovaoca ili pacijenta usled strujnog udara ili mehanikih i drugih opasnosti. Tento návod na obsluhu je k dispozícii len v anglitine. Ak zákazníkov poskytovate služieb vyžaduje iný jazyk ako anglitinu, poskytnutie prekladateských služieb je zodpovednosou zákazníka. Nepokúšajte sa o obsluhu zariadenia, kým si nepreítate návod na obluhu a neporozumiete mu. Zanedbanie tohto upozornenia môže spôsobi zranenie poskytovatea služieb, obsluhujúcej osoby alebo pacienta elektrickým prúdom, mechanické alebo iné ohrozenie. 

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ATENÇÃO (PT-PT)

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ATENIE (RO) . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

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! (RU)

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UPOZORENJE (SR)

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UPOZORNENIE (SK)

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Page 9 of 141

ATENCION (ES)

Este manual de servicio sólo existe en inglés. Si el encargado de mantenimiento de un cliente necesita un idioma que no sea el inglés, el cliente deberá encargarse de la traducción del manual. No se deberá dar servicio técnico al equipo, sin haber consultado y comprendido este manual de servicio. La no observancia del presente aviso puede dar lugar a que el proveedor de servicios, el operador o el paciente sufran lesiones provocadas por causas eléctricas, mecánicas o de otra naturaleza. Den här servicehandboken finns bara tillgänglig på engelska. . Om en kunds servicetekniker har behov av ett annat språk än engelska, ansvarar kunden för att tillhandahålla översättningstjänster. Försök inte utföra service på utrustningen om du inte har läst och förstår den här servicehandboken. Om du inte tar hänsyn till den här varningen kan det resultera i skador på serviceteknikern, operatören eller patienten till följd av elektriska stötar, mekaniska faror eller andra faror. 

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VARNING (SV)

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OPOZORILO (SL)

Ta servisni prironik je na voljo samo v angleškem jeziku. e ponudnik storitve stranke potrebuje prironik v drugem jeziku, mora stranka zagotoviti prevod. Ne poskušajte servisirati opreme, e tega prironika niste v celoti prebrali in razumeli. e tega opozorila ne upoštevate, se lahko zaradi elektrinega udara, mehanskih ali drugih nevarnosti poškoduje ponudnik storitev, operater ali bolnik. 

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DKKAT (TR)

Bu servis kılavuzunun sadece ingilizcesi mevcuttur. Eer müteri teknisyeni bu kılavuzu ingilizce dıında bir baka lisandan talep ederse, bunu tercüme ettirmek müteriye düer. Servis kılavuzunu okuyup anlamadan ekipmanlara müdahale etmeyiniz. Bu uyarıya uyulmaması, elektrik, mekanik veya dier tehlikelerden dolayı teknisyen, operatör veya hastanın yaralanmasına yol açabilir. 

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READ THIS FIRST Using This Manual A person who will be performing service work on the DPX-NT / MD+ should use this manual in the following manner: Read the Safety and Overview Chapters to familiarize yourself with the scanner as a whole and with the genera lfunction of the circuit boards. Chapter 3 should be understood completely as it explains the Diagnostics Software (built in – requires a password for access). . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The Chapter 4 and Chapter 5 contain common procedures and troubleshooting information and can be read as needed, but are good sources of information. When a problem arises, Chapter 4 should be referenced. Check the table of contents for Chapter 4 to see if the problem being experienced is described. If so, refer to the appropriate page. If not, try to generalize the problem (e.g. the Detector is repeatedly running into the front of the scanner and reversing and then running back into the front of the scanner. This is a mechanical problem in general, specifically with Transverse Mechanics, check that subsection of Chapter 4 for the subsystem experiencing the fault. This manual commonly references other Sections and pages of the manual as needed, so often procedures in the Chapter 5 and the Appendix are referred to as ways to solve problems described in Chapter 4.



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Page 12 of 141



Table of Contents Chapter 1: Safety


1.0 General Safety 1.1 Symbols and labels found on the DPX-NT / MD+ 1.2 Emergency Stop Button 1.3 Laser Exposure 1.4 Shutter Indicator 1.5 Cautions, Warnings, and Notes 1.6 Safety Concerns 1.7 Scatter Radiation 1.8 Controlling Computer and Accessories 1.9 Peripheral configurations

15 17 18 22 23 24 24 25 26 29 29

Chapter 2: System Overview 2.0 DPX-NT / MD+ System 2.1 Electronics 2.2 DPX-NT / MD+ Block Diagrams 2.3 DPX-NT / MD+ Fusing 2.4 Combined Single Board Controller cSBC 2.5 X-ray Source 2.6 Display Panel 2.7 High Voltage Power Supplies 2.8 D-MAX Board (DPX-NT (A) ONLY) 2.9 XORB Board (DPX-NT (A) ONLY) 2.10 Detector Sub System 2.11 X-Ray Collimator Subsystem 2.12 DPX-NT / MD+ Specifications 2.13 Secondary Calibration / Daily QA

33 37 38 40 43 43 61 62 63 63 63 64 64 65 76

Chapter 3: Service Software 3.0 Diagnostic Software 3.1 The Tools Menu DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


81 83 84 Page 13 of 141

3.2 Tools / Diagnostics Menu 3.3 Diagnostic Scan Modes 3.4 Error Log 3.5 Service Options

85 88 88 93

Chapter 4: Troubleshooting


95

4.0 Diagnostic Failure Codes 4.1 Transverse Motion failure 4.2 Longitudinal Motion failure 4.3 Failure of the DC Power Supply 4.4 Emergency Stop Button 4.5 Tube Head Thermostat 4.6 Communication Error 4.7 Other Diagnostic Failure Codes 4.8 Failing Quality Assurance Test 4.9 Reference Counts 4.10 Arcing 4.11 Imaging Problems 4.12 Failing Alignment Test Results 4.13 Indicator Failures 4.14 Communications Failures 4.15 Viewing Quality Assurance Trends 4.16 MAX Board Troubleshooting 4.17 OMI/OMD Board Troubleshooting 4.18 SBC Troubleshooting 4.19 XORB Troubleshooting

97 97 100 104 104 105 105 105 106 109 112 114 116 118 120 120 121 122 122 123

Chapter 5: Service Procedures

125

5.0 Reloading LUNAR Software 5.1 Peaking the Detector 5.2 Tube Head Replacement 5.3 Lower Cable Bundle Replacement 5.4 Upper Cable Bundle Replacement 5.5 Tube Head Control Cable Replacement 5.6 Tests to Perform after Service

127 127 128 129 132 134 137

Appendix: Associated Service Documentation

Page 14 of 141


141


1

Safety This chapter highlights safety devices and features a Service Engineer should know before servicing a DPX-NT / MD+ system. Chapter Contents:


1.0 General Safety 1.1 Symbols and labels found on the DPX-NT / MD+ 1.1.1 Symbols 1.1.2 Labels 1.2 Emergency Stop Button 1.3 Laser Exposure 1.4 Shutter Indicator 1.5 Cautions, Warnings, and Notes 1.5.1 Caution Statements 1.5.2 Warning Statements 1.5.3 Note Statements 1.6 Safety Concerns 1.7 Scatter Radiation 1.8 Controlling Computer and Accessories 1.8.1 Electrical Safety 1.9 Peripheral configurations 1.9.1 Standard room configuration 1.9.2 Small room configuration Figure 1-1. The DPX-NT / MD+ Display Panel Figure 1-2. Laser Warning Label (All systems except Canada) Figure 1-3. Laser Warning Label (Canadian Systems only) Figure 1-4. Laser Warning Symbol (on display panel) Figure 1-5. Source (x-rays) off - Shutter closed (green) Figure 1-6. Source (x-rays) on - Shutter S hutter open (yellow) Figure 1-7. Potential Pinch Points on the DPX-NT / MD+ Figure 1-8. DPX-NT Iso-Dose Diagram Figure 1-9. DPX-MD+ Iso-Dose Diagram DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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1.0 General Safety 

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DO NOT attempt to service the DPX-NT / MD+ without first reading this manual. DO NOT attempt any repairs without prior instructions from authorized LUNAR personnel. In order to maintain electrical safety and electromagnetic compatibility, the Lunar DPX-NT / MD+ is only to be connected to a computer, printer, and peripherals that meet IEC requirements for safety, such as IEC 950/ EN 60950 - “Safety of information technology equipment, including electrical business equipment” and IEC 601-1-2 - “Medical electrical equipment”, Part 1: General requirements for safety, 2. Collateral Standard: Electromagnetic compatibility - Requirements and tests. Ionizing Radiation: Exposure: When power is applied, this equipment may generate ionizing radiation. Take precautions that no part of the body passes through the x-ray beam when the equipment is energized. Avoid scatter scatter radiation during warm-up and testing by maintaining a safe distance from the x-ray beam. See the Safety and Specification manual for equipment appropriate distance and other precautions regarding ionizing radiation. All operators must be properly trained regarding ionizing radiation and take adequate steps to protect against injury. Electric Shock: This equipment contains high voltages. When the tabletop/panels/ shrouds are removed, visually confirm that power cord is unplugged and remains unplugged until power is required to complete the procedure. When servicing while energized, take precautions to prevent electric shock. Moving Parts and Pinch Points: Avoid moving parts and pinch points (e.g. belt/pulley, arm/back rail, green wheels/rail). Sharp Edges: Take precautions to prevent injury from contact with component edges (e.g. OMI/OMD wheel, arm slot cover). Hot Surfaces: Keep hands clear or allow components to cool before servicing. (e.g. stepper motors, hard drives, power supplies and microprocessors). Heavy Lifting: Obtain help lifting or moving any object weighing over EHS limits. Ask for assistance when maneuvering awkward objects (e.g. tabletop). Laser Radiation: Do not stare into the laser laser beam at any time. The reflection from the tabletop or shutter/collimator assembly is sufficient to determine if the laser is on. Follow appropriate Lockout/Tagout procedures as described in MyLearning training course GEMS-EHS-LOTOAth. Wear appropriate PPE (Personal Protective Equipment) while servicing the equipment, e.g. eye protection and steel-toe/compositetoe shoes.



Page 17 of 141

1.1 Symbols and labels found on the DPX-NT / MD+ 1.1.1 Symbols 

The following symbols are found on the DPX-NT / MD+, in the Operators manual, and in the Service Manual.

Attention: contains important safety information such as the location of a pinch point.

Emergency Stop Button: shows the location of the emergency stop button. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Power On: shows the location of the Power On indicator.

Laser On: shows the location of the Laser On indicator.

Page 18 of 141



Shutter Open: shows the location of the Shutter Open indicator.

X-ray On: shows the location of the X-Ray On indicator.

Type B Equipment: shows that the scanner has Type B protection against electrical shock. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Protective Earth: shows the location of a protective earth terminal.

Functional Earth: shows the location of a functional earth terminal.

1.1.2 Labels • The following labels are found on the DPX-NT / MD+ Scanner.

Laser Caution Label: Shows that the scanner uses a Class II laser.

Laser Caution Label: Canada only



Page 19 of 141

Tube Head Assembly Label (All DPX-MD+ and DPX-NT System Number 72000 and higher): This label gives tube head assembly and xray source characteristics information. It is located on the tube head assembly and the foot panel of the scanner.


Tube Head Assembly Label (DPXNT System Number 71999 and lower): This label gives tube head assembly and x-ray source characteristics information. It is located on the tube head assembly and the foot panel of the scanner.

A definition of each symbol on this label follows:

Inherent Filtration

Tube Insert

X-ray Source

Focal Point

High Voltage Power Supply: This label gives high voltage power supply (x-ray generator) information. It is located on the high voltage power supply(s), and foot panel of the scanner.

Page 20 of 141



X-ray Controller: This label shows x-ray controller compliance. It is located on the foot panel of the scanner.

Collimator Assembly: This label gives collimator assembly information. It is located on the collimator and foot panel of the scanner. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Warning Label and Radiation Symbol: The Warning label shows that the system uses ionizing radiation. It is found only on systems delivered in the United States. Always obey instructions for safe operation.

Radiation Label: This label shows that the system uses ionizing radiation.



Page 21 of 141

Grounding Reliability Label: This label states that grounding reliability can only be maintained when using a “Hospital Grade” or “Hospital Only” receptacle. It is only found on systems delivered in the United States.

Note:


When replacing a certified component (x-ray controller, x-ray tube head, collimator or high voltage power supply(s)) also install the duplicate certified component label (supplied with the repalcement certified component) on the foot end panel of the scanner. The label for the new part should be palced directly over the laber for the part it is replacing. Refer to DXSE3001 DPX-NT / MD+ Label Replacement Procedure (Chapter 5Appendix I - this manual) for specific instructions.

1.2 Emergency Stop Button • The Emergency Stop Button is located on the front of the scan arm of the DPX-NT / MD+ scanner (see Figure 1-1). When pressed, power is removed from the X-ray tube head, the laser, and the shutter is closed. Power is also removed from the scan arm motors, allowing the operator/ patient to push the scan arm out of the way.

Figure 1-1. The DPX-NT / MD+ Display Panel

Page 22 of 141



1.3 Laser Exposure • The DPX-NT / MD+ is equipped with a Class II Laser device. This laser is used for patient positioning. A Class II rating indicates a low power visible laser that is not normally hazardous to eyesight but has the potential to be hazardous if viewed directly for an extended period of time. Because of this potential hazard, DO NOT stare directly into the beam while the laser is in operation, and DO NOT allow the beam to shine directly into the patients' eyes. No specific eye protection is required with a Class II laser.


• A amber laser-on indicator, located on the front of the scan arm, is lit when the laser is on. The program activates the laser during positioning for an image acquisition. The program then turns off the laser when you begin the scan. The emergency stop button will turn off the laser. • There is a caution label (Figure 1.2) on the scan arm near the Display Panel.

Figure 1-2. Laser Warning Label (All systems except Canada)

Figure 1-3. Laser Warning Label (Canadian Systems only)

Figure 1-4. Laser Warning Symbol (on display panel) Note:

DO NOT STARE INTO THE BEAM while the laser is operating.



Page 23 of 141

1.4 Shutter In Indicator • This symbol symbol is used to indicate indicate aann open-shutter open-shutter condition condition in acco accordance rdance with the safety standards established by the International Electrotechnical Commission (IEC).

Figure 1-5. Source (x-rays) off - Shutter closed (green) . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Figure 1-6. Source (x-rays) on - Shutter open (yellow)

• This symbol symbol appea appears rs near near the yellow yellow X-ray shutte shutter-open r-open indicator indicator light. light. The X-ray shutter-open indicator light is located on the Display Panel on the scan arm near the front. Note:

When the the x-ray x-ray on on / shutter shutter open symbol symbol appears appears in litera literature ture associated with the DPX-NT / MD+ scanner, it will be used to indicate that the procedure being described results in an openshutter condition. During these times personnel should exercise caution to avoid excessive exposure to the X-rays.

1.5 Cau auti tion ons, s, Warni arnin ngs gs,, aand nd Note Notess • This manual contains contains warning warning and caution caution statemen statements ts whereve whereverr appropriate for your safety. The warnings and cautions used throughout the manual are based on the safety standards established by the International Electrotechnical Commission (IEC). In addition, the manual uses notes to attract the reader's attention to important information.

1.5.1 Caution Statements A caution statement reflects a condition that, if not avoided, could cause equipment or property damage.

Page 24 of 141



1.5.2 Warning Statements A warning statement reflects a potentially hazardous condition that, if not avoided, could result in serious injury.

1.5.3 Note Statements Note:


This symbol symbol turns turns the reader's reader's attention attention to important important information which may otherwise be overlooked.

1.6 Safety Co Concerns Because the DPX-NT / MD+ Densitometer contains moving parts, there are places on the scanner where there is a danger of p inching. Operators should be aware of these pinch points to avoid injury to the patient or themselves. Labels applied at the LUNAR factory indicate the location of the pinch points. The pinch points and their labels are shown in the figure 1-7.

Figure 1-7. Potential Pinch Points on the DPX-NT / MD+



Page 25 of 141

DO NOT touch live components on the DC power supply - when the cover is off of the supply some components (such as the heat sinks) are at line voltage and present a shock hazard

1.7 Scatter Radiation . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• There is some some scatter scatter radiation radiation from from the DPX-NT / MD+ when when itit is running. Figure 1-8 shows the radiation dosages while the scanner is running at 1.50 mA at certain distances. • These dosag dosages es are relatively relatively insigni insignificant ficant as the allowed allowed yearly yearly dosage dosage for a person working with radiation emitting equipment is 5000 mRem. Radiation however should be avoided when possible.

Page 26 of 141




Figure 1-8. DPX-NT Iso-Dose Diagram



Page 27 of 141


Figure 1-9. DPX-MD+ Iso-Dose Diagram

Page 28 of 141



1.88 Cont 1. Contro roll llin ing g Com Compu pute terr and and Acce Access ssor orie iess 1.8.1 Electrical Safety • IEC and and UL/ UL/CS CSA A certi certific ficat ation ion Note:


Not all all scanner scanners s produced produced are built built to to IEC / UL / CSA standards - IEC / UL / CSA compliant scanners bear the appropriate mark on the foot end panel when the scanner was produced and shipped in its compliant compliant form

IEC: To To maintain electrical safety, all computer equipment and accessories connected to the scanner must meet IEC standards for safety, such as IEC 950, “Safety of information technology equipment, including electrical business equipment,” and IEC 801-5, “EMC Surge Immunity Requirements.” The computer and all accessories must have “CE” labels. UL/CSA: To To maintain electrical safety, all computer equipment and accessories connected to the scanner must have saftey agency approvals fo UL/CSA and comply with these standards.

See Operators manual for host computer / peripheral configurations

1.99 Per 1. Perip iphe hera rall co conf nfig igur uraation tionss

The correct connection of the computer and all peripherals is necessary to maintain electrical safety. The signal cable of the scanner is intended only for connection to an approved computer. Call LUNAR Support or your LUNAR distributor before adding peripherals.

1.9.1 Standard room configuration



Page 29 of 141

The computer, peripherals, and all other equipment must be located more than 1.83 m from the scanner. Use an outlet strip to power the computer and all peripherals.

The outlet strip must be mounted off the floor so that it does not touch other equipment. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

0If the outlet strip was provided by LUNAR, it has a maximum output of 15A, 120VAC. Only system-related equipment should be powered by the outlet strip. A modem and/or network connection can be made at any time if you are using the standard room configuration.

1.9.2 Small room configuration

The computer, peripherals, and all other equipment must be powered with an isolating transformer if the room is too small to maintain at least 1.83 m of separation between the scanner and all other equipment. The isolation transformer supplied by LUNAR (part number 8544) has a maximum output of 400/500VA. 400/500VA.

Only system-related equipment should be powered by the isolation transformer. Failure to use an isolation transformer can cause leakage currents in excess e xcess of 100 microamperes.

Page 30 of 141



A modem and/or network connection can only be made in the small room configuration if all exposed metal surfaces of the computer and peripherals are out of the patient environment.




Page 31 of 141



Page 32 of 141



2

System Overview

This chapter provides an overview of the DPX-NT / MD+ system. • In addition the chapter contains a brief discussion of major subsystems. • This Chapter contains the DPX-NT / MD+ Block Diagrams


2.0 DPX-NT / MD+ System 2.0.1 DPX-NT / MD+ Electronics 2.1 Electronics 2.1.1 Electronics Pan 2.1.2 Power specifications 2.2 DPX-NT / MD+ Block Diagrams 2.2.1 DPX-NT (A) Systems (71999 and lower) Power Distribution Block Diagram (AC entrance) 2.2.2 DPX-NT (A) System (71999 and lower) Block Diagram 2.2.3 DPX NT(B) / MD+ (systems 72000 and higher) Block Diagram 2.3 DPX-NT / MD+ Fusing 2.4 Combined Single Board Controller cSBC 2.4.1 Motion Control 2.4.2 Patient Positioners 2.4.3 X-ray Source Control 2.4.4 Shutter / Collimator Drive 2.4.5 End of Exposure Alarm 2.4.6 Panel LED's 2.4.7 HVPS Control 2.4.8 ADC 2.4.9 mA Low Range 2.4.10 Detector Interface 2.4.11 Comparators and Reference DAC's 2.4.12 Bias Control 2.4.13 Communications Ports 2.4.14 Diagnostic LED's 2.4.15 Laser Control 2.4.16 Power Distribution 2.5 X-ray DPX-NT/MD+ Service Manual (Rev. 3 Source - 2010) Page 33 of 141 Approved Document - LU44246ADW_r3.pdf Page 34 of 142


2.5.1 X-ray generation and Spectrum 2.6 Display Panel 2.7 High Voltage Power Supplies 2.8 D-MAX Board (DPX-NT (A) ONLY) 2.8.1 D-MAX Board Function 2.9 XORB Board (DPX-NT (A) ONLY) 2.10 Detector Sub System 2.10.1 Detector Overview 2.11 X-Ray Collimator Subsystem 2.12 DPX-NT / MD+ Specifications 2.12.1 Component specifications 2.12.2 Functional specifications 2.12.3 Maximum scan area (long x transverse) 2.12.4 Programs 2.12.5 Environmental specifications 2.12.6 Storage and transport environment 2.12.7 X-ray generator specifications 2.12.8 LUNAR 8548 and 8297 X-ray tube housing assemblies 2.12.9 Laser specifications 2.12.10 Compatible components 2.12.11 FDA certified components (US only) 2.13 Secondary Calibration / Daily QA 2.13.1 Secondary Calibration overview 2.13.2 Starting the Daily QA (secondary calibration) 2.13.3 Peak Test 2.13.4 Functional Tests 2.13.5 Reference Value Test 2.13.6 Tissue Value Test 2.13.7 BM Chamber Measurements 2.13.8 Daily QA Results 2.13.9 QA Database

Page 34 of 141

Figure 2-10. DPX-NT (A) Systems (71999 and lower) Power Distribution Block Diagram Figure 2-11. DPX-NT (A) Systems (71999 and lower) System Block Diagram Figure 2-13. DPX-NT / MD+ display panel Figure 2-14. Reference axis and target angles for tube housing assembly head assembly Figure 2-15. Anode heating/cooling curves Figure 2-16. Cathode emission characteristics DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Figure 2-17. X-ray tube assembly heating / cooling curves


Table 2-1. DPX-NT / MD+ FUSING Table 2-2. Component specifications Table 2-3. LUNAR 7681 X-ray generator technical information (system no. 72000 and higher) Table 2-4. LUNAR 0311 / 0312 or 8531 / 8532 X-ray generator technical information (NT (A) Systems numbered 71999 and lower) Table 2-5. LUNAR 8022 X-ray tube technical information Table 2-6. LUNAR 8548 x-ray tube head assembly (DPX-NT (B) and MD+ systems numbered 72000 and higher) technical information Table 2-7. LUNAR 8297 x-ray tube housing assembly (DPX-NT (A) systems 71999 and lower) technical information Table 2-8. Laser specifications Table 2-9. FDA certified components (DPX-NT and MD+ Systems number 72000 and greater) Table 2-10. FDA certified components (DPX-NT Systems number 71999 and lower)



Page 35 of 141



Page 36 of 141



2.0 DPX-NT / MD+ System The DPX-NT / MD+ includes the patient table and frame, detector, and arm. Its physical specifications are summarized in section 2.12.1 The physical and technical specifications of each system are summarized in sections 2.7 and 2.12.7 The DPX-NT has been built as 4 different generations:


Product Line DPX NT/MD+ Full A DPX NT/MD+ Full B DPX NT/MD+ Compact B DPX NT/MD+ Full C DPX NT/MD+ Compact C DPX NT/MD+ Full E DPX NT/MD+ Compact E

First Serial Number 70001 72000 90001 73001 91001 150001 160001

First System ID Number NT+70000 NT+72000 NT-90101 NT+73000 NT-91000 NT+150001 NT-160001

Hardware differences between generations are as follows. Assume all other hardware is the same as the previous generation: NTA 

3 Printed circuit boards in the electronics pan



Positive and Negative High Voltage Power Supply (HVPS)

NTB 

1 printed circuit board in the electronics pan



New X-Ray generator, tube housing assembly and cabling



Integrated HVPS, new HV cables, new cSBC, new DC power supply



Introduction of MD+ feature set

NTC 

Centent motor controller replaced by Gecko



Bertan bias supply replaced by custom board



New laser and mount



New color scheme

NTE 





New transverse and longitudinal motor assembly combines motor controller and motor. New idler assembly, drive pulley, drive belts, cSBC to motor cables and belt clamps. Mid-generation cut-over to dark blue washable table pads.



Page 37 of 141

The DPX-NT generations have a common mechanical design with two separate motion systems that are capable of simultaneous operation. These are transverse, and longitudinal. Alll motion systems are driven by stepper motors. Most instructions in this manual apply to all of the DPX NT generations. Where differences apply - they will be noted.

2.0.1 DPX-NT / MD+ Electronics The internal components of the scanner are safely secured by a number of panels, including the scanner's tabletop.




The lower front and side panels are secured by locks.



The rear panel is secured by screws from the outside.



The table top is screwed down inside.

Note: Primary Service access to the electronics of the scanner is through the table top. 



The Detector electronics (in the scan arm) are secured by an upper and lower shroud, held in place by screws. Each metal panel is grounded to the electronics pan.

It is not usually necessary to remove the front and back panels for most service needs. However, if access is needed to the Front and Rear Longitudinal Carriages, these can be removed. The back panel is secured by hex socket head-head screws and must be slid out of the way, for it is between the Arm Column and the frame. If access is needed to the detector, Transverse Limit Switches or the other components mounted above in the arm, the covers of the arm must be removed. 



The lower arm shroud is held in place by four screws, and must be removed prior to removing the upper scan arm shroud The upper scan arm shroud can be removed by loosening the two screws holding it in place (on the back of the arm column) and tipping it forward.

2.1 Electronics 2.1.1 Electronics Pan The electronic components of the DPX-NT / MD+ are mounted on the grounded Electronics Pan which is horizontally fastened inside the frame. 



There is one switchable low voltage DC power supply (all outputs under 30VDC), and one (DPX-NT (B) / MD+) or two (DPX-NT (A)) high-voltage DC power supplies (x-ray generator, to supply 76kV to the x-ray tube housing assembly) on the pan. One high-voltage DC power supply (1000VDC) is located in the upper arm near the X-ray detector and provides power to the Detector.

Page 38 of 141





In addition to the power supplies, the electronics mounting chassis holds one (DPX-NT (B) / MD+) or three (DPX-NT (A)) printed circuit boards, a stepper motor controller, and an AC entrance/line filter/fuse holder (see appendix 2A for cSBC schematic, see appendix 2B for AC Entrance wiring diagrams).

2.1.2 Power specifications Leakage current • Total System with Isolation Transformer: <100 microamperes. The isolation transformer supplied by LUNAR has a maximum output of 400/500VA. Only system-related equipment should be powered by the isolation transformer. Failure to use an isolation transformer can cause leakage currents in excess of 100 microamperes . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• Scanner Table alone: <100 microamperes.

Scanner input power 



The scanner is capable of accepting AC inputs between 100 and 254 VAC. The scanner’s low voltage DC power supply automatically configures itself for the voltage on site. Voltage may fluctuate ±10% from the nominal value without a loss of scanner performance.



The nominal input (range of inputs) can be found on the system label.



The rated power input is 1500 VA.



Page 39 of 141

2.2 DPX-NT / MD+ Block Diagrams The block diagrams for the DPX-NT / MD+ system follow:

2.2.1 DPX-NT (A) Systems (71999 and lower) Power Distribution Block Diagram (AC entrance)


Page 40Figure of 141

2-10. DPX-NT (A) Systems (71999 and lower) Power DPX-NT/MD+ DistributionService BlockManual Diagram (Rev. 3 - 2010)


2.2.2 DPX-NT (A) System (71999 and lower) Block Diagram


DPX-NT/MD+ Service Manual 3 -DPX-NT 2010) Figure(Rev. 2-11.

Page 41 of 141 (A) Systems (71999 and lower) System Block Diagram


2.2.3 DPX NT(B) / MD+ (systems 72000 and higher) Block Diagram


Page 42 of 141



Figure 2-12. DPX-NT (B) and MD+ (systems numbered 72000 and greater) Block and Power Diagram

2.3 DPX-NT / MD+ Fusing Table 2-1. DPX-NT / MD+ FUSING


Fuse

Rating

Type

Condor PS F1

F3.15 AH

5x20 mm

Condor PS F2

F3.15 AH

5x20 mm

Condor PS F3

F3.15 AH

5x20 mm

MAX PCB F1 (NT (A) Systems 71999 and lower only)

F0.5 AL

1/4 x 1 1/4 in

All Fuses are 250V

2.4 Combined Single Board Controller cSBC The cSBC printed wiring board (PWB) is an eight layer rectangular board measuring 7.400" x 8.100". The board thickness is specified as 0.093" (standard is 0.062") to increase stiffness and stability for cable insertion. The PWB is mounted in the via four mounting holes located 1/4" from each corner and 2 additional interior mounting holes. The components are primarily surface mount, with board connectors, headers and a few single-style ICs being the only exceptions. The cSBC employs an Intel 80C251 micro-controller as its processor. This processor provides 1K of on-board RAM and no on-board ROM. The controller is clocked at 16 MHz using a crystal.

cSBC Memory Space



Page 43 of 141

The cSBC is designed to support a JEDEC-standard, non-volatile FLASH memory device up to 512K x 8 bits in size for code and fixed data. The board supports either 128K or 512K SRAM memory device as needed for program volatile memory. Complete address decoding is provided via the MAX PLD, the CBSC bus master, allowing the address space to be arbitrary and changed via the PLD code. The 80251 can address four 64K segments, referred to as 0x00, 0x01, 0xFE and 0xFF as per Intel literature. The firmware has the ability to map any FLASH or SRAM segment to any CPU segment via SFR’s in the MAX PLD.

FLASH RAM


At startup the CPU executes the boots code which programs the FLEX PLD and then maps in either NT or Prodigy runtime firmware as appropriate based on the most significant bit of the CCA REV register. To switch from boot code to run code the firmware jumps to SRAM and executes a code snippet which pages the boot code out of 0xFF and the desired firmware into 0xFF. The snippet then jumps from SRAM back to 0xFF to execute the firmware. The cSBC contains a single 128K x 8 bit SRAM which provides read/write memory. The SRAM's segments are arbitrarily mapped to any CPU segment by the CPU mapping registers.

cSBC Functions The microprocessor-based Single Board Controller (cSBC) provides overall operation and control of the scan table.

FLEX PLD Peripherals The majority of scanner related programmable logic functionality is contained in the FLEX PLD, an Altera EPF6024AQC208-3 device. On each cold boot the CPU reprograms the FLEX devices from an image stored in it's FLASH. As such a firmware download of a new FLEX image is required to permanently upgrade the PLD code. The functional components of the programmable logic are discussed in the following subsections. Polarity of operation can be inferred from bit names and use of preceding slash for inverted logic bits.

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Note that ports A-F are reloaded with default values at time of CPU reset and remain in the default state until SCANNER_RESET has been cleared and new values are written by the firmware. Defaults for port F and all other registers are invoked at power up only.

PORT A


Bit

Name

R/ W

Def.

Description

0

trans_enable

R/W

0

Transverse motor enable – low blocks trans motor pulses and forces Centent drive to standby current level.

1

/trans_fwd

R/W

0

Transverse motor direction control.

2

/shutter_open_ctrl

R/W

1

Shutter solenoid control.

3

trans_lsw_override

R/W

0

Transverse limit switch override – prevent limit switch contact from blocking step pulses at hardware level.

4

long_enable

R/W

0

Longitudinal motor enable – low blocks trans motor pulses and forces Centent drive to standby current level.

5

/long_fwd

R/W

0

Longitudinal motor direction control.

6

long_lsw_override

R/W

0

Longitudinal limit switch override – prevent limit switch contact from blocking step pulses at hardware l evel

7

/collimator_open_ctrl

R/W

1

Collimator solenoid control.



Page 45 of 141

PORT B


Bit

Name

R/W

Def.

Description

0

/trans_front_lsw

R

N/A

Transverse front limit switch position.

1

/trans_back_lsw

R

N/A

Transverse back limit switch position.

2

/long_foot_lsw

R

N/A

Longitudinal foot limit switch position.

3

/long_head_lsw

R

N/A

Longitudinal head limit switch position.

4

trans_count_eq[0]

R

N/A

Set when transverse step counter equals zero.

5

long_count_eq[0]

R

N/A

Set when longitudinal step counter equals zero.

6

/shutter_open_sense

R

N/A

Shutter limit switch position.

7

/collimator_open_sense

R

N/A

Collimator limit switch position.

PORT C Bit

Name

R/W

Def.

Description

0

/long_rev_pos

R

N/A

Patient positioner (joystick) input.

1

/long_fwd_pos

R

N/A


2

/trans_rev_pos

R

N/A


3

/trans_fwd_pos

R

N/A


4

/hvps_ac_relay

R/W

1

Enable AC power to X-ray HVPS.

5

/motor_fail_enable

R/W

1

Arm logic to shutdown scanner if OMI/OMD inputs not sensed.

6

ags_enable

R/W

0

Enable detector automatic gain control feedback circuit.

7

/motor_power

R/W

1

Enable 24VDC to the stepper motor drives (a.k.a. Centents).

Page 46 of 141



PORT D Bit


Name

R/ W

Def.

Description

0

flex_max_i/o_[0]

R/W

0

Output signal to MAX PLD (diagnostic use only).

1

flex_max_i/o_[1]

R/W

0


2

flex_max_i/o_[2]

R/W

0


3

flex_max_i/o_[3]

R/W

0


4

flex_diag_3

R/W

0

Firmware controlled diagnostic LED.

5

pit_enable

R/W

0

Enable Programmable Interval Timer output pulses.

6

flex_diag_1

R/W

1


7

/laser_on

R/W

1

Patient locator laser control.

PORT E Bit

Name

R/ W

Def.

Description

0

low_range_dac

R/W

0

Switches mA DAC from 2.048V to 0.500V reference.

1

trans_motor_accel

R/W

0

Enables motor interrupt on every micro step.

2

low_range_adc

R/W

0

Switches ADC from 5.000V to 0.500V reference.

3

long_motor_accel

R/W

0

Enables motor interrupt on every micro step.

4

hvps_vendor_id

R

N/A

For 7681 supply, 0 = Spellman, 1 = Bertan.

5

iq_hvps

R

N/A

Set by resistor placement to indicate 0311/0312 supplies.

6

/hvps_enable_status

R

N/A

Enable status monitor from 7681 supply.

7

/power_up

R

N/A

Set to indicate cold boot.



Page 47 of 141

PORT F


Bit

Name

R/W

Def.

Description

0

/motion_fail_enable

R/W

1

Arm scanner shutdown if OMI/OMD pulses w/o step pulses.

1

long_motor_fail_axis

R/W

0

Motor fail circuitry axis control, clear for transverse.

2

/hvps_enable

R/W

1

Enable output to 7681 supply.

3

flex_diag_2

R/W

0


4

/arm_estop_sense

R

N/A

Emergency stop sense bit.

5

spare_jmp_[1]

R

N/A

Unused input, resistor or jumper selectable on CCA.

6

spare_jmp_[0]

R

N/A

Unused input, resistor or jumper selectable on CCA.

7

cpu_p1_2

R

N/A


PORT G Bit

Name

R/W

Def.

Description

0

adc_mux_[0]

R/W

0

ADC analog MUX input selection control bit.

1

adc_mux_[1]

R/W

0


2

adc_mux_[2]

R/W

0


3

adc_mux_[3]

R/W

0


4

adc_mux_enable

R/W

0

ADC MUX output enable control.

5

8ms_clock

R/W

0

Clock output provided to MAX PLD.

6

unused

N/A

N/A

For expansion.

7

unused

N/A

N/A

For expansion.

TRANS / LONG MOTOR Dual axis stepper motor control is provided entirely by the FLEX PLD. The drives provide 10 micro steps per full step. The firmware can track move status by reading the 16 bit READ register. As part of the setup for a move the host and/or firmware must enable the motors via the /motor_power, trans_enable, and long_enable outputs and setup the trans_lsw_override, long_lsw_override, /motion_fail_enable, / motor_fail_enable, and long_motor_fail_axis outputs as desired. If the system is in scanner reset for any reason the FLEX PLD will over-ride the / motor_power output and prevent 24V power from reaching the motor drives. Page 48 of 141



AGS ROLL This is a read only 8 bit register which returns the count of AGS roll-over events since the previous read of the register. The AGS roll counter is reset on read only.

AGS DAC This port provides R/W access to the AGS circuit's 8 bit U/D counter. The DAC's analog voltage is tied to the gain control input of the variable gain amplifier (VGA) used to control gain of the detector input signal. As such the firmware can read this counter to determine the current DAC voltage level and hence gain level. If ags_enable is low this port gives the firmware direct control of the AGS DAC as a parallel R/W device. If ags_enable is high, the firmware can write to the port but the DAC will continue to respond to UP/ DOWN requests from the AGS DCA circuitry and hence quickly return to the AGS current operating voltage. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

HE/LE COUNTERS These read only ports provide access to the 16 bit event counters which are incremented each time the DCA circuitry detects an input pulse within the HE or LE windows (as defined by the LEL, LEH, HEL, and HEH DAC settings). These counters are read in two 8 bit bus cycles, MSB then LSB. TPIT MSB/

SCANNER RESET The scanner reset register is used to provide failsafe shutdown operation of the scanner. A falling edge on any of the inputs to this register will latch the current value of the register and drop the /SCAN_FAIL_ANY output. The MAX PLD latches the master reset register and raises CPU_RESET in response to the falling edge on /SCAN_FAIL_ANY. The MAX PLD also provides SCANNER_RESET as the logical OR of CPU_RESET and!/ SCAN_FAIL_ANY. The FLEX PLD uses it's SCANNER_RESET input as the enable bit to the tri-state buffers used to drive all safety critical output lines including shutter control, HVPS relay control, motor relay control, etc. As such the scanner is locked into a fail-safe mode whenever CANNER_RESET is asserted. The MAX's master reset register will remain latched until the next rising edge on the HOST_RTS input. When the cSBC is latched into reset by a scanner error it will remain in CPU reset until the host drops the RTS line and reasserts it. It will remain in scanner reset until the CPU reads the scanner reset register following the next raising edge of the RTS line at which the condition causing the /SCAN_FAIL_ANY has been cleared. The firmware passes the value of the reset registers to the host to allowing the host to display appropriate error messages to the operator. The host will be unable to perform any scanner related operations until the SCANNER_RESET has been cleared. Red diagnostic LED's are provided for both scanner and CPU reset lines (D19 and D20). The CPU reset line is tied to the host CTS output such that the host sees a CTS event when the cSBC enters CPU reset. The DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 49 of 141

host code provides a CTS event handler which reads the reset registers and prompts the user accordingly. The firmware can also initiate a reset sequence in response to fatal error conditions by writing a 'death code' to the suicide reset register. Resets can also be initiated by the manual push button on the cSBC and by a low 5VDC power condition as sensed by the MAX705 supervisor. The scanner register is also latched at the end of read cycles such that current status can be ascertained by a double read. A bit map of the scanner reset register is provided below


Bit

Name

R/W

Def.

Description

0

/thermostat_open_sense

R

N/A

Tube head thermostat over temperature.

1

/external_estop_sense

R

N/A

Emergency stop input from external options block.

2

/dc_power_fail

R

N/A

Loss of one or more of +5VDC,+12VDC,12VDC, or +24VDC.

3

/long_motor_fail

R

N/A

Motor failure detected on longitudinal axis.

4

/trans_motor_fail

R

N/A

Motor failure detected on transverse axis.

5

/dmb_error

R

N/A

DMB dropped it’s CTS indicating a DMB reset event.

6

/motion_fail

R

N/A

OMI/OMD pulses detected without step pulse (manual arm motion).

7

/watchdog_reset

R

N/A

Watchdog time-out indicates firmware crash.

HVPS Errors The HVPS error register is used to monitor the status of the LUNAR p/n 7681 (NT (B) and MD+ only) X-ray Generator HVPS. If the register value is not equal to 0xF when /hvps_enable is low, the FLEX will raise the HVPS_ERROR_INT output to the MAX PLD. The MAX PLD latches this into the IIR register and issues an interrupt to the CPU. As such status of the Xray Generator is monitored when the unit is enabled. The handler for X-ray Generator interrupt reads this register to determine the cause of the interrupt. The X-ray Generator register is also latched at the end of read cycles such that current status can be ascertained by a double read. A bit map of the register is provided below. Bit

Name

R/W

Def.

Description

0

/hvps_error_0

R

N/A

Error code bit from 7681 supply.

1

/hvps_error_1

R

N/A


2

/hvps_error_2

R

N/A


3

hvps_enable_status

R

N/A

Set when /hvps_enable == /hvps_eanble_status

4

Unused

N/A

N/A

Expansion room.

Page 50 of 141



5

Unused

N/A

N/A

Expansion room.

6

Unused

N/A

N/A

Expansion room.

7

Unused

N/A

N/A

Expansion room.

DC FAIL The DC fail error register latches the status of the DC power monitors at the time of reset. If scanner reset code indicates /dc_power_fail the firmware can read this register to identify the specific DC source failure. The register is also latched at the end of read cycles such that current status can be ascertained by a double read.


Bit

Name

R/W

Def.

Description

0

/plus_scanner_fail

R

N/A

Loss of +24V power input.

1

/plus_analog_fail

R

N/A

Loss of +12V power input.

2

/minus_analog_fail

R

N/A

Loss of -12V power input.

3

Unused

N/A

N/A

Expansion room.

4

Unused

N/A

N/A

Expansion room.

5

Unused

N/A

N/A

Expansion room.

6

Unused

N/A

N/A

Expansion room.

7

Unused

N/A

N/A

Expansion room.

DCA / AGS / BIAS DAC's The cSBC uses a single 10 bit octal DAC, the Linear Technology LTC1660, to generate the AGS and DAC window reference voltages and the bias program voltage. KV/mA DAC The cSBC uses a single 12 bit dual DAC, the Linear Technology LTC1454, to generate the HVPS kV and mA program voltages.



Page 51 of 141

ARC/FIL DAC The cSBC uses a single 10 bit dual DAC, the Linear Technology LTC1661, to generate the HVPS filament limit and arc detect threshold voltages.

PEAK DAC The cSBC uses a 12 bit DAC, the Linear Technology LTC8043, to generate the detector peak gain voltage.

MAX PLD Peripherals The programmable logic section is based on an Altera MAX EPM7128STC100-15 device. The MAX device is FLASH based (non-volatile) and is programmed at the time of CCA assembly. The functional components of the programmable logic are discussed in the following subsections. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Interrupts The CPU's interrupt capacity is effectively increased by running several interrupt signals to a register in the MAX PLD and tying the register output to the CPU external INT 0 input. The firmware interrupt handler for INT 0 then reads this register to identify the source of the interrupt and handles it accordingly. The firmware then writes a bit masked '1' back to the IIR to clear the bit of the interrupt it has serviced (the R/C in the table stands for READ/ CLEAR).

Bit

Name

R/ W

Def.

Description

0

HOST_UART_INT

R/C

N/A

Host UART interrupt.

1

DEBUG_UART_INT

R/C

N/A

Debug UART interrupt.

2

DMB_UART_INT

R/C

N/A

DMB UART interrupt.

3

HVPS_ERROR_INT

R/C

N/A

HVPS error interrupt.

4

8mS_CLOCK

R/C

N/A

8ms clock tick interrupt from FLEX PLD.

5

POWER_FAIL_INT

R/C

N/A

Power down pending in 5ms interrupt from DC supply.

6

Unused

N/A

N/A

Expansion room.

7

Unused

N/A

N/A

Expansion room.

Page 52 of 141



MASTER RESET The master reset register will force a CPU and scanner reset condition on the falling edge of any of its listed inputs. The contents of the register will be latched at the time of reset such that when the CPU next comes out of reset the firmware can read the register to determine what caused the preceding reset and report the appropriate code to the host. If the reset was cause by the CPU_RST_WR input, the suicide reset register contains the specific error code. If the reset was cause by the /SCAN_FAIL_ANY input, the scanner reset register contains the specific error code. The CPU and scanner resets will remain latched until the next rising edge of the RTS input. At this time the CPU reset will be cleared if /POWER_RESET bit is not asserted and the scanner reset will be cleared if /SCAN_FAIL_ANY is high. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Bit

Name

R/ W

Def.

Description

0

/POWER_RESET

R

N/A

MAX705 supervisor detects VCC < 4.65V.

1

/HOST_RTS

R

N/A

RTS reset request from host via comm line.

2

/MANUAL_RESET

R

N/A

Push button pressed.

3

Unused

R

N/A

Expansion room, reads as ‘1’.

4

Unused

R

N/A


5

Unused

R

N/A


6

CPU_RST_WR

R

N/A

Write to the suicide register, read suicide reg for error code.

7

/SCAN_FAIL_ANY

R

N/A

Scanner reset register latched, read scanner reg f or error code.

SUICIDE RESET The CPU Reset SFR is a byte register into which the CPU can write a failure code. In response to the write the MAX PLD will store the failure code and assert the CPU_RESET line. The CPU_RESET line will be released on the next rising edge of the host RTS, at which time the CPU will be able to read the bit code from this SFR to determine the cause of the previous reset.

MISC OUT The misc. output register is used to control the misc. output functions listed in the following table.

Bit

Name

R/ W

Def.

Description

0

Unused

N/A

N/A

Expansion room.

0


DPX-NT/MD+ ServiceDIAG_2 Manual (Rev. 3 - 2010) 1 MAX R/W


Page 53 of 141

2

DMB HWPT

R/W

0

Enable direct connect of host and DMB XCVR’s, bypassing UART’s, for maximized scan data bandwidth DMB to host.

3

RESET OVERRIDE

R/W

1

Enable override of CPU_RESET signal. Set to 1 on power-up such that firmware can load the FLEX PLD at power-up regardless of the host RTS state.

4

Unused

N/A

N/A

Expansion room.

5

Unused

N/A

N/A

Expansion room.

6

Unused

N/A

N/A

Expansion room.

7

Unused

N/A

N/A

Expansion room.

MISC IN . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The misc. output register is used to control the misc. input functions listed in the following table Bit

Name

R/ W

Def.

Description

0

BOOT JUMPER

R

N/A

JP4, placed to force firmware to remain in boot code.

1

CPU_P1_2

R

N/A

Input from CPU port 1, pin 2 (diagnostic use only).

2

Unused

N/A

N/A

Expansion room.

3

Unused

N/A

N/A

Expansion room.

4

Unused

N/A

N/A

Expansion room.

5

Unused

N/A

N/A

Expansion room.

6

Unused

N/A

N/A

Expansion room.

7

Unused

N/A

N/A

Expansion room.

Page 54 of 141



2.4.1 Motion Control Stepper Motor Control The stepper motors use the same interface design as used on previous LUNAR products DPX-IQ and Prodigy. The solid state relay has been replaced with a FET switch to save cost and board space. Diodes are placed in series on the Centent power lines to prevent back EMF generated when the arm is moved manually from reaching the 24V planes and damaging the cSBC.

OMI/OMD Input


The optical motion interrupt (OMI/OMD) sub-system connects to the transverse and longitudinal OMI/OMD CCA's. The OMI/OMD CCA's are located on the far end (the gear end farthest from the motor) of each drive axis. When the axis is in motion a small toothed wheel spins through the OMI/OMD opto's beam and pulses are sensed back on the cSBC. In this manner the system can sense a drive circuit, motor, or belt failure which might otherwise result is a concentrated exposure point during a patient scan. As on Prodigy, logic in the FLEX PLD is used to qualify the CH A and CH B inputs into a single 'valid motion' output. Based on the phases of the square wave inputs on CH's A&B, the FLEX is able to sense a change in direction. The circuit provides hysteresis to reject false motion inputs resulting from scanner vibration when a wheel edge stops in the center of the opto beam at the end of a move. OMD Replaces OMI As of mid-2007, the OMI (Optical Motion Interrupt) Board (LNR7366) is end of life. The OMD (Optical Motion Detection) Board is its replacement and is available in a Service kit (LNR42824). The OMI board is NOT compatible with these systems listed and going forward. LNR42824 OMD Service Kit will be required if an OMD needs to be replaced (Figure 1). First System ID #containing OMD board for each product line: Prodigy Advance (P8) Full PA+/-301022 Prodigy Advance (P8) Compact PA-310210 Prodigy Pro (P8) Full DF+/-301027 Prodigy Pro (P8) Compact DF-310212 DPX-NT (NTE) Full NT+/-150581 DPX-Bravo BT-21214 DPX-Duo DT-30377 Note: The OMI for DPX-IQ motion detection and Prodigy, DPX-NT, DPXBravo and DPX-Duo shutter open/close detection (LNR2817) is NOT end of life.



Page 55 of 141


Figure 1 Brackets included in OMD Service Retrofit Kit (LNR42824). Note: 42812, 42822 and 42823 are only available in the LNR42824 kit.

Page 56 of 141



2.4.2 Patient Positioners Four optically isolated inputs are provided for patient positioning. These are used by the firmware to implement a joystick mode which is used in conjunction with the laser to position the X-ray beam as desired over the patient immediately prior to a scan.

Limit Switches Four optically isolated inputs are provided for limit switches. These are used by the firmware to define the transverse and longitudinal table limits.

2.4.3 X-ray Source Control Mechanical Interlocks . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The cSBC is designed such that a high on the scanner reset net disables all scanner functionality and assures a know, fail safe, state. All scanner control outputs are driven by the FLEX PLD. T. A scanner reset will force all these FLEX scanner outputs to a high impedance state, de-energizing the opto's and disabling the scanner. The FLEX device is SRAM based and hence must be reprogrammed by the CPU at power up. When the device is not programmed all I/O pins default to the high impedance state. As such the scanner will also be in a fail safe state when the FLEX is not programmed. The cSBC provide a failsafe mechanism independent of the programmable logic via the +5V_IO circuit. If one or more of either the E-stop, external Estop, or tube housing assembly thermostat is open, the FET driving the +5V_IO net from the +5VDC plane will be disabled. The +5V_IO net provides power to the emitter anode of all opto's which drive critical scanner functions. As such the scanner will enter a failsafe state in response to these mechanical interlocks, even in the event of a PLD device failure. The +5V_IO FET will also be disabled by either a HOST_RTS or CPU_RESET.

2.4.4 Shutter / Collimator Drive The shutter and collimator solenoid drive circuits are the same as that used on Prodigy. The first FET is used for an initial 'hard hit' on open commands. It presents 24V directly to the solenoid for several hundred msec's, resulting in a large initial current pulse to the solenoid. The second FET provides the 'hold' current through a pair of current limiting power resistors. The hold FET is tied directly to the /shutter_open_ctrl bit.

2.4.5 End of Exposure Alarm An on-board end of exposure alarm is provided. The alarm chosen is the board mount equivalent of that used on IQ and Prodigy.

2.4.6 Panel LED's DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 57 of 141

The 4 panel LED's, power on, X-ray on, source exposed, and laser on, are all driven PS2501-2 opto's through 750R0 / 1W current limiting resistors.

2.4.7 HVPS Control A single, 16 channel multiplexed, 16 bit, high accuracy, ADC is used in conjunction with several lower cost, lower bit resolution DAC's. Serial DAC's and ADC's are chosen to conserve board space and simplify routing. Serial parts are typically also lower cost as their maximum bandwidth is limited by the serial baud rate.


A jumper and/or DNP'd resistor pad is provide to drive the IQ_HVPS line, which the firmware reads to determine which HVPS it is intended to operate. The PWB provides lemo style connector pads for use with the traditional 0311/0312 (DPX-NT (A)) X-ray Generator and D-MAX CCA. For the 7681 (DPX-NT (B) and MD+) the lemos are DNP'd and a single DB-25 connector is used to control the X-ray Generator. An opto bank is also provided to support the digital interface to the 7681 x-ray generator.

2.4.8 ADC A single LTC1454 12 bit, serial, dual channel, DAC is used to provide the kV and mA program voltages. The DAC is used in the x2 configuration such that the full scale output is twice the reference voltage. Voltage outputs feed back to the ADC MUX such that firmware can calibrate out DAC INL errors. A single LTC1661 10 bit, serial, dual channel, DAC is used to provide the arc threshold and filament current limit input voltages to the 7681 x-ray generator (DPX-NT (B) and MD+).

Page 58 of 141



2.4.9 mA Low Range To support the 50uA scan mode required by NT's thinner Cerium filter, an mA low range circuit is provided. The FLEX PLD provides a control bit by which the firmware can switch the mA DAC reference voltage from 2.048V to 0.5V, hence decreasing the LSB size, hence allowing the firmware to take smaller voltage steps when ramping to low uA settings. A second control bit is provided to switch the ADC from 5.0 to 0.5V reference.

2.4.10 Detector Interface The cSBC provides a single channel of detector electronics including analog gain control, comparator circuitry and DCA/AGS logic within the FLEX PLD.


The cSBC is deigned to work with a traditional DPX IQ AMP 1890 CCA. The bipolar input from the AMP is received via a lemo connector and sees a 50 Ohm line termination. The Linear Tech LT1228 variable gain amplifier is used to provide peak and AGS gain control.

Gain Control DAC's The gain control stage uses cascaded AGS and peak DAC's to generate the gain control voltage to the LT1228.

2.4.11 Comparators and Reference DAC's The cSBC uses the same CMP401 high speed comparators to convert the analog bipolar signal to multiple digital threshold outputs. Comparator reference voltages are generated by a single LTC1660 10 bit, serial, octal DAC.

2.4.12 Bias Control The 7th channel of the DCA octal DAC is used to generate the program voltage for the PMT bias supply. The 0-3V output it mapped to 0-9V and driven by the OPA2131 op-amp to the bias supply control cable. Bias program voltage from the DAC and bias monitor voltage from the supply are both fed to the ADC MUX such that the firmware has full control over the PMT bias supply.

2.4.13 Communications Ports Host RS-232 The host I/O port provides optical isolation per medical leakage requirements of EN 60601-1-1, Annex BBB, section 7. QT's 6N136 opto's are used to provide the required 115.2KB operational bandwidth and the required 2500 Vrms standoff. A DB-9 female connector is provided on the host side of the isolation barrier. RS-232 is supported by populating the XCVR U26. R. All NT / MD+ scanners run at 19.2KB. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 59 of 141

Debug RS-232 Port The debug port is provided such that the firmware can echo status messages and other information to a dumb terminal to support debugging, development, testing, and servicing.

2.4.14 Diagnostic LED's 16 diagnostic LED's are provided by the cSBC. Functionality is listed below


LED

Color

Function

Description (status indicated when lit)

D13

Green

+24V

+24V DC input from supply present.

D14

Green

+12V


D15

Green

-12V

-12V DC input from supply present.

D7

Green

+5V


D16

Red

FLEX CONFIG

FLEX PLD not programmed.

D20

Red

CPU RESET

CPU in reset mode.

D19

Red

SCANNER RESET

Scanner in reset (failsafe) mode.

D27

Red

AGS ROLL

AGS roll over or under detected.

D29

Amber

FLEX DIAG 1

Diagnostic LED for misc use by firmware, control reg in FLEX.

D31

Amber

FLEX DIAG 2

Diagnostic LED for misc use by firmware, control reg in FLEX.

D22

Amber

MAX DIAG 2

Diagnostic LED for misc use by firmware, control reg in MAX.

D28

Amber

TRANS OMI

Valid transverse motion sensed by OMI/OMD circuitry.

D22

Amber

LONG OMI

Valid longitudinal motion sensed by OMI/OMD circuitry.

D25

Amber

HE COUNT

Valid high energy photon event sensed by DCA circuitry.

D23

Amber

LE COUNT

Valid low energy photon event sensed by DCA circuitry.

D21

Amber

HVPS ENABLE

7681(NT (B) and MD+ ONLY) HVPS enabled.

2.4.15 Laser Control The laser control circuit uses a PS2501-2 opto to control a FET which in turn drives +5V_ANA to the patient locator laser.

Page 60 of 141



2.4.16 Power Distribution The DPX NT system reduces scanner cost by using a single switching DC power supply which provides +5,+/-12, and +24VDC. The supply is connected directly to the cSBC via J14. J13 is provided as a power out

connector to the D-MAX CCA for NT-A. The PWB is divided into 4 ground plane regions - DGND for +5V digital returns, AGND for +/-12V analog returns, SCNGND for +24V returns, and ISO_GND for the host I/O island. The 24V plane contains primarily power FET switches and power resistors used to control scanner motors, X-ray source, LED, etc. The +/-12V planes contain analog electronics used for detector and HVPS control. A +12V regulator is used to produce 12VDC for the Centent drives of off +24VDC, maintaining isolation from the +12V plane. An additional +5V regulator is used to make 5V for the OMI/OMD’s of off +12V motors. 4 opto channels are used to sense the presence of the 4 DC input voltages. The opto outputs are used to drive 4 green power on indicator LED's (D7, D13, D14, D15) and to allow the CPU to detect power outs. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

2.5 X-ray Source The Tube Head consists of an oil-filled metal housing which contains a fixedanode Xray Insert (essentially a vacuum tube housing assembly diode), leadtype shielding, collimating devices, a filament transformer, electrical connectors, and a Cerium (Kedge) filter. The X-ray tube housing assembly gets its input from the high voltage power supply(s) which provide a constant potential of up to 5 mA at 76kV and operate at a high frequency of 50 kHz. This produces a stream of electrons in the cathode and accelerates them towards the anode thus producing X-rays as well as heat.

2.5.1 X-ray generation and Spectrum 



 



The X-ray Insert converts current into x-rays by accelerating the electrons across a large potential from the cathode into a tungsten target on the anode. The x-rays produced by the x-ray insert are filtered by the cerium filter to produce a dual energy spectrum. The x-ray spectrum has peaks at 70 and 38 kV. Insert potential is provided by the High Voltage Power Supplies (see section 2.6) The tube housing assembly current is set by the cSBC at 0.1 mA or 1.50 mA (DPX-NT) 0.1mA or 0.750 mA for DPX-MD+ depending on the acquisition type. Tube Current is set by the cSBC and regulated by the D-MAX Board (DPX-NT (A) NT (B) and MD+ units use the model 7861 X-ray generator which includes all tube current regulation functions (see section 2.7).



Page 61 of 141

2.6 Display Panel • The Display Panel of the DPX-NT / MD+, located on the front face of the upper arm, is the main operator interface outside the host computer.


Figure 2-13. DPX-NT / MD+ display panel

• Rocker switches on the panel allow operator control of the beam position. • Four indicators display system status. • A green Light Emitting Diode (LED) indicates a power-on condition; it lights when the +26VDC power supply comes on. Power on LED is lit whenever scan table power i s on.

• A yellow LED indicates if the laser is on • An amber X-ray On LED indicates that x-rays are being produced (current is flowing through the X-ray Insert), though exposure is not necessarily taking place. The X-ray on LED is lit when current is flowing through the Xray insert.

• The yellow Shutter Open LED comes on is the Shutter open and exposure possible. The Shutter open LED is controlled by the cSBC, the cSBC will allow the shutter to open even if the lamp is not lit (shutter open indicator is also on the PC controller screen). Note:

It is not recommended that scanner operation be continued if These LED's signal the operator of exposure to x-rays and must be replaced as soon as possible.

Page 62 of 141



2.7 High Voltage Power Supplies The DPX-NT / MD+ X-ray production system combines a constant potential generator (consisting of one (DPX-NT(B) and MD+) or two (DPX-NT (A)) high voltage power supplies) and an X-ray tube housing assembly. The high voltage power supply(s) (HVPS), operating at a high frequency of 50 kHz, provide a continuous output of 38 kV each and up to 5 mA to the X-ray tube housing assembly. The anode is composed of a tungsten alloy. The specifications of the X-ray generation subsystems are outlined in section 2.x. • The High Voltage Power Supply(s) provide the anode/cathode potential to the X-ray insert.


• DPX-NT (A) scanners use two high-voltage power supplies (±40kVDC). During normal operation, 76kVp is applied (+38kV at the anode and 38kV at the cathode). • DPX-NT (B) and MD+ scanners use a single high-voltage power supply (40kVDC) During normal operation, 76kVp is applied to (+38kV at the anode and -38kV at the cathode), • The High Voltage Power Supply(s) are controlled by the cSBC (see section 2.4). • The power supply(s) are powered by the AC line voltage and have their own built in fusing. • The AC power is routed thru and the supplies are enabled by a solid state relay(s) which is mounted on the electronics pan (see section 2.1.1).

2.8 D-MAX Board (DPX-NT (A) ONLY) 2.8.1 D-MAX Board Function • The Tube Head and D-MAX Board work with the DC power supply to supply tube housing assembly head current. • The current is set by the cSBC. • D-MAX board actually regulates current to the filament transformer in the Tube Head. • When errors are detected by the cSBC, (for example, loss of arm motion) the relay will switch off and prevent production of x-rays.

2.9 XORB Board (DPX-NT (A) ONLY)



Page 63 of 141

The XORB printed circuit board provides protection to various circuits (low voltage) from transients within the HVPS and tube housing assembly head (see 2.1.1 for location). • There may be occasional static discharges within the Tube Head. The transients caused by these static discharges (arcs) are shunted to ground through the array of transorbs present on the XORB board. • There is no safety hazard to personnel, however, the electronics could be damaged were no protection provided.

2.10 Detector Sub System 2.10.1 Detector Overview . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• The detector has a Sodium Iodide (NaI) crystal that serves as a scintilator • The light emitted by the scintilator is passed to the Photo Multiplier Tube (PMT) which amplifies the signal • The detector has its own dedicated High Voltage Power Supply, used for supplying detector (PMT) bias. • The detector bias is controlled by the cSBC, it is adjusted in the peak setting test during the daily QA.

2.11 X-Ray Collimator Subsystem • The Shutter is actuated by a solenoid using +24 VDC, the voltage is reduced to a holding voltage of 12VDC after the shutter is opened. • This solenoid is controlled by signals generated on the cSBC. • A limit switch determines the shutter position and reports it to the cSBC. • This assembly is located on top of the X-ray Tube Head.

Page 64 of 141



2.12 DPX-NT / MD+ Specifications 2.12.1 Component specifications Table

3-2 gives specifications for standard components shipped with the DPX-NT / MD+ system. Table 2-2. Component specifications.

Component


Specifications

Dimensions: 197.5 cm x 62.3 cm x 132.5 cm Scanner table* Weight aprox 272kg Maximum patient weight supported: 136kg Console table 78.5 cm x 63.3 cm x 48.1 cm Greater than 266 Mhz Pentium 64MB Greater than 1GB hard disk 17” SVGA monitor (800x600x16-bit color) # Computer LS-120 Super Drive CD ROM NT operating system (with Service Pack 6.0 and Internet Explorer 4.01 or greater with service pack 2.0) HP DeskJet 930C Printer 44.7 cm x 35.6 cm x 19.1 cm *Width is measured from the front edge of the scanner table to the back edge of the scanner arm. Height is measured from the top of the scanner arm to the bottom of the scanner arm.

#Some languages may require 1024x768x16-bit color to fit the translated software text on the screen

2.12.2 Functional specifications General specifications Focal spot to image receptor distance is 67 cm. Attenuation equivalence of patient support table is 0.7 mm Al.

2.12.3 Maximum scan area (long x transverse) •

AP Spine Measurements 40.9 cm x 22cm

• Femur Measurements 20.9 cm x 17.9cm • Total Body Measurements 195 cm x 60 cm measurement field DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 65 of 141

Forearm Measurements (for Investigational use only) 40.9 cm x 10 cm measurement field Lateral Measurements (for Investigational use only) 40.9 cm x 10 cm measurement field

2.12.4 Programs Note:

Depending on the number of options purchased, not all of the options listed below may be included with the DPX-NT / MD+ system software:

• AP spine measurement and analysis • Femur measurement and analysis . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• Total Body measurement and analysis • Forearm Measurement and analysis • Lateral Spine measurement and analysis • Quality Assurance

2.12.5 Environmental specifications Operational environment Adhere to the specifications that follow during scanner operation: • •Ambient Space (Interior Subcomponents)–For scanner operation and servicing, do not block the area around the scanner table. Make sure there is a minimum clearance of 30.5 cm at the head and foot ends of the scanner table, at least 15.2 cm for the arm side, and 45.7 cm for the operator side. • Ambient Space (Ventilation)–Do not block the cooling vents on the computer and scanner table. Make sure there is 15.2 cm from the console table to the wall for cable clearance and computer plugs. • Dust, Fumes and Debris–Install the system in a clean, ventilated area. Dust and other airborne debris can cause the diskette drive heads and other sensitive mechanical components to malfunction. LUNAR recommends that smoking is not permitted in the scanner room. • Humidity–Make sure the humidity for the scanner area is 20%–80%, non-condensing. • Static Electricity–Install and operate the system in a static-free area. Adhere to minimum humidity requirements to prevent malfunctions caused by static electricity. Page 66 of 141



• Shock and Vibration–Make sure the scanner table does not receive shock greater than 1 G for more than 1 millisecond. Make sure the scanner table does not receive vibrations greater than 0.25 G at 5 Hz. • Temperature– Make sure the temperature during system operation is 65°F–81°F (18°C–27°C). Note:

When the system is turned off, or there is a power failure, allow the system to be on and let it warm for one hour. After one hour, complete a Quality Assurance procedure.

2.12.6 Storage and transport environment Adhere to the specifications that follow for scanner storage and transportation: . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• Humidity, 0% to 95% non-condensing. • Atmospheric pressure, 500 to 1060 hPa. • Temperature, -40° to 70° C.

2.12.7 X-ray generator specifications X-ray generator Table 2-3 contains information about the x-ray generator for DPX-NT (B) and MD+ series devices and the standard referenced. Table 2-4 contains information DPX-NT (A) systems. Table 2-3. LUNAR 7681 X-ray generator technical information (system no. 72000 and higher)

Classification

Class I Equipment

IEC 601-2-7 5.1

Degree of protection against electrical shock

Type B equipment

IEC 601-2-7 5.2

Protection against ingress of liquids

Ordinary medical electrical equipment

IEC 601-2-7 5.3

Connection to supply mains

Power supply cord

IEC 601-2-7 6.1g)

Mode of operation

Continuous

IEC 601-2-7 6.1m)

Maximum X-ray tube voltage

76 kV

IEC 601-2-7 6.1m)

Maximum X-ray tube current

3 mA

IEC 601-2-7 6.1m)

Rated mains voltage

100-240 VAC

IEC 601-2-7 6.1j)1

Number of phases in mains

1

IEC 601-2-7 6.1j)2

Mains frequency

50/60 Hertz

IEC 601-2-7 6.1j)3

Required over-current releases

15 Amp dedicated service

IEC 601-2-7 6.1j)5



Page 67 of 141


Heat dissipative components

X-ray tube dissipates 243W max. into surrounding air through forced air convection. Flow rate: 36 m3/h (approx.) Temp. rise of air stream 25° C (approx.)

IEC 601-2-7 6.1t)

Allowable high voltage supplies

Spellman SBD40PN280X2890 or Bertan 2907.

IEC 601-2-7 6.8.1 and 50.2.101-102

Allowable tube head assemblies

LUNAR model 8548 or equivalent

IEC 601-2-7 6.8.1 and 50.2.101-102

Original language of accompanying documents

English

IEC 601-2-7 6.8.1

Maximum continuous kV, mA at nominal rated kV

76 kV, 3 mA

IEC 601-2-7 6.8.2 1)

Maximum intermittent kV, mA at nominal rated kV

76 kV, 3 mA

IEC 601-2-7 6.8.2 1)

Maximum continuous kV, mA at maximum mA

76 kV, 3 mA

IEC 601-2-7 6.8.2 2)

Maximum intermittent kV, mA at maximum mA

76 kV, 3 mA

IEC 601-2-7 6.8.2 2)

Continuous kV, mA for maximum electric output power

76 kV, 3 mA

IEC 601-2-7 6.8.2 3)

Intermittent kV, mA for maximum electric output power

76 kV, 3 mA

IEC 601-2-7 6.8.2 3)

Nominal electric power

0.243 kW

IEC 601-2-7 6.8.2 4)

Lowest current time product

0.20 mAs. Parameters: 76 kV, 0.10 mA, 2 seconds.

IEC 601-2-7 6.8.2 5)

Nominal shortest irradiation times

2 seconds.

IEC 601-2-7 6.8.2 6)

Method of x-ray tube voltage measurement

Voltage divider in high voltage power supply.

IEC 601-2-7 50.106.1

Method of x-ray tube current measurement

Shunt resistor in high voltage supply return line.

IEC 601-2-7 50.106.2

X-ray tube assembly reference axis

Line normal to the tube port, centered on tube port as shown in Figure 4.

IEC 601-2-7 6.1j)5) 50.107.1

Page 68 of 141



Reference loading conditions

8.21 x 105 Joules, 3 mA, 76 kV for 1 hour.

IEC 601-1-3 29.204.2

Focal spot to Image Receptor distance

57 cm

IEC 601-1-3 29.203.2

Attenuation equivalence of patient support table.

0.7 mm Al

IEC 601-1-3 29.206.2

Table 2-4. LUNAR 0311 / 0312 or 8531 / 8532 X-ray generator technical information (NT (A) Systems numbered 71999 and lower).

Classification Degree of protection against electrical shock . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Protection against ingress of liquids Connection to supply mains Mode of operation Maximum X-ray tube housing assembly voltage Maximum X-ray tube housing assembly current Rated mains voltage Number of phases in mains Mains frequency Required over-current releases

Heat dissipative components

Allowable high voltage supplies Allowable tube housing assembly head assemblies Original language of accompanying documents Maximum continuous kV, mA at nominal rated kV Maximum intermittent kV, mA at maximum kV DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Class I Equipment

IEC 601-2-7 5.1

Type B equipment

IEC 601-2-7 5.2

Ordinary medical electrical equipment Power supply cord Continuous

IEC 601-2-7 6.1g) IEC 601-2-7 6.1m)

76 kV

IEC 601-2-7 6.1m)

5 mA

IEC 601-2-7 6.1m)

100, 115, 230, 240 volts 1 50/60 Hertz 20 Amp dedicated service X-ray tube housing assembly dissipates 305W max. into surrounding air through forced air convection. Flow rate: 36 m3/h (approx.) Temp. rise of air stream 25º C (approx.) Spellman X2112/X2113/ rev. K and higher. Bertan 2411P and 2411N rev. A and higher. LUNAR p/n 0311 and 0312.

IEC 601-2-7 6.1j)1 IEC 601-2-7 6.1j)2 IEC 601-2-7 6.1j)3 IEC 601-2-7 6.1j)5

IEC 601-2-7 5.3

IEC 601-2-7 6.1t)

IEC 601-2-7 6.8.1 and 50.2.101-102

LUNAR model 8297or equivalent

IEC 601-2-7 6.8.1 and 50.2.101-102

English

IEC 601-2-7 6.8.1

76 kV, 4 mA

IEC 601-2-7 6.8.2 1)

76 kV, 5 mA

IEC 601-2-7 6.8.2 1) Page 69 of 141

Table 2-4. LUNAR 0311 / 0312 or 8531 / 8532 X-ray generator technical information (NT (A) Systems numbered 71999 and lower). (continued)

Maximum continuous kV, mA at maximum mA Maximum intermittent kV, mA at maximum mA Continuous kV, mA for maximum electric output power Intermittent kV, mA for maximum electric output power Nominal electric power


61 kV, 5 mA

IEC 601-2-7 6.8.2 2)

76 kV, 5 mA

IEC 601-2-7 6.8.2 2)

76 kV, 4 mA

IEC 601-2-7 6.8.2 3)

76 kV, 5 mA

IEC 601-2-7 6.8.2 3)

0.4 kW IEC 601-2-7 6.8.2 4) 7.89 mAs. Parameters: 76 kV, 2.63 Reference current time product mA, IEC 601-2-7 6.8.2 5) 3 seconds. Nominal shortest irradiation times 3 seconds. IEC 601-2-7 6.8.2 8) No specific wait period was imposed. IEC 601-2-7 Repetition rate for loading during tests Time between tests was approxi50.104.4 mately 20 seconds.

Method of x-ray tube housing assembly voltage Voltage divider in high voltage power IEC 601-2-7 measurement supply. 50.106.1 Method of x-ray tube housing assembly current Shunt resistor in high voltage supply IEC 601-2-7 measurement return line. 50.106.2 Line normal to the tube housing IEC 601-2-7 6.1j)5) X-ray tube housing assembly reference axis assembly port, centered on tube housing 50.107.1 assembly port as shown in figure 3-14. Reference loading conditions 1.09 x 106 Joules, 4 mA, 76 kV for 1 hour.IEC 601-1-3 Leakage radiation was measured at the 3mA, 76 kV IEC 601-1-3 following loading factors. Focal spot to Image Receptor distance 57 cm IEC 601-1-3 Attenuation equivalence of patient support 0.7 mm Al IEC 601-1-3 table.

Page 70 of 141




Figure 2-14. Reference axis and target angles for tube housing assembly head assembly

2.12.8 LUNAR 8548 and 8297 X-ray tube housing assemblies • Beam filtration is permanently fixed with a minimum 3.0 mm Aluminumequivalent. Refer to table 2-5 for model 8538 x-ray tube assembly or table 2-6 for model 8297 x-ray tube assembly. Note:

Beam quality has a minimum first half-value layer of 4.7 mm of Al at 76 kV



Page 71 of 141


Figure 2-15. Anode heating/cooling curves Table 2-5. LUNAR 8022 X-ray tube technical information.

Nominal anode input power

361 Watts

IEC 613/1989

Maximum anode heat content

6000 Joules

IEC 613/1989

Anode heating and cooling curves

Refer to figure 5.

IEC 613/1989

Anode target material

Tungsten

IEC 601-2-28

Reference axis

Refer to figure 4.

IEC 601-2-28

Target angle

78° (reference to normal)

IEC 601-2-28

Nominal focal spot values

0.5

IEC 336/1982

Maximum useful voltage

95 kVp

Not Applicable

Maximum filament current

2.2 Amperes

Not Applicable

Table 2-6. LUNAR 8548 x-ray tube head assembly (DPX-NT (B) and MD+ systems numbered 72000 and higher) technical information.

Inherent filtration

>3.0 mm Al/70 kV

IEC 522/ 1976

Filament characteristics

Refer to Figure 6.

IEC 613/ 1989

Nominal x-ray tube voltage Page 72 of 141


76 kV - Anode to Cathode IEC 613/ 38 kV - Anode to Earth 1989 38 kV - Cathode to Earth Service Manual (Rev. 3 - 2010) DPX-NT/MD+


Single load rating

228 W (3 mA, 76 kV) for up to 15 min.

IEC 613/ 1989

Serial load rating

228 W (3 mA, 76 kV) for up to 15 min. with a 5 min. cool down time between measurements.

IEC 613/ 1989

Maximum x-ray tube assembly heat content

260 kJoules

IEC 613/ 1989

X-ray tube assembly heating and cooling curves

Refer to Figure 7.

IEC 613/ 1989

Maximum continuous heat dissipation

243 Watts (3mA x 76kV + 15W filament)

IEC 613/ 1989

Maximum symmetrical radiation field

Diameter = 10 mm

IEC 806/ 1984

Dimensions

17 cm x 19.4 cm x 11 cm

IEC 601-228

Weight

8.6 kg

IEC 601-228

Table 2-7. LUNAR 8297 x-ray tube housing assembly (DPX-NT (A) systems 71999 and lower) technical information.

Inherent filtration

>3.0 mm Al/70 kV

IEC 522/ 1976

Filament characteristics

Refer to Figure 6.

IEC 613/ 1989

Nominal x-ray tube voltage

76 kV - Anode to Cathode 38 kV - Anode to Earth 38 kV - Cathode to Earth

IEC 613/ 1989

Single load rating

361 W (4.75 mA, 76 kV) for up to 4 min., 59 sec.

IEC 613/ 1989

Serial load rating

361 W (4.75 mA, 76 kV) for up to 4 min., 59 sec. with a 10 min. cool down time between measurements.

IEC 613/ 1989

Maximum x-ray tube assembly heat content

260 kJoules

IEC 613/ 1989

X-ray tube assembly heating and cooling curves

Refer to Figure 7.

IEC 613/ 1989



Page 73 of 141


Maximum continuous heat dissipation

361 Watts

IEC 613/ 1989

Maximum symmetrical radiation field

Diameter = 10 mm

IEC 806/ 1984

Dimensions

17 cm x 19.4 cm x 11 cm

IEC 601-228

Weight

8.6 kg

IEC 601-228

Figure 2-16. Cathode emission characteristics

Figure 2-17. X-ray tube assembly heating / cooling curves Page 74 of 141



2.12.9 Laser specifications Table 3-8 gives the specifications for the LUNAR laser. Table 2-8. Laser specifications.


Output Power Wavelength Beam Diameter at aperture Aspect Ratio Divergence Radiant Exposure Integrated Radiance Current Draw Voltage Input Safety Rating

<1mW 635nm 4x1mm 4.0 to 1 24 degrees 0.0001 W 46 W 105 mA 4-6 VDC Class II

2.12.10 Compatible components • For customers located internationally, make sure the computer is certified to local requirements such as IEC 950. The computer must meet the minimum requirements that follow: • Greater than 266 MHz Pentium • 64 MB RAM • Greater than 1GB Hard Disk • Fast serial I/O board (Lunar Part Number 7151) • 8X CD ROM • 14” SVGA monitor with at least 800x600x16-bit color (some languages may require 1024x768 resolution) • NT operating system (with service pack 6.0 and Internet Explorer 4.01 with Service Pack 2) • Disk Defragmentation Software

2.12.11 FDA certified components (US only) Table 2-6 gives components certified to the FDA for use with DPX-NT / MD+ scanners and is updated periodically. Contact LUNAR for a current listing of compatible components. Table 2-9. FDA certified components (DPX-NT and MD+ Systems number 72000 and Page greater) 75 of 141



COMPONENT

DESCRIPTION

LUNAR MODEL #

X-ray Controller

LUNAR DPX-NT (B) / MD+ single board controller

7634

High Voltage Power Supplies

Bertan1 Model: 2907 Spellman2 Model: SBD40PN280X2890

7681 7681

Tube Head Assembly

LUNAR X-Ray Tube Head Assembly

8548

Collimator

DEXA Collimator Assembly

7767

Bertan High Voltage Corp., 121 New South Road, Hicksville, NY Spellman High Voltage Electronics Corp., 475 Wireless Boulevard, Hauppauge, NY 1


2

Table 2-10. FDA certified components (DPX-NT Systems number 71999 and lower)

Component

Description

LUNAR Model #

X-ray Controller

LUNAR DPX-NT single board controller

7844

High Voltage Power Supplies

Bertan1 Models: 2411 N 2411 P

0311 or 8531 0312 or 8532

Tube Head Assembly

LUNAR X-Ray Tube Head Assembly

8297

Collimator

DEXA Collimator Assembly

2898

Bertan Associates, 121 New South Road, Hicksville, NY

1

2.13 Secondary Calibration / Daily QA 2.13.1 Secondary Calibration overview • Daily QA (Quality Assurance) tests the integrity of the scanner so operator knows it is operating within specifications. • Daily QA (Secondary Calibration) adjusts the calibration of the scanner to offset any changes due to the tube housing assembly aging, temperature varying, or when certain components are changed. Page 76 of 141



• A third type of function, QC Phantom, is another method for testing system performance. A QC phantom is scanned using standard software and results are stored (aluminum spine in lucite). • Daily QA ensures the system is operating properly by running 3 types of tests: • A peak test to adjust photon counting electronics. • A functional test that checks the indicator lights, motion system, shutter, tube housing assembly output, and detector performance. • A test that measures a secondary calibration object with different bone chambers and tissue plugs which correct for system aging and prevents long-term drifts. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

2.13.2 Starting the Daily QA (secondary calibration) Operator presses [F4] to start [Daily QA] which presents a plot of the last used parameter from the last Daily QA run. (Default display is the medium bone chamber.) At this point operator can interactively manipulate the data in QA database to create tables and graphs that can be printed. Tech presses [Start] to start running Daily QA tests. Software displays instructions to position calibration block on the table. Tech places block on tabletop with label up - aligned with laser then click [OK] to start. The UI locks out all other operations except Stop button. Scan arm moves to the "Home" position. In this case, Home is always at head of scanner for QA independent of user setting for Home. The scanner performs a scout scan to find the block. If block is not properly positioned, the scanner will prompt the user to Reposition standard more accurately. The software automatically finds landmarks within the secondary phantom. This reduces the need for exact positioning on the table top. All tests are run all of the time. The tests are executed and test results reported as each test completes. Test results include pass/fail and any quantitative information when appropriate.

2.13.3 Peak Test This test adjusts the sensitivity of the photon counting electronics. The test determines the optimal voltage setting for the detector amplifier so the maximum number of photons are detected. During this test, the shutter opens with the x-rays on. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 77 of 141

The system acquires samples sweeping over a voltage range in steps of 50 units for a full range of 500 units which is centered on the last peak setting. The detector peak test then determines the optimal voltage setting for the detector amplifier based on these curves. The actual peak setting is taken from the high energy count rates, the low energy channel is essentially blocked by the brass spillover piece in the QA standard.

2.13.4 Functional Tests The next set of functional tests consist of a shutter test and motion tests for transverse and longitudinal directions.

Beam Stop test - Measures the movement of the source shutter. A functional test checks the shutter LSW and ensures the shutter stops all photons. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Motor motion and limit switches - Each motor (transverse, longitudinal) will be run between hard limits and back to home position. If the hard limits do not engage, this is a failure. Also compare steps against predetermined scan window size. Spillover test - Measures the effect of high energy photons registering as low energy photons in the detector system. The beam passes through a brass piece that stops all low energy photons. The detector then measures the number of low energy photons detected as a measure of spillover. Spillover should be less than 13%. Spillover with the CZT detector will degrade about 0.2% per year. Spillover Stability test - As part of the secondary calibration, the change in spillover must be calculated on a per element basis and smoothed over the last 5 passing QA's. Daily QA measures actual spillover and stores it in QA database. As part of primary calibration, the spillover value used during that calibration is stored. The delta spillover calculation using the spillover from primary calibration and the running average of the last five spillover measurements. This information is in the scan file.

2.13.5 Reference Value Test The output of the x-ray tube housing assembly is measured as part of a Reference Value (old term was air) measurement. This is measured at 1.5 mA.

Reference Value measurement - The HE/LE counts are measured as the number of photons counted by detector at 1.5 ma. This value is used in all bone density calculations. It must be stored in the systems data file. • Reference value measurements will be performed at 150uA and 3000uA. These reference values will need to be stored separately for all detector elements. • Reference Value measurements for 1.5mA are actually made through lucite sections of the secondary calibration block. Page 78 of 141



Reference value ratio test - The HE/LE ratio for each reference value is calculated for each tube housing assembly current tested in reference value measurement.

2.13.6 Tissue Value Test Tissue secondary calibration • The system measures two tissue plugs (lucite and Acetron). • Store measured values for each chamber in QA database. • The system determines the%fat for two different materials with different compositions. • Three%fat values are displayed - lean, mid and fat . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• These calculated%fat values are compared against expected values and checked against limits for the mean, standard deviation. • A slope is calculated and this adjustment is used as a secondary%fat calibration to offset long term drifts in system performance. This adjustment is performed at the end of the%fat calculation.

2.13.7 BM Chamber Measurements The system acquires point measurements on the 3 bone chambers 10 times using the 1.5 mA medium scan mode. An image is created but not displayed. Using simple edge detection algorithm, place 3 ROI's and calculate measurements. The system determines the bone mineral BM and width for three chamber with different sizes and densities. • Measured values for each chamber are stored in the QA database. • These calculated BM values are compared against expected values and checked against limits for the mean, standard deviation. • A slope is calculated and this adjustment is used as a secondary BMD calibration to offset long term drifts in system performance.

2.13.8 Daily QA Results At the end of Daily QA, a report is automatically printed. If printer is not on line or fails, post an error to screen. If Daily QA fails, post an error message that says "Unsuccessful QA Recommend repeating procedure." • If a QA fails the error log will contain detailed information on the failure. Test results are saved automatically to a database. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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Appropriate secondary calibration and Reference Value information is recalculated from QA database using an average of 5 previous passing test results. This information is stored in each scan file. A view with plot of medium bone chamber is generated, and user the user is allowed to manipulate data interactively.

2.13.9 QA Database A historical record of system performance is maintained by storing key QA parameters in a database. • High (1.5mA) Results - fat is hidden - only bone results are viewable


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3

Service Software This chapter contains a discussion of the Service Software and the Error Log.


3.0 Diagnostic Software 3.0.1 To Access the Service Software: 3.1 The Tools Menu 3.1.1 Spectrum 3.1.2 Stability Run 3.1.3 Signal Monitor 3.1.4 Primary Calibration 3.1.5 Secondary Verification 3.1.6 Pileup 3.1.7 Set Download Parameters 3.1.8 enCORE Composer 3.1.9 Error Log 3.1.10 Copy Configuration 3.1.11 User Options 3.1.12 Service Options 3.1.13 Outbox 3.1.14 System File Editor 3.2 Tools / Diagnostics Menu 3.2.1 Pileup 3.2.2 Calibration Pileup 3.2.3 Spillover 3.2.4 Count Rate 3.2.5 Scanner Motion 3.2.6 Scanner Detector 3.2.7 Scanner X-ray 3.2.8 Lin/Rep 3.2.9 Limit Switch Adjustment 3.2.10 Scanner Disconnect 3.3 Diagnostic Scan Modes 3.3.1 Table Top Scan DPX-NT/MD+ Service Manual (Rev.3.3.2 3 - 2010) Alignment Scan Approved Document - LU44246ADW_r3.pdf Page 82 of 142

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3.3.3 Beam Wobble scan 3.3.4 Hacksaw 3.4 Error Log 3.4.1 Printing the Error Log 3.4.2 Troubleshooting Help software 3.4.3 Reading the Error Log 3.5 Service Options 3.5.1 Measure Tab 3.5.2 Analyze Tab 3.5.3 QA Tab 3.5.4 Serial Tab . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Figure 3-1. The Tools/Diagnostics Menu Figure 3-2. The Error Log Dialogue Box Figure 3-3. Error log entry details Figure 3-4. enCORE Troubleshooting help screen capture Figure 3-5. Sample DPX-NT / MD+ Error Log

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3.0 Diagnostic Software Note:


LUNAR Diagnostic software options are not available to the customer. This software is available to LUNAR authorized representatives only.

When the software is used in the diagnostic / service mode, the Engineer performing service must verify that the scanner is taken out of service mode before returning control of the scanner to the customer. The software will return to operators mode as soon as the software is exited and restarted. The operator mode may also be changed under the Tools/User Options menu. The Service software gives the Technician access to all areas of the DPX-NT / MD+ Software, DO NOT adjust AS settings.

• The Diagnostic Software is available through the User Options Tab

3.0.1 To Access the Service Software: • Start the DPX-NT / MD+ Software by double clicking the DPX-NT / MD+ Icon on the desk top • Double click the Tools option on the menu bar • When the drop down menu appears double click on User Options • Double click on the Systems Tab on the dialogue box • Click on Service under Display Mode • When prompted enter the password Award Note:

the password is case sensitive

• The Tools option on the menu bar will now contain Service Options, and Service scanning options will also be available under the F2 Measure Option



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Figure 3-1. The Tools/Diagnostics Menu

3.1 The Tools Menu 3.1.1 Spectrum Allows the service engineer to view and print the raw energy spectrum for the detector. The detector can also be repeaked from Spectrum.

3.1.2 Stability Run Used for the detection of arcing and testing the detectors performance

3.1.3 Signal Monitor View count rates for low and high-energy channels for the detector.

3.1.4 Primary Calibration Not used on DPX-NT

3.1.5 Secondary Verification Used in the manufacturing process

3.1.6 Pileup Used in the manufacturing process

3.1.7 Set Download Parameters Download and verify the Firmware versions for the cSBC. Page 84 of 141



3.1.8 enCORE Composer This is not a service tool - (Physical and Business Report Generator - see the enCORE Operator’s Manual for information).

3.1.9 Error Log Ability to view and print the contents of the diagnostic error log (see section 3.4)

3.1.10 Copy Configuration Ability to copy the scanners Error log, Configuration Files and / or QA Database to a drive on the host PC - useful when a host PC is replaced or when diagnostic information needs to be sent to LUNAR.

3.1.11 User Options . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Set up user configured options for the scanner.

3.1.12 Service Options Service Mode scanner configurations (see section 3.5).

3.1.13 Outbox Configure Printing, E-mail and Faxing options.

3.1.14 System File Editor Edit system settings for the enCORE software - do not alter these settings without LUNAR Customer Support authorization.

3.2 Tools / Diagnostics Menu 3.2.1 Pileup Determines Detector parameters for multiple events occurring simultaneously - not used for service.

3.2.2 Calibration Pileup Not used for service.

3.2.3 Spillover Perform and Acquire a Spillover Measurement (test of source spectrum and/ or detector resolution).

3.2.4 Count Rate Acquire and print Reference Counts (count rate of detector must be performed through lucite).

3.2.5 Scanner Motion Control manually and perform scanner motion diagnostics and motion configuration. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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•Motion Tests Tab •Limit Switch Monitor - used to verify limit switch status •Limit to Limit Test - used to verify limit switch positions • Configure check box- this box must be checked when limit to limit is run to establish the scanners range of motion (scan window). •Cable Stress Test - used to cycle Transverse and Longitudinal Mechanics - can be used to check new cables / check for binding •Home scanner - moves mechanics to Home position

•Motion Commands Tab . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

•Home Position - change Arm Parking position from head to foot does not effect where the daily QA (Secondary calibration) is performed - Move to Home - sends scan arm to home position. Note:

When the Home position is changed from the head end of the table to the foot or vice versa, the Limit to Limit test (see Motion Tests tab above) must be run with the Configure box selected.

•Move Steps - move the scan arm to a specific location on the table move Absolute moves an absolute distance from home, Move Relative - move relative to last position •Joystick and Laser - Enable and Control Scanner Motion manually, change motor speeds, toggle laser on and off •Lower portion of the screen displays the status of limit switches, scan arm position, and positioning switch (joystick) status.

•Find Block Tab •Secondary Calibration - can be used to find / verify that the scanner is able to find the different chambers on the secondary calibration (daily QA) block. THis tool can be useful for troubleshooting “cannot find Block errors” and for Transverse binding issues.

3.2.6 Scanner Detector •Detector Tests Tab •Gain Control - adjusts the gain on the AGS amplifier used in the detector peak setting - peak adjusts only the AGS amplifier. •Bias Control - adjusts the bias of the detector - bias peak adjusts both the detector bias and the AGS amplifier gain. Page 86 of 141



Note:

The bias and peak setting of the detector work together to maximize the number of counts - the bias peak adjusts both the bias on the detector and the AGS amplifier peak, peak adjusts only the AGS amplifier peak. When the AGS peak falls out of range the enCORE software will automatically perform a bias peak. The operator will not see any difference in operation, however, the Daily QA may take about 40 seconds longer.

•DCA window settings - view DCA window settings - these settings should not be edited. •Detector status - allows the service engineer to view the detector status real time - information displayed includes Peak setting Bias setting, and DCA windows. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

•Detector AGS Tab •AGS DAC control (verify AGS DAC settings), check on detector rollover, and check on channel count rates. DO NOT adjust the detector Bias, DCA windows or AGS DAC settings changes in the Detector bias, DCA windows or AGS DAC’s will change the scanner’s results. •AGS Mode - the operate / calibrate signal (disables the AGS systems so that the detector can be peaked correctly) can be toggled.

3.2.7 Scanner X-ray •X-ray Tests Tab•Manual Test - Control Manually the Shutter, X-ray on Indicator and patient Positioning laser •Automatic test - automatically toggle the Shutter, Laser and X-Ray Relay •X-Ray Source - Turn on source (ramp and make x-rays), warm up a tube head at install or replacement. •X-ray cycle test - cyclically ramp the source - (can be used to test ramping failures or for arcing)

•X-rays Tab •Ramp the kV and / or the mA of the x-ray generation system and view feedback real-time. Faults are displayed and polled real-time in the window on the right. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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•Ports Tab - view status of and send commands to cSBC ports (see section 2.4 for cSBC port definitions). •Download Tab - identical to Set Download Parameters (section 3.1.7) •Misc. Tab- not used for service.

3.2.8 Lin/Rep Not Used for Service

3.2.9 Limit Switch Adjustment Verify and Adjust Limit switch positions. Note: . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

When using Limit Switch Adjustment, DO NOT alter the default settings.

3.2.10 Scanner Disconnect Disconnect the scanner from the DPX-NT / MD+ software (reset the cSBC).

3.3 Diagnostic Scan Modes Performed under F2 Measure - only visible when the scanner is in service mode.

3.3.1 Table Top Scan Not used in Service

3.3.2 Alignment Scan Verify that the Source and Detector maintain a constant count rate in all areas of the scan table. Also useful for testing cables (see DXAP3001 Chapter 5 Appendix B)).

3.3.3 Beam Wobble scan Quantifies beam movement relative to the detector when the scanners mechanics are moving (see DXAP2010 Chapter 5 Appendices).

3.3.4 Hacksaw Not used for DPX-NT.

3.4 Error Log

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• The DPX-NT / MD+ will maintain an error log file whenever the scan table is in operation. All errors, fatal or nonfatal will be logged here. The Error log gives a brief description of the error and if possible the origin of the fault.



• The error log is one of the best troubleshooting tools for scanner malfunction. Note:

To aid in a quick and accurate response when requesting assistance from LUNAR, please have an error log available for review by LUNAR Customer Support.

The error log file is named errorlog.bin, this file is the current error log session. Older sessions are named errorlog.1, errorlog.2 and so on up to errorlog.4. When requesting help from LUNAR, E-mailing the current error log file and a description of the symptoms will aid in a rapid diagnosis (see Copy Configuration in section 3.1.10 for information on copying the error log to an E-mailable file).

3.4.1 Printing the Error Log. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Note:

The scanner does not have to be in Service mode to view or print the Error Log.

• The Error Log is located under the Tools dropdown menu. Left click on Tools / and then on Error Log.

Figure 3-2. The Error Log Dialogue Box DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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• Session - The DPX-NT / MD+ software will maintain up to 10 “sessions” - each session is up to 100 errors. •A new session is created by shutting down and restarting the enCORE software. A new session may also be started by clicking on the button •To view a session, left click on it, all errors (if present) will be shown in the box below. •The Errors list may be printed (click on print errors) or it may be searched with the Find Error button. •The details of the failure are shown when the error is highlighted and then right clicked on. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Figure 3-3. Error log entry details

3.4.2 Troubleshooting Help software This feature is found in software versions 2.26 and greater. When an error is highlighted and the Troubleshoot button is clicked on, it opens an online enCORE troubleshooting guide to assist the service engineer in troubleshooting the system by error code.

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Figure 3-4. enCORE Troubleshooting help screen capture.

How to use the Troubleshooting Help software: This Help software is based on Fault Tree Analysis of FTA. The fault trees are in an outline form. Each heading in the outline represents an “or” choice. For example, the basic fault below “Shutter will not close” has three possible causes: “Shutter stuck”, “Solenoid Return Spring not working”, or “Solenoid powered when it should not be”. Each of these in turn lists their possible causes.

Sample Fault Tree (from Prodigy Collimator): Shutter will not close I.Shutter stuck – move by hand to test A.Slotted Wheel scraping OMI/OMD board B.Shutter scraping Shutter Plate II.Solenoid Return Spring not working – move by hand to test A.Spring broken B.Spring no longer anchored III.Solenoid powered when it should not be A.FOINK problem – Test by disconnecting J1. If the shutter closes, swap the SBC. If the shutter stays open, swap the FOINK. B.SBC problem – Test as above.



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Note:

This type of analysis is meant to identify all possible causes, giving the user a complete list to work from when ruling out possibilities. If a cause is not listed in the appropriate fault tree analysis, please e-mail Lunar about the discrepancy.

3.4.3 Reading the Error Log


Figure 3-5. Sample DPX-NT / MD+ Error Log

A Sample DPX-NT / MD+ Error Log with 3 separate error conditions is illustrated in figure 3-3. An error condition or a subsystem failure does not typically generate a single error message, rather a cascade of events typically occurs (see example explanations below). Error Event 6 : The Scanner was unable to ramp the tubehead due to a mA

feedback failure, the error log entry indicates that this was attempt #5 (all five entries are in the log - only entry 5 is shown to save space). Entry (6) in the log is Unable to Ramp X-ray current. The status of the x-ray generator(s) are listed, Program, Expected Values and Feedback are all listed. From the readings listed the feedback for mA is 0.00 - causing the failure. The failure was induced by disconnecting the mA feedback at the D-MAX board on an NT(A) system. Page 92 of 141



Error Event 7 : follows with Unable to ramp x-ray current - Positive x-ray

current monitor deviation - this is the conclusion of error event 6.

The final entry in the error event is DET SBC DTR Reset this is the cSBC resetting.

Shutter failed to open is listed in the error log, the cause of the event was a disconnected shutter solenoid on a DPX-NT(A). The shutter failure is the only error log entry for the failure. Error Event 8:

Error Events 9-11: This is a cascade of errors - identified as a cascade by the time stamp - all of the errors occur within seconds of each other.

Longitudinal motion failure as the log indicates the longitudinal OMI/OMD failed to detect motion during a patient scan. This is followed by Error Event 10 , the cSBC resetting, because the error occurred during a patient scan the cSBC is reset to interrupt x-ray generation and stop the motors (fail safe condition). Error Event 11 is the host PC reading the cause of the interrupt sent to the cSBC - which was that the Longitudinal motor failed to move. Error Event 9:


Note: The cause was actually the l oss of the OMI/OMD signal - as the cSBC does not know if the motor moved or if OMI/OMD signal is lost and the probability of OMI/OMD failure is lower than a motor failure - the error message reads “Longitudinal motor failed to move”. Note: If you are unsure as to which errors belong together, start a new session in the error log, and then recreate the error condition. when this is done, only the errors involved in the error event will be in that log.

3.5 Service Options 3.5.1 Measure Tab 







Centerline Offset - enter the centerline offset in mm - (See DXAP201x Chapter 5 Appendices) Homing end Primary Calibration File - choose the Primary Calibration file - DPX-NT scanners come with a factory calibration file. The only time the calibration file should be changed / modified is if the customer needs to run 2.1x software and 2.2x software on the same system. The formats of the two calibration files 2.1x and 2.2x are not compatible.

3.5.2 Analyze Tab 

Auto Reanalyze all images



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• The phrase “Image not for Diagnosis' may be toggled off so it does not appear on the printout. DO NOT disable the phrase “Image not for Diagnosis” in the USA.

• Slope Adjustment - to enhance cross calibration between LUNAR scanners a slope adjustment may be entered. For information on cross calibration please contact LUNAR Customer Support.

3.5.3 QA Tab . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• The lockout times (in hours) for when the user is locked out of the scanning options and needs to run a QA or secondary calibration may be modified. • The warning time (in hours) for when the user is prompted”Reccomend Daily QA before measuring patients“ warning them that a QA or Secondary calibration is advised, but not required may be modified. • The maximum number of sessions may be set - 2000 is the recommended default.

3.5.4 Serial Tab • Scanner Communications •Enable or disable serial communications •Communications port selection •Communications tests - test the ability of the host PC and cSBC to communicate. Stress Communications test is a longer duration test. • Calibration - DO NOT adjust any entries in the calibration section of the dialog box with the exception of the QA block batch number. The block batch number should match the batch number on the block.

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4

Troubleshooting This chapter contains troubleshooting techniques for diagnostic failures, failing quality assurance tests, mechanical failures and imaging problems.


4.0 Diagnostic Failure Codes 4.1 Transverse Motion failure 4.1.1 Operator Induced - switch closed during scan 4.1.2 Mechanical Failures - Unusual noise or irregular motion 4.1.3 Loss of OMI/OMD signal 4.2 Longitudinal Motion failure 4.2.1 Limit Switch Tripped During a Scan 4.2.2 Longitudinal Binding 4.2.3 Loss of OMI/OMD Signal 4.3 Failure of the DCpower supply 4.4 Emergency Stop Button 4.5 Tube Head Thermostat 4.6 Communication Error 4.7 Other Diagnostic Failure Codes 4.7.1 Reasons For Invalid Diagnostic Failures 4.8 Failing Quality Assurance Test 4.8.1 Block Position 4.8.2 Beam Stop Action 4.8.3 Mean% Spillover 4.8.4 Reference Counts and Ratio 4.8.5 Ratio Fluctuations 4.8.6 Transverse or Longitudinal Mechanics 4.8.7 Tissue Value 4.8.8 Bone Mineral of the Standard Chambers 4.8.9 Symptoms of High and Low KV 4.9 Reference Counts 4.10 Arcing 4.10.1 Limit Switch Tripped During Scan 4.11 Imaging Problems 4.11.1 White, or Grey in the first or second scan line: DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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4.11.2 Femur Scan Problems 4.11.3 AP-Spine Image Problems: Probable causes 4.11.4 Broken Signal Cable 4.11.5 Loss of tube head current 4.11.6 X-Ray Relay Failure 4.11.7 Unstable AC Line 4.11.8 Arcing 4.12 Failing Alignment Test Results 4.12.1 Image 4.13 Indicator Failures 4.13.1 X-ray On LED Blinking 4.13.2 Shutter Open LED Blinking 4.13.3 Shutter Not Operating 4.13.4 End of Exposure Alarm During Scan 4.14 Communications Failures 4.15 Viewing Quality Assurance Trends 4.15.1 What to Look for in the QA History 4.16 MAX Board Troubleshooting 4.17 OMI/OMD Board Troubleshooting 4.18 SBC Troubleshooting 4.19 XORB Troubleshooting

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4.0 Diagnostic Failure Codes The following conditions halt the operations of the scanner, and generate a diagnostic failure message which is displayed on the monitor screen: All of these interrupts are detected by the cSBC

• Transverse Mechanics Failure (4.1) • Longitudinal Mechanics Failure (4.2) • Emergency Stop Button activated (4.3) • X-ray source over temperature (4.4) • DC power supply failure (4.5)


4.1 Transverse Motion failure Motion Detection cSBC / OMI/OMD fail to see transverse motion during a patient scan, an interrupt signal is generated and the cSBC resets and closes the shutter. A slotted disk at the end of the arm rotates through an infrared o beam (OMI/OMD), and pulses are sent to the cSBC board when there is transverse motion. The transverse and longitudinal motion detection system (on cSBC) is operational during patient scans and the “find block” test of the daily QA. If the problem occurs during a quality assurance, it may be high voltage arcing or a problem with the OMI/OMD. 



4.1.1 Operator Induced - switch closed during scan Cause: When scanning, a defect in the transverse mechanics or a mispositioned patient may cause one of the transverse limit switches to close when the scanner is acquiring data. Closure of a limit switch prevents further operation of the motor. The shutter will close, the shutter open lamp will go out and the end of exposure alarm will sound. Seconds later the error message will appear on the screen. Solution: If the patient is not centered on the table top or if the region being scanned is too close to a limit in transverse travel, the limit switch may be close while scanning. Re position the patient on the table, further away from the limit.

4.1.2 Mechanical Failures - Unusual noise or irregular motion



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If the Detector / Tube Head motion is irregular, or scraping noises are heard, the Transverse Mechanics may be binding. This symptom will typically be detected as a failure by the daily QA Mechanics Test. • Symptom: If the Detector Array / Tube Head is not moving when scanning check: • Mechanics are free to move • Centent • Stepper Motor

Troubleshooting Binding . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Turn off the power to the scanner and move the affected parts by hand. Feel the motion for spots where the carriages are more difficult to move. Listen for unusual noises. The following are common causes for Transverse Binding

• High Voltage Cable Routing One of the most common problems is a failure of the Source and Detector to reach the rear Limit Switch due to the Tube Head running into its own high voltage cables. These cables must have a hump formed at the Rear Longitudinal Carriage that allows the lower portion of the Tube Head to pass under the cables. The High Voltage Cables can also impede transverse motion toward the front Limit Switch. This is caused when the cables have been tied down without enough play for the Tube Head and Detector to move all the way forward. These problems should be investigated by manually tripping both Limit Switches while inspecting for cable conflicts, binding, or tension problems. • Check to see that the bottom of the Tube Head is not hitting the Transverse Centent

• Wiring In rare instances, the wires from the Shutter Solenoid and/or Fans can snag on the bolts that protrude through the frame on the foot end of the scanner. This is solved by properly tying down these wires.

• Transverse Belt The Transverse Belt should not be excessively tightened or this will cause excessive binding in the transverse mechanism. It should be possible to deflect the belt by 4 cm when it is properly tightened. Sometimes the spare belt material near the clamp on the Tube Head Carriage comes into contact with the forward gear and prevents the scanner from going all the way to Home position. Page 98 of 141

• Drive Wheels



The wheels that support the Tube Head and Detector Carriages must be adjusted so that they come into perfect contact with the Transverse Rails. These wheel are best inspected with the table top, front panel and arm covers off so one can sight down the extrusions. However, it is possible to test the wheels by preventing any wheel from turning and seeing if the carriage will still move. By preventing any wheel from turning, you should be able to tell that it slides along the extrusion while the others roll. This indicates that the wheel has not been excessively tightened down. This is least likely to be the source of transverse motion problems, as it is unlikely that the adjustment of the wheels would have become any tighter over time. They would be more likely to loosen over time and fail alignment tests (see Alignment Test, section 4.12). Adjustments can be made by loosening and rotating the eccentric bearings of any of the lower wheels.

• Gear And Pulley Positioning . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Check all appropriate gears and pulleys. Verify that the set screws are tightened and the gears and pulleys are not out of position.

• Limit Switch Positioning If the transverse motion seems to be acceptable, but the number of steps in the Quality Assurance Test is failing, check the position of the Limit Switches. On Total Body scans, a limit switch out of position could allow the Source/ Detector Carriages to hit the frame or panels before the Limit Switch is actuated.

• Transverse Motor Check the Transverse Motor for a broken wire in one of the internal coils, or a bad electrical connection to its Centent Motor Controller.

• Transverse Centent The Centent Motor Controller, if defective, will cause transverse motion problems. Sometimes the controller works well enough to acquire some scans, but it will not provide enough torque to complete every fast scan. The CURRENT SET voltage at terminal 11 on a properly operating controller should be 14 to 16 VDC (transverse motor wired in parallel). The longitudinal and transverse Centents are identical, and can be exchanged. If the problem remains, the Transverse Motor should be replaced.

4.1.3 Loss of OMI/OMD signal If the error occurs consistently on the first line of a patient scan or during the find block portion of the daily QA, and the scanner is moving in the transverse direction, then check the following:

Cause: The Interrupt signal is being lost. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


Page 99 of 141

Solution 1: The pulses that normally enter the cSBC board at J14 (the black wire at the center of the connector) may have stopped. These pulses are necessary to keep the cSBC from resetting. These pulses can be seen on a cSBC board LED. Use the DPX-NT service software (Tools/Diagnostics/Scanner Motion /Motion Commands Tab) to set the joystick speed to 50 steps, enable the joystick and watch the LED. If the OMI/OMD is working the LIght will lash when the Transverse Motor is run. If the LED flashes when the mechanics are engaged, but the error still occurs, the interrupt was invalid. Check for arcing in the high voltage system or replace the cSBC. If the LED D9 (B in figure 4-1) does not flash, 


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Verify that the slotted disk at the front of the lower arm rail is in the middle of the slot between the photo diode and photo transistor. The slotted disk must be completely flat and remain in the center of the sensor slot during its entire rotation. If the slotted disk has been in physical contact with the optical sensor, the sensor may have debris on it, disassemble this mechanism, and clean the sensor and the slots of the disk. Check the Cable running from the cSBC to the OMI/OMD for a cable break by checking the individual wires for continuity.

4.2 Longitudinal Motion failure 

cSBC/ OMI/OMD fail to see longitudinal motion during a patient scan, an interrupt signal is generated by the cSBC which resets and closes the shutter. o

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A slotted disk at the foot end of the table on the pulley for the Longitudinal Drive Belt rotates through an infrared beam (OMI/OMD), and pulses are sent to the cSBC board when there is transverse motion.

The transverse and longitudinal motion detection system (on cSBC) is operational during patient scans and the find block portion of the daily QA. If the problem occurs during a quality assurance, for instance, it may be the high voltage system is arcing or the OMI/OMD may be malfunctioning.

4.2.1 Limit Switch Tripped During a Scan

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• Cause: When scanning, a defect in the longitudinal mechanics (binding) or a mis-positioned patient may cause one of the longitudinal limit switches to close when the scanner is acquiring data. Closure of a limit switch prevents further operation of the motor. The shutter will close, the shutter open lamp will go out and the end of exposure alarm will sound. Seconds later the error message will appear on the screen.

Solution: If the patient is not centered on the table top (length wise) or if the region being scanned is too close to a limit in longitudinal travel, the limit switch may be close while scanning. Re position the patient on the table, further away from the limit.

4.2.2 Longitudinal Binding • If the scan arm fails to move when scanning check the stepper motor, and Centent, if arm motion is irregular, check for binding. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Turn off the power to the scanner and move the affected parts by hand. Feel the motion for spots where the arm is more difficult to move. Listen for unusual noises. When moving the arm longitudinally, only push on the arm column. Pushing on the forward parts of the arm can ruin Tube Head/Detector alignment.

• Cable Track The major impediment to longitudinal motion is the plastic Cable Track that runs through the trough at the rear of the scanner. This track is attached at two points: at the Rear Longitudinal Carriage and to the scanner frame (low, rear and center) each spot by 4 bolts. Also, adequate slack must be left in the cables inside the Cable Track or they will stop the arm from moving fully to the foot end. Should the Cable Track detach from the scanner frame, it will slide freely in the trough and will eventually cause trouble. This can allow the Cable Track to get in between the Rear Longitudinal Carriage and the scanner frame on the foot end preventing the tripping of the limit switch. • Front Longitudinal Carriage Dragging Check the distance between the front longitudinal carriage and the longitudinal rail with a go/nogo gauge (See installation Procedure DXAP2000 Chapter 5 appendices). The carriage should not rub the front rail, if necessary insert shims behind the front longitudinal carriage.

• Tube Head Cable Routing



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Problems at the head end of the scanner can be caused by a limit switch being out of position (thus the arm runs into the frame before the Limit Switch) or because the High Voltage Cables are tied down incorrectly where they snake around from the Rear Longitudinal Carriage to the panel under the Tube Head (High Voltage Cable Trough). If the cables are tied down too far toward the head end (at the point where the three tie downs are), they can run into the Longitudinal Motor Assembly and hold the arm away from the head end Limit Switch.

• Slip Clutch A slip clutch is part of the longitudinal motion system to limit torque. This is a feature to protect the patient should he/she pinch an arm or leg between the back side of the scanner and the Arm Column. If the Slip Clutch is set too loose, it will fail to move the belt and will just "slip" as the motor turns. This may produce the following symptoms: . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• failure of Quality Assurance scan Mechanics test • compressed image in limited areas of the image • a Longitudinal Mechanics diagnostic failure

• Gear and Pulley Positioning Check all appropriate gears and pulleys. Verify that the set screws are tightened and the gears and pulleys are not out of position.

• Limit Switch Positioning If the longitudinal motion seems to be acceptable, but the number of steps in the Quality Assurance Test is failing, check the position of the Limit Switches. On Total Body scans, a limit switch out of position could allow the Source/ Detector Carriages to hit the frame or panels of the scanner before the Limit Switch. If the mechanical stop is reached before the Limit Switch is actuated, check carefully to see which part of the Arm Assembly is in contact with the Table Assembly. The front part of the Lower Transverse Extrusion is clamped to the Longitudinal Drive Cable at the front of the scanner. If the Lower Transverse Extrusion is not clamped in such a way that it forms a 90 degree angle with the length of the table, the rollers at the front end of the Lower Transverse Extrusion may strike the end of the scan table before the Limit Switch is actuated.

• Longitudinal Motor Check the motor for a broken wire in one of the internal coils, or a bad electrical connection to the Centent Motor Controller.

• Longitudinal Centent Page 102 of 141



The longitudinal Centent Motor Controller may be the cause of a failure. The current set voltage should be roughly 9-11 volts at terminal 11 on a properly operating controller. If this voltage is not correct, replace the Centent Controller. The longitudinal and transverse Centents are identical, and can be exchanged. If the problem remains, the Longitudinal Motor should be replaced.

• Longitudinal Belt The Longitudinal Belt should not be tightened too much or this will cause the brackets holding the gears to deform at either end of the scanner. When the belt is properly tightened, it should be possible to deflect the upper and lower sides of the belt so that they touch within 8 cm of the gears at either end.

• Drive Wheels . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The rollers in front and the wheels in back that support the Arm must be adjusted so that they come into perfect contact with the Longitudinal Rails. Test them by preventing any wheel from turning and see if the carriage will still move. By preventing any wheel from turning, it should be possible to slide the carriage along the rail with one wheel dragging while the others roll. This indicates that the wheel has not been excessively tightened down. Adjustments can be made by loosening and rotating the eccentric bearings of any of the lower wheels.

4.2.3 Loss of OMI/OMD Signal • If the Scan Arm motion is irregular, or scraping noises are heard, the Longitudinal Mechanics may be binding. This symptom will typically be detected as a failure by the daily QA Mechanics Test. If the error occurs consistently after the first line of a patient scan, and the scanner is moving in the longitudinal direction, then check the following:

• Cause: The Interrupt signal is being lost. Solution 1: The pulses that normally enter the FOINK board at J (the black wire at the center of the connector) may have stopped. These pulses are necessary to keep the cSBC board from interrupting. These pulses can be seen on the cSBC. Use the DPX-NT service software (Tools/Diagnostics/Scanner Motion / Motion Commands Tab) to set the joystick speed to 50 steps, enable the joystick and watch the LED. If the OMI/OMD / cSBC is working the Light will flash when the Longitudinal Motor is run. If the LED flashes when the mechanics are engaged, but the error still occurs, the interrupt was invalid. Check for arcing in the high voltage system or replace the cSBC. If the LED does not flash, 

Verify that the slotted disk at the foot end of the scan table is in the middle of the slot between the photo diode and photo transistor.



Page 103 of 141

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The slotted disk must be completely flat and remain in the center of the sensor slot during its entire rotation. If the slotted disk has been in physical contact with the optical sensor, the sensor may have debris on it, disassemble this mechanism, and clean the sensor and the slots of the disk. Check the Cable running from the cSBC to the OMI/OMD for a cable break by checking the individual wires for continuity.

4.3 Failure of the DC Power Supply The DC power supply is only enabled when the X-ray tube is ramped, use the service software (Tools/Diagnostics/ Scanner X-ray) to attempt to ramp the Tube Head. The Red and Green LED’s on the MAX board will be lit whenever the DC power supply is up and running. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

If the LED’s illuminate and the go out: 



Measure the output of the DC power supply, and verify that it remains constant during the voltage ramping and scanning operations. Check the High voltage power supplies, insure they are not arcing (Error Log - see section 3.2) and are ramping.

If the LED’s fail to light: 

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This supply is turned on by the X-ray Relay, so verify that the Relay is closing. If not, then either the Relay is bad or it is not receiving the signal from the cSBC. Check the continuity of the cathode, the filament may have broken, MAX board TP 4, TP 5 and TP 13 should be continuous with the Tube Head control cable connected. The Tube Head Thermostat is wired in series with the Relay, so if it has opened, the Relay will not be able to close. 28 VDC should also be measured at the Terminal Block. If not, check the continuity of the wiring and refasten all connections. Also, check the wire tie-downs for excess tension they may be putting on the wires. It may be necessary to check the wiring from the Terminal Block to the MAX board and to the High Voltage Power Supplies.

4.4 Emergency Stop Button

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The Emergency Stop button is a normally closed circuit, if it opens the Emergency Stop and the cSBC will generate an interupt. • Verify that the emergency stop button is out. If it has been pressed in, press it again to release it. • If 26VDC can be measured on both pins of cSBC connector J17, the Emergency Stop Switch and the wires connecting it to the cSBC board are good and the cSBC board should be replaced. • If 26 VDC is missing, the Circuit is open between the cSBC and the Switch. • Insure the switch is functional • Check the continuity of the wires from the switch to the cSBC board. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

4.5 Tube Head Thermostat There is a thermostat inside the Tube Head. This thermostat is normally closed, but opens when the Tube Head temperature is too high. • The thermostat will close again automatically after a cool down period of usually less than 30 minutes. If 0 VDC is measured on both pins of cSBC connector J15, the Thermostat and the wires connecting it to the cSBC board are good and the cSBC board should be replaced.

4.6 Communication Error The computer is not communicating with the cSBC board. Verify communications with the cSBC in the service software (Tools/Service Options Comm tab - Test Communications). If this is unsuccessful, verify that the I/O cable from the computer to the cSBC Board is secure. Also, verify that the comm port is configured correctly (see DXPC 2000 Chapter 5 appendices) and that all required drivers are present. If all fails, the cSBC or computer serial port is defective.

4.7 Other Diagnostic Failure Codes Multiple error codes are possible. These will be displayed one after the other, but the first one displayed is probably the problem. The Error Log will always show the failures in the correct order, the others are generated as a result of the first failure.

4.7.1 Reasons For Invalid Diagnostic Failures



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Arcing of the x-ray high voltage system releases a large amount of electromagnetic energy. This energy creates noise in the electronic circuits and may cause the SBC to do unpredictable things, such as give invalid diagnostic errors. Arcing is usually accompanied by white, blue or black lines across patient scans (See Arcing, section 4.10).

4.8 Failing Quality Assurance Test See chapter 2 section 12, for explanations of the various tests that are performed during the running of the Daily Quality Assurance.


If any of the QA test results fail, none of the results are considered valid. The results will be stored in the Quality Assurance History file, but these values will not be averaged with the other results for calibration purposes. In addition, the software will prevent patient scans until a passing daily QA has been completed. Recent valid QA's are necessary for accurate results.

4.8.1 Block Position After starting a QA, the operator is prompted to place the QA standard n the table, if the DPX-NT fails to detect the Block in the correct orientation the QA will not progress. • Check Block position and orientation The scanner may not be finding the correct "Home" position. The correct "Home" position aligns the center of the x-ray beam with the center of the Brass Piece when the Standard is correctly positioned. The Air Counts must be obtained outside of the QA standard, next to the Brass Piece. If the Reference Counts are obtained with the x-ray beam passing through the Brass Piece, the Quality Assurance Scan will fail. • Verify that the scanner limit switches are set correctly with the DPX-NT home position jig (see DXAP2000 - DPX-NT Installation Procedure Chapter 5 appendices).

4.8.2 Beam Stop Action The Beam Stop Action test verifies the ability of the lead shutter to attenuate x-rays from the tube head by verifying that the Background counts when the shutter is closed are lower than counts taken through the brass piece with the shutter open.

4.8.3 Mean% Spillover An increase in the Spillover percentage over time is an indication that the detector is losing resolution, even if the Spillover test does not fail. A large change in the Spillover can be explained in some cases by standard positioning (or a small change in the home position of the scanner). If the beam is not fully eclipsed by the brass piece during the Spillover test, the Spillover value increases dramatically. Page 106 of 141

Spillover stability is a test of detector bias drift. if the detector bias is drifting, DPX-NT/MD+ Service Manual (Rev. 3 - 2010) the mean spillover value will also drift.


4.8.4 Reference Counts and Ratio During this test the baseline is established which will later be used for comparing with the values obtained during the scan of the standard. Care should be taken that the x-ray beam is not missing the standard, nor being obstructed by the brass piece on the standard during the High and Low Air Count test. The Ratio value should remain fairly constant over time.

4.8.5 Ratio Fluctuations The ratio of High to Low Channel Air Counts is the way the bone density measurement is calculated by the changes in the ratio of High to Low Channel counts. The Ratio should remain constant as long as the x-ray beam quality and the resolution of the detector remain constant. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

It is possible to view the Ratio trends in the Quality Assurance History. Check both the 3mA Ratio and the 150 Ratio to determine if the either Ratio has changed significantly. The problems which could cause a change in air ratio are: · deterioration of the resolution of the detector · current leakage through the transorbs on the XORB board · a faulty High Voltage Power Supply (kV unstable over time) · changes to the x-ray tube insert These are very difficult to diagnose by a method other than substitution of new components until the Reference Counts Ratio returns to normal. Detector deterioration or unstable High Voltage Power Supply, will usually cause the Alignment Test Scan to fail. The specification for XORB Board transorbs is that they must allow less than 0.5 micro amperes reverse bias current. At LUNAR, each transorb is measured by applying a 5 Volt reverse bias to the transorb and a 100 kW 1% resistor connected in series. The voltage measured across the 100 kW resistor must then be less than 50 mV.

4.8.6 Transverse or Longitudinal Mechanics Failure of this test is caused by one or more of the following: • Incorrect Limit Switch positioning • Defective Limit Switch • A mechanical constraint • A defective Motor • A defective Centent Motor Controller



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The values recorded for these tests should remain fairly constant over time. Variations between QA's of under 25 steps should not be a cause for concern as 1 transverse step = 0.05 mm and 1 longitudinal step = 0.1 mm, so the actual variation is only a few millimeters. If the number of steps continually increases from QA to QA, this could indicate an impediment to the scanner's motion and should be rectified (see 4.1 (Transverse) or 4.2 (Longitudinal)).

4.8.7 Tissue Value The tissue value should not be the sole failing parameter. The failure of this test is usually accompanied by problems with Bone Mineral values (see below) or Reference Counts Ratio trends (see above). If this is failing alone it is probably a problem with the counting system or high or low kV (4.8.9).

4.8.8 Bone Mineral of the Standard Chambers . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The software contains values which it expects the scanner to measure for the scan of each chamber. If the mean of the BM measurements made for the chamber does not fall within the predefined software limits the QA will fail. If the percent coefficient of variance is over 3%, the QA will fail. These failures will always occur if the Reference Counts or Reference Ratio test have deviated severely from normal results. However if the Reference Count results look normal, and the values are approximately equal to the numbers obtained during the scanner installation, then the counts may be unstable. Another cause of failing on the bone chamber measuremnts can be arcing during the QA. This can be detected by examining the QA History graphically and looking for variation of the Large BM values. Note the few data points that vary. These are the early signs of arcing. This will also be apparent (but not obvious) on the QA Results printout. The arc occurred in the third standard scan and elevated the BM values. If a customer reports a failing QA because of a bone chmaber measurement being too high, be aware that this could be an early warning of arcing. Obtain from the site the QA history file and error log for analysis. Look for variation of the Large BM values. It is very important to notice these early warning signs of arcing so that the system can be re-greased before any damage is done to the high voltage cable connectors or the tube head.

4.8.9 Symptoms of High and Low KV It has been noted in a small number of cases that defective high voltage power supplies, or an arcing tube head may produce a voltage other than 76 kV. The DPX-NT monitors kV once per scan sweep.

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Note:

:It would be prudent in both of these cases to take a positive and negative power supply, AND a tube head. Also, the XORB test points may look normal (indicating 76 KV) in each case as well. This usually occurs where the power supplies are defective and so the monitor voltages returned to the XORB may not show the true voltage. When the tube head arcs causing the voltage to go too high, then the XORB test points may indeed show the actual voltages.

4.9 Reference Counts 4.9.1 Unstable Counts . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

To examine the scanner's ability to count detector pulses consistently over longer periods of time, run the Alignment Test option from the service software program. • If the "End of Exposure Alarm" rings during the time the Alignment Test scan is running, see "Alarm Pings During Scan" in section 4.13.4. If the Shutter Open or the X-ray On lamps on the front panel blink, during the test, see section 4.13 also. • While the Alignment Test scan is running, measure the voltage at test points 1, 2, 5 and 6 of the XORB board. They should have approximately the following values respectively: -0.150VDC, 3.8VDC, 0.150VDC, and 3.8VDC. • A pure DC voltage on an oscilloscope at test point 1 and 5 of the XORB will verify that there is constant current through the filament of the X-ray Insert. • If there is AC ripple in excess of 0.2 Vpp, the power supplies should be replaced. • Start and stop the x-rays several times while observing the voltage at TP3 and TP7 of the XORB board. This is the programming voltage from the SBC, and although this voltage is dependent on the feedback information returned to the SBC, the voltages at the XORB board test points should be approximately the same each time the x-rays are produced. The AC ripple on this signal must be less than 0.2 Vpp. Replace the SBC board if the proper control signal is not present. • When the x-rays are off between scans, verify that the shutter aperture lines up with the aperture to the Tube Head beneath. Take some alignment pictures and verify that the image is a bright, rectangular image and the entire alignment box is visible. If the alignment box is not visible, the shutter Tube Head and detector apertures are not aligned. • Open and close the shutter to make sure that it returns to the same position each time. Turn the x-rays back on, and make sure that you obtain nearly the same count rate each time the shutter isPage opened. DPX-NT/MD+ Service Manual (Rev. 3 - 2010) 109 of 141 Approved Document - LU44246ADW_r3.pdf Page 110 of 142

4.9.2 No Counts When the table to the right of the peak graph on the Quality Assurance Results printout is entirely filled with zeros, use the Signal monitor program in the Diagnostics (see section 5.1) to create x-rays at 76 kV and 150 uA and open the Shutter for sampling. Then check the following items: I.Is the amber X-ray On LED illuminated? A.If it is, skip to part II. B.If not, the voltage or current ramping has probably failed. Are both the red and green LED's on the MAX Board illuminated? 1.Voltage or Current Ramping Failures If not, is the red LED illuminated? . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

a.X-ray Relay or cSBC If not, measure the output of the 28 Volt Power Supply. Check the operation of the X-ray Relay or the cSBC Board which controls its operation. If all of the above are working, the red LED may be defective. b.MAX Board Fuse If so, the fuse is blown on the MAX Board (see section 4.16). 2.If the red and green MAX Board LED's are illuminated, verify the following test point voltages: a.Current Ramping Failure • XORB TP1 is approximately 0.150 VDC. If incorrect, go to step d. If this test point is correct, verify that XORB TP5 is also approximately 0.150 VDC. If this voltage is incorrect, substitute a new Positive High Voltage Power Supply. b.Voltage Ramping Failure • XORB TP2 and XORB TP6 are approximately 3.8 VDC. If these voltages are incorrect, verify that the voltages on XORB TP3 and XORB TP7 are approximately 3.8 VDC. If TP3 and TP7 are not equal the XORB jumper at J26 is set in the wrong position. If they are equal but incorrect, test the cable from the SBC to XORB, or substitute a new SBC Board. c.X-ray On LED Test the X-Ray On LED by inserting it into the Power On receptacle. Replace if defective. d.High Voltage System

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• Current ramping has failed. If TP1 and TP5 are zero and do not change, check the polarity of the High Voltage Cables. The X-ray Insert is essentially a diode, and will not conduct current from the anode to the cathode. • If either of the test points is at 1.0 VDC, the High Voltage Power Supply is delivering as much current as it possibly can, and has automatically limited the voltage. • Check TP2 and TP6. If the voltage is approximately 3.8 VDC, the voltage has been set properly.


Feel the heat sinks on the back of the High Voltage Power Supplies. If one of the power supplies is cold, this is usually the defective one. If one is warm and the other is hot, replace the hot one. The best troubleshooting technique may be to substitute power supplies. • If either TP2 or TP6 are incorrect, the possibility exists that one of the High Voltage Cables or the Tube Head is shorted. The short may be possible to find with an ohm meter, but often it takes several kV to break down the defective component. It will be difficult to troubleshoot this problem by any method other than part substitution. Do not attempt to ramp the power supply above 50 kv without a cable connected, or arcing will o ccur near the connector.

• Ramping between 40 and 50 kV is a good way to determine whether the power supplies are able to increase voltage from 0 to 50 kV.

4.9.3 Decreasing Reference Counts A long term, continuous decrease in the Reference Counts unaccompanied by a change in Reference Ratio is a serious problem. A count rate of at least 500,000 Low Channel Reference Counts is necessary to maintain precision of results when scanning thick patients. Reference Count values should change by less than 10% from the day of installation. The possible causes are:

I.Lead Filings - Shutter Wear A rough edge around the shutter aperture may be wearing away on the tube head below. The lead filings fall off the shutter aperture and gather on the filter below, causing a reduction in x-rays over time. Any wear should be easily visible on the underside of the shutter paddle. If there is visible wear, the lead dust must be removed from the top of the filter. The Collimator assembly must be removed, the filter cleaned, and then the Collimator assembly reinstalled and realigned. II.A Change in Current Control Settings DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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Use the Signal monitor option of the service software program to produce xrays (Tools/Diagnostics? Scanner X-Ray). Select 76 kV and 750 µA operation. • Verify that the cSBC is properly controlling the current. TP11 of the MAX board should be approximately 0.75 volts. This voltage is dependent on feedback information from the power supplies, which makes it difficult to troubleshoot by any means other than SBC substitution.


• Check the current through the X-ray Insert. The absolute value of the voltage at test points 1 and 5 on the XORB board is proportional to the current through the X-ray Insert. 1 millivolt is equal to 1 micro-ampere of current. A current setting of 750 µA should give a reading of 0.750 VDC at test points 1 and 5. If either of these voltages vary from the expected by more than 10 millivolts, the MAX board could be at fault. If TP1 and TP5 are more than 15 millivolts apart, substitute new high voltage power supplies.

4.10 Arcing The X-ray Tube Head Insert is an evacuated glass enclosure. An AC current is applied to the filament inside the insert. It glows like the filament in a light bulb, and electrons are boiled off into the evacuated space. A high voltage is applied between the anode and the cathode causing electrons to rush toward the anode, striking it and creating x-rays. As long as the insert is properly evacuated, there can be no internal arc. However, no insert can be totally evacuated and impurities can be ionized creating a lightning like effect; arcing. During the arc the resistance of the insert is dramatically decreased and a large amount of current flows. • The significant amounts of electromagnetic energy released inside the scanner can cause problems with the electronics of the scanner system and may result in abnormal operations of the scanner. An arcing scanner will have one or more of the following symptoms: • complete lock up of the system • a diagnostic error code message which is undefined or inappropriate • a vertical stripe or artifact in the image of the patient's scan (effects all 16 detectors at once) • Transverse Motion Failure message. To specifically locate the source of an arc, it is necessary to find out which high voltage power supply provides the excessive current. This may be done by recording the power supply current monitors at TP1 and TP5 of the XORB board with a storage oscilloscope. An arc typically draws 1.5 mA from the power supply for about 1 ms. The trigger voltage should therefore be set at 1.5V for TP1 and for TP5. Page 112 of 141



• Arcing can also occur inside the high voltage connectors. This will usually result in a plainly visible black or brown carbon track through the grease on the connector. In any case, once the high voltage connectors have been removed from the Tube Head and the power supplies, they should not be re-connected without first being cleaned and regreased (see procedure DXSE0002 in the chapter 5 appendices). • After cleaning the old grease off of the connectors, they should be carefully inspected for carbon tracks. Look for these tracks on both the rubber cable connectors and on the phenolic sockets of the Tube Head. If such tracks are found after cleaning, the following are the options for returning the scanner to service:


• If carbon tracks are found on the rubber cable connectors, they can be removed by excising the damaged section with a sharp blade. Severe tracks can burn quite deep into the rubber, so care must taken to remove all the damaged rubber. After the carbon tracks have been removed, additional grease must be used when repacking the connection to fill in the volume of the removed rubber. • If the above procedure requires too much rubber to be removed, or the carbon track looks very severe, another option is to replace the high voltage cable. • Arc tracks will be impossible to see on the sockets in the Tube Head. Therefore, if arc tracks are seen on the rubber cable connectors, the sockets should be sanded with emory cloth as a precaution. After sanding the socket, remember to flush the socket with cleaning solution to remove any particles. • If the tracking inside the socket is too severe or the carbon track cannot be removed, another option is to replace the Tube Head. Note:

IT IS VERY IMPORTANT TO REMOVE ANY CARBON TRACKS ON THESE SURFACES! Carbon tracks that are simply covered by grease or not completely removed will still provide a path for arcs to follow.

4.10.1 Limit Switch Tripped During Scan If a Limit Switch is tripped during an install test, verify the Limit Switches' location with the Service Software (Tools/Diagnostics/Scanner Motion). If this problem occurs any time after install, see the problem description below. If the transverse mechanics of the scanner become imprecise, it may cause a Limit Switch to be tripped during a scan. This will usually only happen during a total body scan or during an Alignment Test test since both of these scans involve full-width scanning. Once the switch is closed, the motors stop, the End-of-Exposure Alarm sounds, the amber SHUTTER OPEN lamp turns off and after a few seconds a Diagnostic Failure appears on the screen. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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• During full-width scanning, the Detector Carriage comes very close to the Limit Switches, so any imprecision will cause a Limit Switch to be tripped and the scan will be aborted with a Diagnostic Failure message for Transverse Motion Failure. A cause of this problem is a loosening of the first drive Reduction Belt which connects the Transverse Motor to the first Reduction Pulley. This loosening causes the belt to "walk" on the pulleys causing enough imprecision in the motion to trip a switch. To tighten the belt, first remove the Pulley Shroud and loosen all four nuts that hold the motor in place. Then, while holding the motor such that the belt is pulled taught, tighten the nuts to secure the motor in place. Replace the shroud and test the scanner (an Alignment Test test works well).


If the Tube Head cables come into contact with the cable bundle entering the cable track, it may be impossible for the scanner to complete all of the necessary transverse steps away from the operator. Consequently, on each scan line the detector will move closer to the front transverse limit switch, and the switch may be eventually closed. Form the cable bundle exiting from the cable track into an arch such that the Tube Head cables will move under the arch rather than running into the bundle. This arch must not be too high. If it is, there will not be sufficient slack in the Tube Head cable bundle to allow the Tube Head to move to the front transverse limit switch. Also, if the arch is too small, it may cause too much slack when the Tube Head is at the forward side of the table. This causes the Tube Head cable bundle to rub against the inside of the front panel causing a scraping noise to be heard. If the above does not solve the problem then check the other mechanical components. Electrical components that could cause such a failure are the Centent Motor Controller, the Transverse Motor, the FOINK board or the SBC board.

4.11 Imaging Problems 4.11.1 White, or Grey in the first or second scan line: The software is not perfect in its ability to determine the correct grey level of the entire scan based on the first line of data. Sometimes the grey levels will be set incorrectly during acquisition. During analysis the grey level is easily adjusted to give a good image, and the results are not affected by this imaging problem. This problem is most often found on very thin patients. Adding extra tissue equivalent material (rice bag or saline solution) to a very thin patient may be all that is necessary to cure the symptom.

4.11.2 Femur Scan Problems Most image discontinuity problems occur in femur images performed at 3 mA on thin or osteoporotic subjects. These lines usually occur in the trochanter area where the x-ray beam is least attenuated by tissue.

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These lines are caused by Automatic Gain Stabilizer (AGS) trying to adjust the input signal which is at an excessively high count rate. However, the AGS is not at fault, and the correct action is for the customer to attenuate the x-ray beam. Lunar normally recommends placing a rice bag (on its side to create 12 cm of patient thickness in the x-ray beam) along the side of the patient's thigh for thin or osteoporotic patients.

4.11.3 AP-Spine Image Problems: Probable causes • the shutter closes (causes the shutter open lamp to go out, and the End of Exposure Alarm to sound). • increase or reduction of high voltage to the detector (causes horizontal artifacts in the image). • loss of the signal from the detector (this effects all 16 detectors at once) . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• loss of current to the x-ray insert filament (28 volt power supply error message, the orange lamp to go out, and the End of Exposure Alarm to sound). • bad x-ray relay contacts (providing power to tube head power supplies) • reduction in AC Line voltage • loss of proper high voltage on the x-ray tube • faulty operation of the AGS system (white lines are short and found only where scan lines move from air into tissue). • arcing (may cause vertical artifacts in the image)

4.11.4 Broken Signal Cable The cables which carry the voltage to the detector and return the signal from the detector array are part of the upper and lower cable bundle assemblies. Any break or significant pinch of the cable can cause reduction in counts in either or both channels. This could result in horizontal artifacts which effect all 16 detectors at once.

4.11.5 Loss of tube head current The tube head control cable contains the wires which provide power to the filament transformer. If the wire to the transformer center tap breaks, the xrays will stop, the orange lamp will go off, and the end-of-exposure alarm will sound. If either of the other two wires break, the MAX board fuse will blow. Always ask the operator if a "ping" sound (the end of exposure alarm) is heard, and whether the Shutter Open or X-Ray On lamp turns off. In the case of a tube head current problem, the X-Ray On light will turn off.

4.11.6 X-Ray Relay Failure See section 4.16.

4.11.7 Unstable AC Line



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If the customer's AC line conditions are unstable, voltages 11% below the scaners AC input configuration will begin to drop the high voltage on the x-ray tube. The counts will drop significantly with only a change of a few kV. However, this normally causes black or dark grey lines in the scan image.

4.11.8 Arcing If the tube head is arcing, the arcs will be more likely to occur at the higher current settings. Arcing generally also causes other strange symptoms such as: • Scanner stops in the middle of a patient or QA scan with no error message or with transverse mechanics fail • The QA scan fails intermittently on bone chamber measurements . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• The scanner periodically leaves the message on the screen "Starting Xrays Please Wait" for a longer than normal period of time (more than 10 seconds) If you see arcing symptoms, try the following service action:

1.View the Quality Assurance History (see section 4.15). In particular note the trend in BM Values as discussed in the Failing QA's section of this chapter. If there is evidence of failures in the mean BM value:

2.Repack the high voltage connections as described in the chapter 5 appendices. Note if an arc track is visible in the insulation compound. 3.Replacement of the tube head if no arc tracks are discovered, or if the repacking of the connectors does not eliminate all arcing symptoms.

Summary Except for the x-ray relay, the cause of the problem will be difficult to find. Try to obtain some additional information. If the customer is hearing the end-ofexposure alarm, or seeing the yellow x-ray on lamp flickering, you can deduce the tube head control cable is bad. Likewise, it is possible to decide on the shutter/collimator/fan cable. In the case of no alarm or lamp indications, or in the case where large deviations occur in the peak, the upper and lower cable bundles should be replaced, as problems with the coaxial cable will be too expensive to troubleshoot.

4.12 Failing Alignment Test Results 4.12.1 Image The Image is a graphic illustration of the counts recorded during the Alignment Test. A good image has a black field with evenly distributed grey dots and perhaps a few randomly distributed dots of various colors (green or blue usually). Page 116 of 141




Figure 4-6. Failing Ailigment Test

A poor Deviation Image will have lines, streaks or spots (indicating counts higher or lower than expected). When the image is analized, click first on points and then back to results, this will typically point type failing points (they will have a yellow box around them). • The information tab (see figure 4-2) will show the test outcome (pass / fail). • Lines or streaks going longitudinally in the image indicate an alignment problem. Recheck the alignment of the scanner including the levelness of the scanner. Also, check the scanner frame for any bending that may have occurred at the site or during shipment. • Lines or streaks going transversely across the Alignment Test image indicate a problem with the AGS, on the Detector Daughter Board in the detector array. Again, replace parts until a passing Alignment Test is obtained.



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• Troubleshooting tip: if the Alignment test can be run with the Alignment Aperture on, this will make the test more sensitive as the beam will be further collimated to the exact size of the detector. Any failures (beam straying off the detector) will be exaggerated.

4.13 Indicator Failures 4.13.1 X-ray On LED Blinking The amber X-RAY ON LED should glow steadily once it is illuminated, until the x-rays are turned off. If the X-RAY ON LED blinks while the shutter is open for a patient scan, the End of Exposure Alarm should sound.


The amber LED is controlled by a comparator on the FOINK Board. This LED illuminates when approximately 40µA (or greater) of current is passing through the X-ray Insert. On Spellman system scanners the amber light may appear to fade out slowly when x-rays are ramped down. This due to the Spellman power supplies bleeding off current and is not a problem. If the voltage ramping fails, the High Voltage Power Supplies must be shut completely off before a second ramping attempt is made. If the amber X-RAY ON LED turns on momentarily, then turns off for a few seconds before coming on steadily, the system is having difficulty ramping the high voltage. One of the High Voltage Power Supplies may be defective. The SBC does not monitor the Insert current once the proper level has been reached. Therefore, if the current to the Insert is interrupted, the SBC will not recognize the problem and will not alert the computer, or terminate the exposure. If the X-RAY ON LED blinks once the x-ray high voltage has been set, there must be a problem in one of the following areas: • Tube Head Control Cable-The most likely cause of an intermittent problem in this circuit is a broken wire in the Tube Head Control Cable. The Red wire is most likely the broken one, as a broken blue or black wire should blow the MAX Board Fuse. Turn the scanner off and test for continuity between MAX Board test points TP4, TP5, and TP13. • MAX Board-The MAX Board may be operating intermittently. Substitute a replacement MAX Board.

4.13.2 Shutter Open LED Blinking The amber Shutter Open LED is controlled by the Limit Switch on the Shutter/ Collimator Assembly. If the Limit Switch is defective or improperly adjusted, the Shutter Open LED may be switched on and off. This will usually be accompanied by the sound of the End of Exposure Alarm if an exposure is underway.

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If the Shutter is actually opening and closing intermittently and uncontrollably, the problem is either on the FOINK, or a broken wire between the FOINK and the Shutter/Collimator Assembly. Remove connector J11 from the FOINK Board and measure the resistance between pin 5 and pin 6. This will be a measurement of the resistance of the Shutter Solenoid and the cable through the Cable Track. If the problem occurs on every scan, run a scan while making this continuity check. If the cable and solenoid seem to be working properly, substitute a new FOINK Board.

4.13.3 Shutter Not Operating If the Shutter Solenoid will not open, the problem may be caused by one of the following:


• The Shutter Open LED-If the Shutter Open LED fails, a properly operating FOINK board will prevent operation of the Shutter Solenoid. Check the LED for continuity, replace it, or substitute a working amber LED temporarily. • Solenoid Cable-Remove J11 from the FOINK Board and check continuity between pin 5 and 6 (see Shutter Open LED Blinking above). • FOINK Board-Replace the FOINK Board.

4.13.4 End of Exposure Alarm During Scan If the sharp "Ping" sound of the End of Exposure Alarm is heard during a scan, look at the computer display to see if a Diagnostic Failure Code is being reported. If so, see section 4.1. If no Diagnostic Failure Code is reported, the scanner may still be in motion continuing with the scan. Abort the scan and remove the patient from the table. In any case, note the status of the SHUTTER OPEN light and the XRAY ON light. • Both the SHUTTER OPEN light and the X-RAY ON light are on and steady. This would indicate a faulty FOINK board. Replace it The SHUTTER OPEN light is off. This could indicate the following: • The LED becomes defective during the scan and since the shutter solenoid and this light are wired in series, the Shutter closed and the Alarm sounded. • The cable to the amber Shutter Open light broke during the scan with the same result as above. • The shutter solenoid failed and the Shutter closed followed by the Alarm sounding. • The FOINK is faulty. • The SBC is faulty. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)

The X-RAY ON light is off. This could indicate the following:


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• X-ray production has halted. This turns off the X-ray On light and sounds the Alarm.

4.14 Communications Failures Should the scanner, host computer and or Detector Mother Board lose communications with each other, there are a number of things to check: A good troubleshooting tool is the COMM test in Tools/Service Options COMM tab. Check


• the I/O cable connections at the serial port on the back of the Host computer and at the cSBC. Be sure both connections are tight and that the thumb screws are used to hold the connectors firmly together. • inspect the connector on the cSBC. This connector is very fragile and may have been damaged. Be very careful when connecting the I/O cables to the SBC. • Check and inspect the Signal Cable input at the cSBC • Check the Connection at the Detector Mother Board and the Bulkhead, where the two halves of the signal cable meet. • Verify the power LED’s on the cSBC are lit (See section 4.19) If the ports are properly configured and all power is present, and communication still fails, then the probable causes are: • A faulty I/O cable. • A faulty cSBC. • A faulty serial port / serial port card. Replacement of these parts is the best troubleshooting method.

4.15 Viewing Quality Assurance Trends DPX-NT software includes the capability to view, print or graph data contained in the Quality Assurance database. View and print display selected results of many of the tests run during the Daily Quality Assurance in tabular form. The graph feature will graph the results of only one of the Quality Assurance parameters. All features allow for the user to select the time period to be examined. Page 120 of 141

4.15.1 What to Look for in the QA History DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


All categories should remain steady over time. Check the PASSED column for failed QA’s. If a failing QA is found, try to determine the cause, including operator error. The limit for % Spillover is 13%. If any sudden jumps are noticed in the values of any of the categories, determine first if these are due to service work such as a Tube Head replacement. If service work causes a shift in the QA values, then compare present values to those obtained only after the service.

4.16 MAX Board Troubleshooting . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

The MAX board controls the current through the X-ray Insert in the Tube Head. DPX-NT scanners use MAX version 02B currently. The current at a given kV across the insert is a function of insert filament temperature. The MAX board adjusts the current by regulating the filament temperature to provide the proper current as set by the SBC. The relationship is Insert µA X 1000 = SBC input (in volts DC), so for an SBC input of 5VDC, Insert µA = 5000. The Positive High Voltage Power Supply has a current monitor output (mA MONITOR); the voltage at this output is proportional to the current passing through the X-ray Insert. This monitor voltage is connected to the MAX board as feedback (mA FEEDBACK). What to look for • Make sure that all connectors are fully seated. • Check Lemo connectors for loose parts. • Check for loose wires on the insulation displacement connectors. • Check the position of the shorting jumpers on pin headers JB1, JB2, and JB3 for: Be sure pins 1 and 2 are connected as indicated by silk screen. When the X-ray Relay is on, both the red and green LED's on the MAX board should be illuminated. If both are out, no power is getting to the MAX board. If only the red LED is lit, then the MAX board fuse is burned out or missing.

Electrical tests When the board is powered up, and x-rays are being generated, the following measurements may be performed: With a VOM set on 200 VDC, you should measure about 18 to 21 VDC on TP's 4, 13 and 5 referenced to TP3 (GND).



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Note: If an oscilloscope is available, you should see about 18 to 21 VDC on TP13. However, TP 4 & 5 should have a 36 to 42 volt peak square wave. A VOM will show the average value of the square wave, i.e. 18 to 21 VDC.

4.17 OMI/OMD Board Troubleshooting The OMI/OMD board, being a rather uncomplicated device, has little in the way of things to watch for in installation and use. There are three such boards, one on the Front Longitudinal Carriage (transverse), at the foot of the scanner on the longitudinal idler shaft (longitudinal), and on the collimator (shutter open detect).

What to look for 






Check the connector to each board for proper seating. Examine the area where the wires attach to the board itself; it is possible the may fray or break. Insure that the interrupter disk does not rub against the plastic detector housing. If it does, adjust by loosening the two machine screws that attach the plastic detector, reposition the detector and re-tighten the screws.

Electrical tests The signal from the OMI/OMD board is nominally rectangular in shape. The signal is generated when the Interrupter Disk alternately passes and occludes a light beam between the two posts on the photo-transducer. With the beam occluded by the disk, the output signal should be about 5 VDC (close counts). When the beam is allowed to pass through a slot in the disk, the signal output is near ground potential (see FOINK troubleshooting 4.17).

Symptoms of possible OMI/OMD failure 

Scanner shuts down at the beginning of a patient scan.



Scanner shuts down unexpectedly during a scan.



Either condition above should be accompanied by a Diagnostic Failure Transverse or Longitudinal (see section 4.0).

4.18 SBC Troubleshooting The SBC consists of a single circuit board that uses the 8032 microprocessor with a RS-232 interface to the Host PC The SBC is located on the electronics pan in the front center.

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What to look for • Green LED (C in figure 4-5) is on then you have +5VDC to the board. • Red LED (A in figure 4-5) is on then you have +12VDC to the board. • Amber LED (B in figure 4-5) is on then you have -12VDC to the board. • Red LED (E in figure 4-5) is the DTR reset line, when this LED is lit, the Detector, FOINK, or SBC are detecting an error. When the DTR Reset Line is lit:

• Check the Signal Cable . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Go to Tools - Service Options - Communications Tab - test communications • Red LED (D in figure 4-5) the scanner Reset, when this LED is lit, the communications with the Host PC are in Reset. • Verify port settings on the Host PC (See DXPC 2000, chapter 5 Appendices) • Verify communications cable • Green LEDs (G and H in figure 4-5) flash when data is being received by the SBC • Green LED (F in figure 4-5) is not assigned a function at this time. The reset button near the communications cable connector causes a reset signal at the SBC microprocessor. Also, disconnecting the serial cable will cause a reset state until the cable is re-attached and communications reinstated.

4.19 XORB Troubleshooting The XORB board routes a number of important signals to the rest of the system and protects the system from transients by shunting them to ground with transorbs.

What to look for • All connectors firmly seated. • Check to see that all wires and cables are firmly affixed to their respective connectors. Pay particular attention to Lemo connectors, since the jam nuts on the connectors are prone to be loose. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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• Check and tighten, if necessary, all mounting screws for the XORB board.

Electrical Tests • Measure impedance between XORB ground plane and the electrical pan. It should be less than an ohm. • There should be no low impedance (less than 10 ohms) reading between any signal or signal ground and chassis ground on the XORB when the as-associated signal connectors are disconnected.

The following test points should have the following readings: Table 4-11. XORB Test Points . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Test Point

kV

mA

Limits

TP 1 TP 5 TP 1 TP 5 TP 2 TP 6

76 76 76 76 76 76

.750 .750 3.00 3.00 .750 .750

0.74 - 0.76 0.74 - 0.76 2.97 - 3.03 2.97 - 3.03 3.76 - 3.84 3.76 - 3.84

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5

Service Procedures This chapter contains procedures for testing and replacing parts.


5.0 Reloading LUNAR Software 5.1 Peaking the Detector 5.1.1 Peaking Procedure 5.2 Tube Head Replacement 5.2.1 Shelf Life 5.2.2 Mounting The Tube Head 5.3 Lower Cable Bundle Replacement 5.3.1 Procedure 5.4 Upper Cable Bundle Replacement 5.4.1 Procedure 5.5 Tube Head Control Cable Replacement 5.5.1 Procedure 5.6 Tests to Perform after Service

General Safety Precautions Ionizing Radiation Exposure: When power is applied, this equipment may generate ionizing radiation. Take precautions that no part of the body passes through the x-ray beam when the equipment is energized. Avoid scatter radiation during warm-up and testing by maintaining a safe distance from the x-ray beam. See the Safety and Specification manual for equipment appropriate distance and other precautions regarding ionizing radiation. All operators must be properly trained regarding ionizing radiation and take adequate steps to protect against injury. Electric Shock: This equipment contains high voltages. When the tabletop/panels/ shrouds are removed, visually confirm that power cord is unplugged and remains unplugged until power is required to complete the procedure. When servicing while energized, take precautions to prevent electric shock. Moving Parts and Pinch Points: Avoid moving parts and pinch points (e.g. belt/pulley, arm/back rail, green wheels/rail). Sharp Edges: Take precautions to prevent injury from contact with component edges (e.g. OMI/OMD wheel, arm slot cover). Hot Surfaces: Keep hands clear or allow components to cool before servicing. (e.g. stepper motors, hard drives, power supplies and microprocessors). Heavy Lifting: Obtain help lifting or moving any object weighing over EHS limits. Ask for assistance when maneuvering awkward objects (e.g. tabletop). DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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Laser Radiation: Do not stare into the laser beam at any time. The reflection from the tabletop or shutter/collimator assembly is sufficient to determine if the laser is on. Follow appropriate Lockout/Tagout procedures as described in MyLearning training course GEMS-EHS-LOTOAth. Wear appropriate PPE (Personal Protective Equipment) while servicing the equipment, e.g. eye protection and steel-toe/composite-toe shoes.


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5.0 Reloading LUNAR Software It is sometimes recommended in answer to a particular problem that the software be reloaded. This can be accomplished by locating the latest version of the Lunar Software. Please note, it may also be necessary to have the customers system ID number and feature code. Note:

BE SURE OF WHICH VERSION OF SOFTWARE IS PRESENTLY BEING USED! RELOADING OLDER SOFTWARE CAN DESTROY IMPORTANT DATA.

• The about tab under the help menu of the Lunar DPX-NT Software shows which version is presently on the system. • Insert the Lunar System CDROM into the CDROM: drive . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

• Double click on the My Computer icon on the Windows NT desktop • Double click on the CD ROM Drive with the LUNAR DPX-NT CDROM in the drive • Double click the Software Installation ICON • Follow the instructions on the screen until a message is displayed confirming a successful software load. Note:

When new versions of software are released they may not be loaded in the above manner. BE SURE TO FOLLOW THE LOADING INSTRUCTIONS THAT ACCOMPANY ALL SOFTWARE UPDATES.

5.1 Peaking the Detector The DPX-NT Detector may need to be repeaked, this is a good diagnostic tool to use when a detector is suspect. The actual peak setting of the detector is done in the software.

5.1.1 Peaking Procedure 1) Go to the Service Mode of the DPX-NT Software, open the Spectrum Option (Tools/Spectrum) 2) Place the brass spillover piece on top of the collimator aperture. 3) Click on the Peak button in the DPX-NT Software toolbar. 4) Verify that all values are 2000 +/- 600.



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5.2 Tube Head Replacement When a replacement Tube Head is sent to a site in the field for replacement, it is not ready for immediate installation into the scanner. Some parts from the old Tube Head must be transferred to the new Tube Head (see list below and figure 5-1). These parts are: 1) tilt bar 2) lead ring (around filter area) 3) lead wrap 4) fan bracket . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

5) nuts, bolts and washers 6) collimator positioning hardware 7) the collimator assembly.

Figure 5-7. DPX Series Tube Head components

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Verify that all necessary parts have been transferred to the new Tube Head before shipping the defective. LUNAR has received defectives with the lead DPX-NT/MD+ Service Manual (Rev. 3 - 2010) ring, for example, still in them.


5.2.1 Shelf Life Many distributors have asked about the shelf life on the Tube Heads in their stock. The shelf life of the Tube Head is not accurately known, but we feel at this time that it is over two years. Perform the following Tube Head inspections on all replacements before mounting them: 1.Check the shelf for oil spots which would indicate that the Tube Head has a leak. If oil is discovered, return the Tube Head for warranty replacement. 2.Shake the Tube Head and listen for the sound of an air pocket or bubble inside. If a bubble is discovered, return the Tube Head for warranty replacement. Note:


If a Tube Head has been on the shelf for three weeks or more, perform the warm up procedure described in Procedure DXAP2001 DPX-NT Source Detector Alignment.

5.2.2 Mounting The Tube Head Use procedure DXSE0000 in this chapter's appendix for repacking the new Tube Head's high voltage connections, and refer to the installation procedures, DXAP2001 and DXAP2002 (also in this chapter's appendix), for tube head mounting and alignment procedures.

5.3 Lower Cable Bundle Replacement Necessary tools: • 1/8" and 5/32" Hex Wrench, • Small Screwdriver • Diagonal Cutters • 3/8" Wrench • Large and small wire ties.

5.3.1 Procedure 1.Shut off the power to the scanner. 2.Take off the table top by removing four screws (two at each end). 3.Remove the head and foot end panels. At the foot end of the scan table unplug the A/C power cable to the scanner. 4.Move the scan arm to the head end of the table. 5. On your new lower cable bundle, use a diagonal cutters to cut the wire ties holding the cable together, also unfold and read the LUNAR SERVICE NOTES attached to the new cable bundle. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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6.Lay the new cable bundle flat out on the floor. Locate the end with the (2) 16 pin connectors and the yellow and orange Lemo connectors, this is the end that connects to the bulkhead, this is the end to start the install action from. 7.Locate the bulkhead on the scanner. There are (3) wire ties that hold the cable bundle in place between the bulkhead and the cable track. Before cutting any wire ties note the way the cable bundle is tied down and the way the cable lays before it enters the cable track. The new cable must be fastened in the same position and lay the same way. 8.Carefully cut the (3) wire ties between the bulkhead and the cable track with your diagonal cutters. Disconnect the large RS232 connector (Detector Signal Cable) by unscrewing the two screws on the connector. 9.Next disconnect the two white 16 pin molex connectors. These connectors have a catch lock located in the center of the housing which must be depressed to disconnect them from the bulkhead. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

10.If you try to remove the cable bundle by pulling it back towards the cable track you will notice a 3 conductor gray wire cable tied to the high voltage cable bundle. This wire carries the transverse optical interrupt signal from the front carriage (we will refer to this wire as the OMI/OMD cable). To find the location of the OMI/OMD board and the front carriage follow the OMI/OMD cable. On your new Cable bundle the OMI/OMD wire is connected through the bulkhead. 11.To remove the OMI/OMD cable push the x-ray tube head all the way to the outside of the scanner (patients left side), then notice the clearance between the front panel and the high voltage cable bundle connecting to the x-ray tube head and the way the cables are tied down as you will need to wire tie them back the same way. 12.Now you can cut the (4) large wire ties and the (2) small wire ties that hold down the high voltage cable bundle and OMI/OMD cable. Then you can pull the lower cable bundle back to where it enters the cable track. 13.Next take your small screw driver and pry open (20) of the cable track plastic retaining clips that hold the cables into the track. These clips pivot at the back of the cable track and can either be removed or left in the open position so the cables can be removed. 14.Pull the old cable bundle out of the cable track towards the foot end of the table. 15.Now install the (3) conductor OMI/OMD cable from the bulkhead to the OMI/OMD BOARD. To do this you must remove the white 16 pin connector from the bulkhead labeled bulkhead 2, this connector is a part of the upper cable bundle and the new OMI/OMD cable will connect into this housing. Note the position of the wire tie that holds the upper cable bundle in place and then cut it in order to pull the connector out to install the OMI/OMD cable. Note the orientation of the existing terminals in this bulkhead connector as they slide and lock into the connector in one direction only. Where the wires enter the connector each hole is numerically labeled. Put the green wire into hole # 11, and the black wire into hole # 9, and the red wire into hole # 1.

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16.Slide the connector back into the bulkhead bracket the way it came out and fasten the upper cable bundle with a large wire tie the way it was before the original wire tie was cut.


17.Route the new OMI/OMD cable in the same position as the previous cable and connect it to the OMI/OMD board. Then tie the high voltage cable bundle and the OMI/OMD cable down to the high voltage cable trough,(there are three large wire ties near the bulkhead, two large wire ties put together to tie the high voltage cables down at the center of the high voltage cable trough, and two small wire ties to anchor the OMI/OMD cable down to the Bracket before it connects to the OMI/OMD board). Before tightening the wire ties assure that the proper clearances and no stress is applied at any of the connectors or wires. Tighten the center cable ties first (two large wire ties put together and located at the center of the high voltage cable trough). Be sure the high voltage cable bundle does not hit the front panel when the tube head is all the way toward the outside of the scanner (patients left). Then tighten the three wire ties near the bulkhead making sure that the high voltage cables do not hang over into the cut out space on the high voltage cable trough as they may hit the longitudinal motor bracket and cause positioning problems. 18.Take the new cable bundle and connect it to the bulkhead by routing the cable bundle the same way as the replace cable bundle, (note the connectors are labeled bulkhead 1 and bulkhead 2) and fasten the cable bundle down in the three spots between the cable track and the bulkhead with wire ties. Lay the new bundle down into the cable track making sure all the cables lay parallel to each other. Start replacing the clips to the cable track as far as you can. Continue the process: remove a few clips, extract the old cable bundle, add in the new cable bundle, and replace the clips. 19.To finish removing the old and installing the new cable bundle in the lower portion of the cable track you must remove a screw located at the end of the cable track. To do this use a 1/8" hex wrench and a 3/8" wrench. Once you remove the screw you can lift the cable track out of the channel it rides in and finish prying open the remaining clips. Remove the old cable bundle until it reaches the cable entrance hole, where all the cables enter the electrical pan area. Then finish installing the new cable bundle until you reach the cable entrance hole, finish clipping all the clips and then replace the cable track hold down screw (do not tighten the screw at this time). 20.Locate where all the wires from the old cable bundle terminate on the electronics pan. All of the wires are labeled except for the wires that go to the terminal block. Here is a list of wires that must be disconnected before removing the cable bundle from the pan area. cSBC(J-5), FOINK(J-17), FOINK(J-12), FOINK(J-14), FOINK(J-5), FOINK(J-8), PMT/AGS(J-11)(J-11 is the yellow Lemo connector), the orange Lemo connector (connected to the H.V. Lemo box), then the last three wires connect to the Terminal block. Write down the number where the orange, blue and yellow wires go to on the terminal block and disconnect them with your small screwdriver. Carefully pull the old cable bundle through the cable entrance hole from the pan area. The old cable bundle may now be discarded. 21.Carefully feed (one connector at a time) the new cable bundle wires through the cable entrance hole into the pan area. Connect the wires to their proper locations. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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22.Then move the arm all the way down to the foot end of the scan table. At this time make sure that the Lower cable bundle and the high voltage cable bundle have some slack where the cables enter the cable track near the bulkhead area. Then make sure the cable track has at least 1/8" of clearance from hitting the frame. To adjust this slide the cable track in the trough it rides in to get the proper clearance, then tighten the screw that holds the cable track in place with a 1/8" hex wrench and a 3/8" wrench. Move the arm up and down the scan table to be sure there is nothing wrong with the cable track motion. Leave the arm at the foot end of the table. 23.Leave a little slack in the cables from the cable track to the pan area to allow all of the cables to be routed and wire tied exactly like the original cables. 24.Reconnect the A/C power cord, put the table top, pad, and end panels back on the scanner. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

25.Turn on the scan table, computer, monitor and printer. Perform required tests per section 6.9 of the DPX-NT Service Manual.

5.4 Upper Cable Bundle Replacement Tools Necessary: • Small Phillips Screwdriver • Small Slot Screwdriver • Diagonal Cutters • Hex Wrench Set • Mini Molex Pin Extractor • Large and Small Wire Ties.

5.4.1 Procedure 1. Turn off the power to the scan table. 2. Remove the table top by removing the two screws at each end. 3. Remove the front panel of the scan table 4. Lastly, remove the column cover of the arm held in place by screws. 5. Remove the upper and lower arm covers by removing the (8) screws that hold it in place. 6.Open the cable track and cut the wire ties at the end of it. Disconnect all the cables coming from the cable track and remove the cable bundle as far as the top of the column (through the hole). Page 132 of 141



7.Place the new cable bundle in the cable track and connect all cables to their appropriate positions. Close the cable track and wire tie the cables at the end of it. Route the cable bundle through the hole in the top of the column. 8.Next locate the Laser On light and disconnect it. Remove this cable to the top of the column cutting any necessary wire ties. 9.Route the new cable to the Laser On light and connect. Replace any wire ties removed in step 5. 10.From the back of the arm column follow the cables vertically down and cut all the wire ties holding the upper cable bundle to the other cable assemblies. 11.Carefully pull the upper cable bundle out towards the back of the arm and down through the holes in the column. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

12.Next cut the wire ties that hold the cables down near the bulkhead, these are located in the lower rear portion of the arm. 13.Make sure the bulkhead connectors are labeled on both sides of the bulkhead bracket and then disconnect them. 14.Next remove the two (16) pin Molex housing connectors that are attached to the upper cable assemblies from the bulkhead bracket. Also disconnect the LEMO connector from the bulkhead bracket. Pull the housings and the Signal cable connectors out to work on them. 15.Use the mini Molex pin extractor tool and remove from bulkhead 1 pin16 and pin8. From bulkhead 2 (the lower connector) remove pin15, pin16, pin6, pin7, and pin8. 16.Now remove the old cable bundle by pulling the cable out through the back of the column. The old cable may now be discarded. 17.Next route the new cable bundle through the column wire tieing as you go. 18.Route the taped end of the cable through the hole at the bottom of the column to the bulkhead area (follow the other cables that go to the bulkhead). 19.Carefully remove the masking tape from the cable exposing the mini Molex pins and the Lemo connector. Note the orientation of the existing terminals in the bulkhead connectors and the numeric labels at each hole of the connector. 20.Replace the wires one at a time removing the wires from the old cable and replace them with the wires from the new cable. 21.Insert the connectors into the bulkhead bracket the same way they were removed and fasten the upper cable bundle with wire ties as original. 22.From the wire tie just fastened, the cables going into the arm column must not have any slack in the cables (pull the cables from the column area to remove any slack). Make sure that none of the cables hit any of the moving parts in the narrow area where the cables come from the back of the column out to the bulkhead. DPX-NT/MD+ Service Manual (Rev. 3 - 2010) Page 133 of 141 Approved Document - LU44246ADW_r3.pdf Page 134 of 142

23.Mount the column cover back in place and replace the top and bottom arm covers. Replace the table top, table pad and the head and foot end panels back on to the scanner. 24.Turn on the power to the scan table. Run Required tests as prescribed in section 6.9 of the DPX-NT service manual.

5.5 Tube Head Control Cable Replacement Required Tools:

5.5.1 Procedure 1.Switch off the power to the scanner. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

2. Remove the tabletop, head and foot end panels. At the foot end of the scan table unplug the A/C power plug to the scanner. 3.Move the scan arm to the head end of the table. 4.Take the black tape off the high voltage cable bundle at each end of the sleeving (open any cable track clips that are in the way as in step 8) as well as any wire ties holding the bundle in place. Next, slide the sleeving away from the tube head and remove the tape beneath the sleeving. Note the positions of each cable before removing the tape. The cables must be returned to these positions. 5.Disconnect the military-style connector and the ground wire (if one exists) from the tube head and slide the cable out of the black sleeving toward the cable track. 6.Unplug J3 and J5 on the XORB board. Also, trace the ground wire (if one exists) from the control cable and disconnect it from the power supply. Cut the wire ties holding the control cable to the pan. 7.Pry open the plastic retaining clips that hold the cables into the cable track. These clips pivot at the back of the cable track and can either be removed or left in the open position to remove the cables. The screw located at the end of the cable track near the pan must also be removed. Once this screw is removed the cable track can be lifted out of the channel it rides in and the remaining clips can be opened. Mark the position of the cable track screw on the frame to return the track to its original position. 8.Remove the old control cable. Note the position of all the cables in the cable track. They will need to be returned to the same position during this procedure. If the cables are not returned to their original positions, cable damage will result. Page 134 of 141



9.Feed the new cable, military connector first, through the black sleeving on the high voltage cable bundle starting near the bulkhead. The sleeving can be expanded by pushing two parts of it together to better fit the connector through. 10.Once the cable is through the sleeving, connect it to the tube head and connect the ground wire (see figures 1 and 2). Position the cables next to the high voltage cable bracket as in figure 1. The collimator control cable should come out of the cable bundle between the two high voltage cables toward the back of the scanner. Tape the cables together for several inches with three layers of electrical tape starting as close to the bracket as possible. Continue to spiral the tape around the cables as it was originally and finish by taping three layers for several inches near the bulkhead. Tape the sleeving near the bulkhead as it was originally. Pull the sleeving tight along the bundle and tape near the tube head. Wire tie the cables to the tube head high voltage cable bracket. . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Figure 5-8. Profile Cable Routing Diagram



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Figure 5-9. Top Down Cable Routing Diagram

11.Lay the control cable in the cable track in the same position as the original one. Start replacing wire ties between the bulkhead and the tube head. Before tightening the wire ties assure that there is proper clearance and no stress is applied at any of the connectors or wires through the entire range of motion. Tighten the center cable ties first (two large wire ties put together and located at the center of the high voltage cable trough). Be sure the high voltage cable bundle does not hit the front panel when the tube head is all the way toward the front of the scanner. Make sure the high voltage cables do not hang into the cut out space on the high voltage cable trough. Tighten the three wire ties near the bulkhead. 12.Replace the clips to the cable track and reattach the track to the scanner frame. 13.Move the arm to the foot end of the scan table. Check that the lower cable bundle and the high voltage cable bundle have some slack where the cables enter the cable track near the bulkhead. Check that the cable track has at least 1/8" clearance of the frame. To adjust this, slide the track in its trough, then tighten the screw that holds the track in place. Move the arm up and down the table to verify that the cable track moves properly. 14.Reconnect the A/C power cord, and replace the table top and end panels. 15.Perform required tests as prescribed in section 6.9 of the DPX-NT Service Manual.

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5.6 Tests to Perform after Service Please see LUSE0002 for part specific testing information.

Shutter Cycle Test 1.) Click Tools/Diagnostics/Scanner X-Ray…/ X-Ray Tests tab (default tab). 2.) In the Automatic Test box, ensure Shutter is selected (default), change Number of Passes to 100 and click Start.


3.) If Number of Successes = 100, the result is PASS. If any other result occurs (i.e. error(s)) the result is FAIL. If result is FAIL, the cause of error must be found and cycle test must be rerun until the result is PASS.



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Home Verification Reference DXAP3000 DPX-NT / MD+ Installation Procedure.

Display Panel (LED, E-Stop, positioning switches) Perform the following tests to ensure that the LEDs and positioning and emergency stop switches are operational: 1. Power On (Green) LED Test - Ensure table is plugged in and power switch is switched on. PASS = Power On LED is on. 2. Position Switch Test - Tools/Diagnostics/Scanner Motion. Go to Motion Commands tab, click Enable Joystick. PASS = Switches and motors are operational by pressing switches on front panel to move arm in all directions. 3. X-Ray On (Yellow) Test - Tools/Diagnostics/Scanner X-ray. Click Ramp (in X-ray Source box). PASS = X-Ray On LED is on and the X-Ray Tube Head Fans are ON. 4. Shutter Open (Yellow) Test - Click Open Shutter . PASS = Shutter Open LED is on. 







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5. Laser On (Amber) LED Test - Click Turn On (Laser) . PASS = Laser LED is on. 6. Emergency stop switch Test - Press the Emergency Stop Button. PASS = Laser and all the LED’s (except power) turn off, bell sounds when the shutter closes and X-Ray Source Fans are OFF. 7. Close the window. Check the Error log for errors other than expected E-Stop and Shutter/Scanner Reset Faults. Overall Display Panel Test PASS = All Tests 1-6 = PASS and there are no unexpected errors in log. 





External Options (External E-Stop Switch, External X-Ray Light On) Reference DXAP0012 DPX-Series, Prodigy External Options Installation

Voltage/Continuity Verification . s s e c o r P O C E / R C E e h t o t t c e j b u s e r a s e g n a h . C t . n l e o r m t n u o c o C d e i s g h n t a f h o C s l u a t a t m r s o f e r h e t d e n i n u d m r n t e a e d d e o s t a e m l e e t r s s i y t S n p e o h m s u k c r o o D w - y E M S C A H E E L E G R e : t h e t e a t e S S

Ground Verification 7943 – Verify by visual inspection that the 2 ground cables on one end and the 4 ground cables on the other end are connected. 

1 end to bulkhead (spade connection)



1 end to rear carriage (screw connection)



2 ends to pan near HVPS (nut connection)



2 ends to pan near CSBC (nut connection)

7930 – Verify by visual inspection that the 1 ground cable on each end is connected. 

1 end to bulkhead (spade connection)



1 end to detector carriage (screw connection)

2700 – Verify by visual inspection that the 2 grounds are connected to the pan near the CSBC (nut connection). 41085 – Verify by visual inspection that the 2 grounds are connected to the pan near the CSBC (nut connection). 8204 – Verify by visual inspection that the 1 ground cable on each end is connected. 1 end to tube head (screw connection) 1 end to pan near positive HVPS (nut connection)  

2698 – Verify by visual inspection that the ground is connected to the pan near the centent (nut connection). 8249 – Verify by visual inspection that the 1 ground cable on each end is connected. 1 end to tube head (screw connection) 1 end to pan near HVPS (nut connection)  

40296 – Verify by visual inspection that the ground cable connects the panel to the pan. 1983 – Verify by visual inspection that the ground cable is connected. DPX-NT/MD+ Service Manual (Rev. 3 - 2010)


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Beam Wobble Reference DXAP4009 DPX-NT/Bravo/Duo Beam Wobble Procedure

Alignment Verification (Photo) Reference DXAP3001 DPX-NT / MD+ Source – Detector Alignment Procedure

Secondary Calibration (QA) Reference Section 2.13.2 Starting the Daily QA (secondary calibration) from this manual

Spine Phantom


Reference the enCORE Operator's Manual for the Aluminum Spine Phantom Scanning Procedure. Average the results from the 3 analyzed scans, and verify that the mean is within 2% of the expected value for the phantom.

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MT - Densitometria GE DPX NT

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