ATA 49 APU.pdf

A334−2/3

Auxiliary Power Unit

Lufthansa Technical Training

A334−2/3


49−00 GENERAL 49−10 POWER PLANT 49−12 APU MOUNTS 49−20 ENGINE 49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING Lufthansa Technical Training

49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING 49−73 ANALYZERS 49−40 IGNITION AND STARTING 49−60 ENGINE CONTROLS 49−61 CONTROL AND MONITORING


AUXILIARY POWER UNIT GENERAL

A334-200/300 GTCP 331−350C

49−00

ATA 49

AUXILIARY POWER UNIT

Page 1


A334−2/3


49−00 GENERAL 49−10 POWER PLANT 49−12 APU MOUNTS 49−20 ENGINE 49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR



A334-200/300 GTCP 331−350C

49−00

49−00

GENERAL SUMMARY

APU INTRODUCTION General The APU (Auxiliary Power Unit) designation is Garrett GTCP 331−350C. GTCP is an abbreviation for Gas−Turbine Compressor Power−Unit. Purpose The APU is an independent aircraft system for the alternative power supply of the electric and pneumatic system. S It supplies the A/C (Air/Craft) Electrical System S It supplies the A/C Pneumatic System The primary users are the: − ECS (Environmental Control System) for the airconditioning − MES (Main Engine Start) System − WAI (Wing Anti Ice) System Operation on Ground On ground, the APU permits the aircraft to operate independently from an external supply of pneumatic and electrical power during the ground service and maintenance.

Operation Data Restart in Flight

up to 41,000 ft

Energizing of Electrical Power

up to 41,000 ft

Energizing of Pneumatic Power

up to 23,000 ft

Constant Speed

100% (N=41,730 rpm)

Bleed Load

324 lb/min. (Sea Level, 37.8 °C)

Shaft Load

166 shp (Sea Level, 37.8 °C)

Max. EGT (Exhaust Gas Temperature

660 °C on Speed

Air Pressure

35 psi Normal / 50 psi Maximum

Generator Output

115 Volts / 400 Hz

Weight

250 kg

Operation in Flight During the flight the main engines are the primary power supply for the electrical system and the pneumatic system. The APU serves as a backup power source in case of aircraft system malfunction. Control and Monitoring An ECB (Electronic Control Box) monitors the APU operation and gives full self protection. It is a Full−Authority Electronic Control.

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A334-200/300 GTCP 331−350C

49−00

APU LOAD BLEED VALVE

WING ANTI ICE

AUXILIARY POWER UNIT

ENGINE START APU CHECK VALVE

X-BLEED VALVE

Page 3 Figure 1 APUWiK ECS-Supply Schematic FRA US/E-1 Feb 01, 2008



A334-200/300 GTCP 331−350C

49−00 APU Operating Envelope The starting and operating envelope limiting parameters are governed by the ambient temperature and pressure altitude. The APU has the capability of providing pneumatic and shaft power to satisfy aircraft demands. Combination loading (electrical and pneumatic power) is available up to 23,000 ft. Electrical power which has priority over pneumatic supply is available up to 41,000 ft. APU start operation may be accomplished up to 41,000 ft but starting merely with APU battery is limited to 25,000 ft. On aircraft equipped with a TRU (Transformer Rectifier Unit) starts may be attempted up to 41,000 ft.

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A334-200/300 GTCP 331−350C

49−00 APU RESTART AND OPERATION LIMIT NORMAL AC POWER SUPPLY PRESSURE ALTITUDE

(1000 FT) 41

40 SHAFT POWER ONLY

38

APU BATTERY START LIMIT

25 22.5

14,6

10

ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ

BLEED AIR AND SHAFT POWER

16,6

GROUND STARTING AND OPERATION LIMIT

0 1

60 74

40 54

20

0

30 21.5 AMBIENT AIR TEMPERATURE DEG.C

20 17

40 22

55

ISA = INTERNATIONAL STANDART ATMOSPHERE

Page 5 Figure 2 APUWiK Operating Envelope FRA US/E-1 Feb 01, 2008



A334-200/300 GTCP 331−350C

49−00 APU CONTROLS General Normal control of the APU is carried out from the APU Control Panel 215VU located in the cockpit. The APU has an emergency shutdown−circuit which will stop the APU automatically on ground if the APU fire and overheat detection system finds an overheat in the APU compartment. During the flight you must push the APU SQUIB DISCH P/BSW on the Fire Panel 231VU to operate the fire extinguishing system. However, a manual initiated emergency shutdown may performed on ground from outside of the aircraft at the following loations: S External Power Control Panel 925VU S Refuel/Defuel Panel 990VU

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A334-200/300 GTCP 331−350C

49−00

231VU APU

AGENT

TEST

APU

MASTER SW

SQUIB

FAULT ON/R

DISCH

START

APU FIRE PANEL

AVAIL ON

990VU 925VU APU EMERG.

COCKPIT CALL

AVNCS

COCKPIT CALL

NLG LIGHT

VENT

SVCE INT SHUT DOWN

REFUEL/DEFUEL PANEL

APU

FIRE

APU

SHUT OFF

ADIRU

HORN

RESET

LIGHT TEST

EXTERNAL POWER CONTROL PANEL

Page 7 Figure 3 APUWiK Controls FRA US/E-1 Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT POWER PLANT

A334-200/300 GTCP 331−350C

49−10

49−10

POWER PLANT

APU PRESENTATION General The Auxiliary Power Unit [5100KB] is installed in the APU compartment in the aircraft tailcone. Access to the APU compartment is gained through the two access doors 315AL and 316AR. The APU compartment has a forward firewall at FR95 and a rear firewall at FR101. An APU fire and overheat detection system and an APU fire−extinguishing system protect the APU and the APU compartment in case of a fire. The fire extinguisher bottle is installed on the front face of the forward firewall of the APU compartment (FR95). Also installed in the tailcone are the air intake system, the APU mounting system, the exhaust system and the power plant drain−system. A drainmast is installed in the left access door 315AL. A louvered overpressure release−door is installed in the structure on the top left side of the APU compartment.

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A334-200/300 GTCP 331−350C

49−10

APU ACCESS DOORS

FR101

APU DRAIN LINES

ACCESS DOOR 316 AR

COMPARTMENT DRAIN MAST

FR95 ACCESS DOOR 315 AL

Page 9

AIR INTAKE

Figure 4 APUWiK Installation and Access FRA US/E-1 Feb 01, 2008



A334-200/300 GTCP 331−350C

49−10 Identification Plate The Identification Plate indicates the APU modification status after the last shop maintenance. It contains the P/N (Part/Number), the Model- and the Series number, the Change Number and some performance data of the APU. It is located on the left side at the air plenum chamber. NOTE:

Within the AMM (Aircraft Maintenance Manual) there are some tasks, which are in relation to different APU modification status. The different procedures within a task are identified by the P/N, the Series Number and Change Number.

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A334-200/300 GTCP 331−350C

49−10

PN 3800454−4 99193 MODEL GTCP331−350[C] SERNO R−248 SERIES 47 INSP DATE FUEL(SEE MODEL SPEC) MAX 41,730 RPM RATED DSGN ACT

SPEED44,651RPM ALLOWED

MAX 1196 647

MAX

F RATED 1215 657

C RATED

MAX DRY WEIGHT 542.3 IBS MFR C0548 C77A CAT I TS JAR

SERVICE CAT ESSENTIAL LUBE (SEE MODEL SPEC) SL RATED 166SHP. 324LBS/MIN OUTPUT 50.3PSIA AT 100 F DAY F ALLOWED

C ALLOWED

SPECIAL MARKINGS MOD RECORD /63 ENGINE,GAS TURBINE GARRETT GMBH RAUNHEIM, GRMANY

Page 11 Figure 5 Identification Plate FRA US/E-1 WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT APU MOUNTS

A334-200/300 GTCP 331−350C

49−12

49−12

APU MOUNTS

SYSTEM PRESENTATION The APU has a three−point Mounting System. Seven Rod Assemblies make the connection between the three APU Mount Brackets and the top structure of the APU compartment. Three Vibration Isolators are installed between the Rod Assemblies and the APU Mount Brackets. They prevent the two−way transmission of vibrations and shocks between the APU and the structure in all directions. The mounting system of the APU has the subsequent primary components: S Structure Brackets (7ea.) S Rod Assemblies (7 ea.) S APU Mounting Brackets (3 ea.) S Vibration Isolators (3 ea.)

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AUXILIARY POWER UNIT APU MOUNTS

A334-200/300 GTCP 331−350C

49−12

AFT MOUNT

FWD RIGHT MOUNT

FWD LEFT MOUNT

ROD ASSEMBLY

MOUNT BRACKET VIBRATION ISOLATOR

Page 13 Figure 6 APUWiK Mounts FRA US/E-1 Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT ENGINE

A334-200/300 GTCP 331−350C

49−20

49−20

ENGINE

GENERAL LAYOUT Engine Modules The engine is the primary component of the APU, it consists of three main modules: S Power Section S Load Compressor S Accessory Drive Gearbox The LRUs (Line Replaceable Units) of the APU are installed on the engine. You can remove or install them easily.

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A334-200/300 GTCP 331−350C

49−20

ACCESSORY LOAD DRIVE GEARBOX COMPRESSOR

POWER SECTION

ENGINE

Page 15 Figure 7 Engine Modules FRA US/E-1 WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−20 DESCRIPTION CONSTRUCTION The APU is constructed as a modular design and consists of the following three Major Modules: S Power Section which is subdivided into − Compressor Section and − Turbine Section S Load Compressor S Accessory Gear-Box (AGB) POWER SECTION Compressor The Compressor is a sub−module which can be removed at shop maintenance level and is of a two stage centrifugal compressor design. The main components of the compressor are the: S 1st Stage Impeller and Diffuser S 2nd stage Impeller and Diffuser Combustion Chamber The combustion chamber is of a reverse flow annular design and fits inside the turbine plenum. The main parts of the combustion chamber are the: S Combustion Chamber Liner S Outer Combustion Chamber Case The following components are installed on the combustion chamber: − Igniter Plugs − Fuel Nozzles − Combustion Chamber Drain Valve Turbine The turbine is of a three stage axial design and can be removed at shop maintenance level. It drives the compressor, the load compressor and the geartrain of the accessory gearbox. The turbine first stage vanes and blades are air cooled by compressor discharged air.

LOAD COMPRESSOR The load compressor is of a single centrifugal stage design. The main components of the load compressor are the: S Inlet Guide Vane Assembly S Impeller S Collector Scroll S Acoustic Material Inlet Guide Vanes The IGV (Inlet Guide Vane) Assembly controls the airflow through the load compressor. The 24 Inlet Guide Vanes are moved simultaneously by a geartrain operated by an actuator. The Inlet Guide Vane actuator is operated by high pressure fuel supplied from the Fuel Control Unit. The Inlet Guide Vane opening angle depends on the bleed air demand for the: − MES (Main Engine Start) System and, − ECS (Environmental Control System) ACCESSORY GEARBOX The AGB (Accessory Gear-Box) is directly connected to the Load Compressor Module which transmits the shaft power from the power section. The gearbox transmits the shaft power to the APU accessories and to the APU generator which are installed on the gearbox pads. The gearbox is also the oil reservoir for the APU oil system and provides attachment for the two forward APU Mounting Brackets. The major components mounted on the AGB are the: S Electrical Generator S Starter and Starter Clutch Assembly S Compartment Cooling Fan S Oil Pump Module which drives the Fuel Control Unit S Gravity Oil Fill Port and Oil Level Sight Glass

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A334-200/300 GTCP 331−350C

49−20

LOAD COMPRESSOR IMPELLER

SCROLL COMPRESSOR AIR COLLECTOR

1st STAGE IMPELLER

2nd STAGE IMPELLER 1st STAGE TURBINE 2st STAGE TURBINE

3rd STAGE TURBINE

INLET GUIDE VANES

COMPRESSOR SECTION GEAR BOX

LOAD COMPRESSOR MODULE

ANNULAR COMBUSTOR

TURBINE SECTION

POWER SECTION

Page 17 Figure 8 GTCP 331−350 Engine X-Section FRA US/E-1 WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−20

Page 18 Figure 9 GTCP 331−350 Engine Cutaway FRA US/E-1 WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−20

A VIEW-A

COOLING FAN ATTACHMENT FLANGE STARTER MOTOR PAD

GENERATOR ATTACHMENT FLANGE

OIL PUMP/FUEL CONTROL PAD

Page 19 Figure 10 FRA US/E-1

AGB Mounting Pads WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT EXHAUST

A334-200/300 GTCP 331−350C

49−80

49−80

EXHAUST

DESCRIPTION Purpose The exhaust system releases the APU exhaust gas to the ambient air. The exhaust gas contains the combustion gases and the load compressor surge−air. The exhaust system also decreases the exhaust noise level, most of the noise comes from the outlet of the APU exhaust diffuser (the flange of the turbine heat shield). Installation The system is installed in the exhaust muffler compartment together with the rear access fairing. The exhaust muffler goes through the rear firewall of the APU compartment. It has a thermal insulation to protect the structure of the exhaust muffler−compartment and the rear access fairing. The exhaust coupling makes a flexible connection to the turbine heat shield and the exhaust muffler. Construction A firewall seal seals the space between the exhaust and the rear firewall. Access To get access to the exhaust system, you can open the rear access fairing 317AL and the APU access doors 315AL and 316AR.

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AUXILIARY POWER UNIT EXHAUST

A334-200/300 GTCP 331−350C

49−80

EXHAUST MUFFLER

INSULATION

FIRE WALL SEAL EXHAUST COUPLING REAR PART OF THE TURBINE HEAT SHIELD


Engine Exhaust WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT POWER PLANT DRAIN SYSTEM

A334-200/300 GTCP 331−350C

49−17

49−17

POWER PLANT DRAIN SYSTEM

DRAIN SYSTEM DESCRIPTION General The APU drain−system removes excess fluids from the APU and the APU Exhaust Muffler to the external air. Thus it prevents that excess fluids can collect on or in the power plant and cause a fire hazard. A Drain Mast is installed in the left access door of the APU compartment. Any excess fluids which could occur in the APU compartment, flow out of the drainmast to the atmosphere. The APU drain system is divided in the following two sub−systems: S Engine Drain System S Accessory Drain System Engine Drain System Following components are connected to the APU Engine Drain System: S Combustion Chamber S APU Exhaust Cone S Exhaust Muffler Accessory Drain Following components are connected to the APU Accessory Drain System: S Inlet Guide Vane Actuator S Surge Control Valve Actuator S Fuel Control Unit/Oil Pump Module

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A334-200/300 GTCP 331−350C

49−17

APU PLUMBING

ACCESSORIES INLET GUIDE VANE ACTUATOR

SURGE CONTROL VALVE ACTUATOR

AIRCRAFT DRAIN LINES

ENGINE FUEL CONTR. UNIT/OIL PUMP MODULE DRAIN PORT AIR CHECK VALVE

COMBUSTION CHAMBER

APU EXHAUST CONE

EXHAUST MUFFLER

FR101 REAR FIREWALL

COMBUSTION CHAMBER DRAIN VALVE

ENGINE DRAIN LINE

ACCESSORY DRAIN LINE

FWD FIREWALL

FUSELAGE/TAIL CONE

FR95


FR102

DRAIN MAST ON APU ACCESS DOOR 315AL

APU DrainFeb System WiK 01, 2008



A334-200/300 GTCP 331−350C

49−17 Combustion Chamber Drain Valve The Combustion Chamber Drain Valve is a control valve which is of the ball valve type. When the APU does not operate, the valve is spring loaded open (Air Pressure <5 psi) and collected fluids may be drained to overboard. When APU is running the valve is hold in closed position by combustion chamber pressure (>10 psi).

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A334-200/300 GTCP 331−350C

49−17

TUBES

DRAINS

1/4

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A334-200/300 GTCP 331−350C

49−17 EXHAUST CONE DRAIN PORT

TUBES


DRAINS

EXHAUST MUFFLER DRAIN LINE FROM THE APU - SCV ACTUATOR - IGV ACTUATOR - FUEL CONTROL UNIT - OIL PUMP MODULE - CAVITY DRAIN

ENGINE DRAIN LINE ACCESSORY DRAIN LINE

2/4

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A334-200/300 GTCP 331−350C


TUBES


DRAINS



COMBUSTION CHAMBER DRAIN VALVE SECTION

C-C

C

3/4 NORMALLY OPEN

AIR PRESSURE CLOSED

C

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A334-200/300 GTCP 331−350C


TUBES


DRAINS



COMBUSTION CHAMBER DRAIN VALVE SECTION

C-C

C 315AL

316AR 4/4 NORMALLY OPEN

AIR PRESSURE CLOSED


APU DrainFeb Lines WiK 01, 2008

C

ATTENTION: APU Leak Rates are described in the AMM 49−00−00−710−801

COMPARTMENT DRAIN MAST


A334−2/3




AUXILIARY POWER UNIT AIR INTAKE SYSTEM

A334-200/300 GTCP 331−350C

49−16

49−16

AIR INTAKE SYSTEM

AIR INTAKE SYSTEM DESCRIPTION General The Air Intake System supplies ambient air to the inlet plenum chamber of the APU. The location of the air intake prevents ingestion of the APU exhaust gases through the APU. The air intake system consists of the subsequent components: S Air Intake S Air Intake Diverter S Air Intake Flap S Air Intake Flap Actuator [516KB] S Air Intake Duct The Air Intake Diverter and the Air Intake are installed in the lower section of the fuselage in front of the forward firewall of the APU compartment (FR95). The air flows through the Air Intake Duct from the Air intake to the Inlet Plenum Chamber of the APU. The Air Intake has an Air Intake Flap which is in the closed position when the APU does not operate. The Air Intake Flap Actuator moves the Air Intake Flap to the appropriate position. The flap actuator receives the command signals from the ECB 59KD and sends the flap position signals back to the ECB. Air Intake Diverter The Diverter Case which has an elliptic shape is riveted to the fuselage forward of the air intake. The Diverter Plate is installed with screws onto the Diverter case. The Air Intake diverter has two main tasks: During the flight, the Diverter increases the ram air recovery as it diverts the low energy part of the boundary layer. On the ground and in the flight, the diverter (in conjunction with the fluid gutters) prevents fluids flowing along the fuselage from entering the Air Intake.

Air Intake Flap The Air Intake Flap is operated by the Air Inlet Flap Actuator and closes or opens the Air Intake. The Flap opens prior APU starting and is closed when the APU does not operate. Air Intake Flap Actuator The Air Intake Flap Actuator moves the air Intake and holds it in the open or closed position. The Actuator is controlled and monitored by the ECB (Electronic Control Box). It is possible to manual override the Air Intake Flap Actuator in open or closed position by a Manual Drive Shaft, as described in the AMM (Aircraft Maintenance Manual). Air Intake Duct The air intake duct is made as an aerodynamically shaped resonator−type muffler. The purpose is to decrease the noise which is caused by the airflow through it. Adjustable tie−rods hold the air intake duct in the correct position. Indication The Flap open position is indicated on the APU System Display by a green FLAP OPEN message. In all other cases there is no indication shown.

FLAP OPEN 5 7 11

EGT °C

3 600

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A334-200/300 GTCP 331−350C

49−16 AIR INTAKE FLAP ACTUATOR [516KB]

COMP

ACTUATOR MANUAL DRIVE

AIR INTAKE

AIR INTAKE DUCT

AIR INTAKE DIVERTER

(APPROX. 34 KG)

AIR INTAKE FLAP DIVERTER CASE AIR INTAKE FLAP & ACTUATOR

DIVERTER PLATE


AirWiK Intake Feb System 01, 2008



A334-200/300 GTCP 331−350C

49−16 AIR INTAKE SYSTEM OPERATION General The Intake Flap Actuator is a 28 VDC Linear Actuator with a Thermal Overload Switch and integrated Brake. The ECB 59KD supplies the necessary electrical power for the operation to the air intake flap−actuator 516KB. The two limit switches and the two position switches control the position of the air intake flap−actuator. Operation FLAP OPEN COMMAND When you push the MASTER SW P/BSW 14KD to the on position on the overhead panel 215VU, the ECB [59KD] is energized and supplies 28 VDC electrical power to the DC motor of the flap actuator which operates and moves the air intake flap to the open position. The ECB receives the following signals from the actuator: S Air Intake Flap Open S Air Intake Flap Closed S Air Intake Flap Movement FLAP CLOSE COMMAND The ECB controls the air intake flap actuator to extend (close the flap) when: S the APU did not operate and you push the APU MASTER SW P/BSW 14KD on the overhead panel 215VU to the reset position S the APU speed N decreases to less than 7 % during the APU shutdown sequence S an APU auto shutdown sequence or an APU emergency shutdown is initiated by the ECB S An ASD (Auto Shut Down) is caused with running APU (N > 7%) and Inlet Flap not fully open.

Indicating S FLAP OPEN is indicated in green lettering on the ECAM (Electronic Centralized Aircraft Monitoring) APU System Display when the ECB receives a 28 VDC “FLAP OPEN“ signal from the retracted position switch on the flap actuator. S When the ECB receives a “FLAP NOT OPEN“ ground signal from the Retracted Position Switch on the flap actuator, it transmits no flap signal to the EIS. In this case there is no flap position indication on the APU system page. S When the ECB finds a flap actuator fault during the APU start sequence, it starts the APU ASD (Auto Shut-Down) sequence and you will get the subsequent indications in the cockpit. S On the APU MASTER SW P/BSW 14KD on the overhead panel 215VU the amber FAULT light comes on S On the APU START P/BSW 2KA on the overhead panel 215VU the blue ON light goes off. − On the master caution P/BSW’s on the glareshield panels 411VU and 412VU the amber MASTER CAUT indications come on − A single chime is heard − On the EIS Engine/Warning Display (EWD): S APU FAULT S AUTO SHUT DOWN S MASTER SW ..........OFF − On the EIS System Display (SD): S STATUS S INOP SYS S APU Flap Actuator Fault The ECB generates this fault: − the travel time is: t > 29sec − the actuator has a open/short circuit.

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A334-200/300 GTCP 331−350C

49−16

SHUTDOWN APU MASTER

PUT COMPLETE

FAULT

UNSD

UNSD

SWITCH

FLAP OPEN COMMAND CLOSE

14KD

M

BRAKE

30s

ON/R APU

OVHT SW

MASTER SW

M

OFF

OPEN

N 7 FLAP CLOSE COMMAND

215VU

309PP

UNSD UNSD

30s SHUTDOWN

28VDC 28VDC 1KD

2KD 4KD

APU MAIN

28VDC

RELAY

5000VE

AIR INTAKE FLAP ACTUATOR 516KB

LABEL 37 FLAP OPEN SIGNAL

FLAP CLOSE COMPLETE

BIT 15 FLAP OPEN

FLAP OPEN/CLOSE SIGNAL LOGIC

FLAP MOVE SIGNAL

FLAP CLOSE SIGNAL

LABEL 37 FLAP OPEN COMPLETE

SYSTEM DISPLAY 300VU (ALL POSSIBLE INDICATIONS SHOWN)

BIT 14 ECB 59KD


AirWiK Intake Feb Flap01,Control 2008


A334−2/3




AUXILIARY POWER UNIT OIL

A334-200/300 GTCP 331−350C

49−90

49−90

OIL

INTRODUCTION Purpose The self contained oil system lubricates, cleans and cools the APU bearings and accessory gearbox. The oil system is monitored by the ECB (Electronic Control Box) which receives temperature, pressure and quantity signals. To help cold starting, a de−oiling valve is mounted on the oil pump inlet. The oil is also used to cool and lubricate the gearbox mounted Generator as well as the Starter Motor Clutch. An air Oil Cooler in conjunction with a cooling fan is used to cool the APU oil and to ventilate the APU compartment.

Page 30


AUXILIARY POWER UNIT OIL

A334-200/300 GTCP 331−350C

49−90

ACCESSORY GEARBOX

OIL COOLER

ENGINE BEARINGS

GENERATOR

STARTER CLUTCH

DE-OILING VALVE LUBRICATION MODULE TEMPERATURE PRESSURE QUANTITY

ELECTRONIC CONTROL BOX Page 31 Figure 16

Oil System Design


COMP

AUXILIARY POWER UNIT OIL SYSTEM

A334-200/300 GTCP 331−350C

49−90 SYSTEM DESCRIPTION Purpose The oil system supplies the oil which lubricates and cools the APU and the APU generator. General The oil system has the following subsystems: S Storage and Distribution System S Oil Indicating System S Low Oil Pressure and High Oil−Temperature Warning System S Oil Heating System Storage and Distribution The oil is stored in the lower part of the gearbox (approximately 7.5 liters). For gravity oil tank servicing, there is a filler cap and a sight glass attached on the gearbox. A fill and overflow port provides for oil pressure filling. An Oil Pump Module is mounted onto the AGB (Accessory Gear-Box) in order to supply the bearings and gears with oil and return it back into the gearbox. Filtered, temperature and pressure regulated oil is supplied to: S the Engine S the APU Generator The system has: S an Integral Oil Reservoir with an Electrical Chip Detector and a Low Oil Temperature Sensor S an Oil Pump Module with Oil Filters S an Oil cooler The APU has three oil sumps: S the Gearbox Sump S the Mid Sump S the Aft Sump The Gearbox Sump is a wet sump which is also the Integral Oil Reservoir. The Mid Sump and the Aft Sump are scavenged sumps. The three sumps have no direct connection between each other.

Oil Indicating System The oil indicating system indicates if the oil level in the integral oil reservoir is not sufficient or if an oil servicing is necessary. When the APU does not run, the ECB monitors the status of the Low Oil Quantity (LOQ) switch. LOP and HOT Warning System The LOP (Low Oil Pressure) and HOT (High Oil Temperature) Warning System together with the ECB monitor the APU oil pressure and the oil temperature. They also monitor the temperature of the APU generator scavenge oil. The system protects the APU against low oil pressure and high oil temperature. When the ECB receives the low oil pressure or a high oil temperature signal, it starts the APU automatic shutdown sequence (if it is not inhibited). Oil Heating System An APU oil heater is attached to the lower accessory gearbox. The APU oil heater increases the temperature of the oil in the APU gearbox oil reservoir when the APU is not in operation and the oil temperature is too low.

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AUXILIARY POWER UNIT OIL SYSTEM

A334-200/300 GTCP 331−350C

49−90

ACCESSORY GEARBOX

ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ

COMP

OIL COOLER

GEN

GEN TEMP SENSOR

GEARS

GEN OIL FILTER

SCAVENGE REGULATED PRESSURE PUMP INLET RETURN

LOP

HOT

FWD SUMP

STARTER

AFT SUMP

SCV OIL FILTER

OIL HEATER

LOT SNSR

OIL QTY CHIP DET

ELECTRONIC CONTROL BOX

OIL PUMP MODULE

S

DE-OILING SOL-VALVE


OilWiK SystemFeb Schematic 01, 2008


A334−2/3




AUXILIARY POWER UNIT OIL STORAGE AND DISTRIBUTION

A334-200/300 GTCP 331−350C

49−91

49−91

OIL STORAGE AND DISTRIBUTION

STORAGE SYSTEM DESCRIPTION General The lower part of the Accessory Drive Gearbox is the Integral Oil Reservoir of the APU. The subsequent components are installed onto the Accessory Drive Gearbox: S Gravity Fill Port and a Pressure Fill Port S Oil Level Sight Glass S Oil Quantity Transmitter S Low Oil Quantity Switch S Low Oil Temperature Sensor S Electrical Chip Detector with Drain Plug S Oil Heater S Air/Oil Separator Gravity and Pressure Fill Port The Gravity Fill Port and Pressure Fill Port are provisions for APU oil servicing. The sight glass is used for visual oil level check. Oil Quantity Transmitter The Oil Quantity Transmitter supplies an electrical signal to the ECB concerning oil level status. This information is indicated on the APU System Display when the APU is stopped and the aircraft is on ground.

Electrical Chip Detector The Electrical Chip Detector is is mounted at the lowest point on the gearbox. It is of the magnetic type. The chip detector collects magnetically the metallic particles from the oil sump, the electrical contact gap of the Chip Detector is open until sufficient quantity of particles is accumulated to close the gap and provide a signal to ECB. The chip detector is monitored during IOT. When the Chip Detector is faulty, it will be stored as a CLASS-2 fault with a CMS message OIL CHIP DETECTION. NOTE:

Oil Chip Detection may lead to an APU Auto Shutdown. Refer to the TSM (Trouble Shooting Manual).

Oil Heater An Oil Heater is used to warm up the reservoir oil during cold soak conditions. The Heater heats up the oil in the gearbox to a temperature of approximately 43 °C when the APU Master Switch is off. Air/Oil Separator The oil reservoir has a connection to the ambient air through an air/oil separator. The air/oil separator is connected through a gearbox vent line to the APU exhaust cone.

Low Oil Temperature Sensor The Low Oil Temperature Sensor measures the temperature of the oil in the reservoir. The ECB uses this signal for reducing the load of the Oil Pump Module and Starter, by energizing the normally closed De-Oil Solenoid Valve during cold oil conditions. In this case oil from the oil pump outlet returns to the pump inlet and mixes with the inlet oil, thus the pump outlet is de−pressurized.

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A334-200/300 GTCP 331−350C

49−91

AIR/OIL SEPARATOR PORT

LOW OIL TEMPERATURE SENSOR

OIL HEATER

LOW OIL QUANTITY SWITCH

ELECTRICAL CHIP DETECTOR AND DRAIN PLUG


OilWiK SystemFeb Component Location (1/2) 01, 2008



A334-200/300 GTCP 331−350C

49−91 DISTRIBUTION SYSTEM DESCRIPTION General The subsequent components make the oil distribution system: S Oil Pump Module S The Oil Cooler S Oil Filters Oil Pump Module The Oil Pump Module removes the oil from the oil reservoir by suction. It regulates the oil pressure and supplies the temperature regulated and filtered oil to the lubrication points of the: S Engine S Load compressor S Accessory Drive Gearbox S APU Generator The Oil Pump Module removes the oil by suction (the scavenged oil) from the: S Mid Sump S Aft Sump S APU Generator During cold weather starting conditions, the ECB will automatically open the De-Oiling Solenoid Valve to reduce starter motor and lube pump load caused by cold oil. The scavenged oil from the Mid Sump and the Aft Sump is returned to the oil reservoir. The generator scavenge oil is supplied to the Starter Clutch Sprags. The oil which lubricates the gears and bearings of the gearbox, is returned to the reservoir by gravity.

Oil Filters The distribution system has two oil filters: S Lubrication Oil Filter S Generator Scavenge Oil Filter The filters remove unwanted materials from the oil. The Lubrication Oil Filter cleans all the lubrication oil before it is supplied to the lubrication points. The Generator Scavenge Oil Filter cleans unwanted materials from the generator scavenge oil. This makes sure that no contaminated oil returns from the Generator to the oil reservoir and the Starter Clutch Sprags are lubricated during the APU shutdown. Distribution System Monitoring The ECB monitors the lubrication oil temperature and pressure. A High−Oil Temperature Sensor measures the temperature of the oil and transmits an analog signal to the ECB. If the oil temperature is too high, the ECB starts an APU automatic shutdown (if it is not inhibited). A Low−Oil Pressure Switch monitors the regulated oil pressure. When the Low Oil−Pressure Switch finds that the oil pressure is too low, it transmits a discrete signal to the ECB which will perform an APU automatic shutdown (if it is not inhibited. A Generator Oil−Temperature Sensor is installed on the APU generator. It measures the oil temperature at the generator oil outlet and transmits it to the ECB. When the generator return oil is too hot, it starts an APU automatic shutdown (if it is not inhibited).

Oil Cooler The Oil Cooler is mounted on the left air inlet plenum. It is an Oil/Air Heat Exchanger which receives the cooling air from the Cooling Fan (Ref.49−52) to decrease the temperature of the oil. A thermal bypass valve installed at the oil cooler inlet prevents cold oil from passing the Heat Exchanger or bypasses oil When the Oil Cooler is blocked.

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A334-200/300 GTCP 331−350C

49−91

LOP/HOT

FILTER

HIGH OIL TEMPERATURE SENSOR LOW OIL PRESSURE SWITCH

OIL COOLER

GENERATOR SCAVENGE OIL FILTER LUBRICATION OIL FILTER

GRAVITY FILL PORT


OilWiK SystemFeb Component Location (2/2) 01, 2008



A334-200/300 GTCP 331−350C

49−91 OIL SERVICING Precautions WARNING:

USE THE CORRECT PERSONAL PROTECTION. OIL CAN HAVE AN ADDITIVE CALLED TRICRESYL PHOSPHATE IN IT. THIS CHEMICAL IS AN ASPHYXIANT, IT IS POISONOUS AND CAN BE ABSORBED THROUGH THE SKIN. ALSO HOT OIL CAN POSSIBLY CAUSE BAD BURNS.

General Reservoir oil servicing is possible by gravity fill or with a pressure fill device. On the left side of the gearbox the subsequent ports are installed: S Gravity Fill Port S Pressure Fill Port S Pressure Fill Overflow Port The gravity fill port has an oil sight glass and an oil scupper. The scupper prevents that oil flows on to the APU and into the APU compartment during the gravity oil fill.

Policy You can read the oil level on the Oil Sight Glass. It must be between the FULL and the ADD mark. The oil quantity at the FULL mark is 7.3 l, at the ADD mark 4.1 l. The difference between the two marks is 3.2 l. NOTE:

The maximum allowable oil consumption is 9.5 cc/hr for a new APU. You can also fill the oil reservoir with a pressure fill device through the pressure fill port. The oil which is more than the FULL mark limit flows through the overflow port back to the reservoir of the fill device. The oil drain plug is installed at the lowest point of the integral oil reservoir. The electrical chip detector is installed in the drain plug. You can remove the drain plug with the chip detector installed. You can also remove the chip detector without the drain plug. The drain plug has a check valve which closes when you remove the chip detector. Thus it is not necessary to drain the oil reservoir for a visual check of the chip detector. Indicating When the oil quantity decreased to 4.1 l or less, the Low Oil Quantity Switch transmits a signal to the ECB. If the APU is stopped and the aircraft is on the ground, the APU system page of the EIS (Electronic Instrument System) shows the LOW OIL LEVEL advisory message in pulsing green. If the oil quantity is more than the set minimum, nothing is shown on the display.

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A334-200/300 GTCP 331−350C

49−91 Quarts

Liters

ADDED OIL (COMMUTATIVE)

GRAPH-B

GRAVITY FILL PORT

Oil quantity in the APU oil reservoir is not sufficient for 14 hours APU operation

Oil Quantity in the APU oil reservoir is sufficient for 14 hours APU if serviced before flight to the FULL MARK on the oil sight glass

GRAPH-A

PRESSURE FILL OVERFLOW PORT

Oil Quantity in the APU oil reservoir is sufficient for minimum 14 hours APU operation without preflight service if no LOW OIL LEVEL Indication is shown

SIGHT GLASS

APU OPERATING TIME (HOURS) CAUTION: OIL PRESSURE FILL PORT

NOTE:

OIL CONSUMPTION IS THE TERM USED FOR THE INTERNAL LOSS OF OIL FROM BEARING SEALS AND AIR/OIL SEPARATOR DURING APU OPERATION. EXTERNAL LEAKS ARE NOT PERMITTED. YOU MUST CORRECT EXTERNAL LEAKS AND CLEAN THE APU, APU COMPARTMENT AND APU AIR INTAKE IMMEDIATELY IF CONTAMINATED. IF THE OIL CONSUMPTION IS HIGHER THAN THE GRAPH-A LIMIT, OR THERE IS A SUDDEN INCREASE, YOU MUST DO THE OIL CONSUMPTION MONITORING VERY CAREFULLY TO PREVENT BAD APU DAMAGE. The added oil (vertical scale) is the total quantity of oil which was added to the oil reservoir in order to compensate for the APU consumption during an operating time period (horizontal scale).


Reservoir Oil Servicing WiK Feb 01, 2008


AUXILIARY POWER UNIT STORAGE AND DISTRIBUTION

A334-200/300 GTCP 331−350C

49−91 COMPONENT DESCRIPTION OIL PUMP MODULE General The Oil Pump Module is mounted on the front side of the accessory drive gear box and driven by the AGB. The module consists of: S Three Lubrication Elements S Two Generator Scavenge Elements S One Aft Sump Scavenge Element S One Mid Sump Scavenge Element S Pressure Relief Valve S Pressure Regulator Valve S De−Oiling Solenoid Valve S Lubrication Filter S Generator Scavenge Filter Lubrication & Scavenge Elements The 3 lubrication elements are identical and work in parallel. Thus it is not necessary to pressurize the gearbox at high altitudes to make sure that the supply of lubrication oil is sufficient. The 2 generator scavenge elements are identical and work in parallel. Thus the oil which lubricates and cools the APU generator is scavenged accurately. The aft sump scavenge−element and the mid sump scavenge−element supply the scavenged oil directly to the oil reservoir. Oil Pressure Relief & Pressure Regulating Valve The Oil Pressure Relief Valve is of the poppet and seat type. It is installed in parallel to the lubrication items and opens at a pressure difference of 200 psi. The Oil Pressure Regulating Valve is of the spool and sleeve type. It is installed in parallel to the lubrication elements and controls the oil pressure to 65 ±5 psi.

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A334-200/300 GTCP 331−350C

49−91

N < 65% ALTITUDE > 31,000 ft APU START OIL TEMP < -6.7°C N < 60% APU ROLLDOWN

ECB 59KD

ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÏÏÏÏÏ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÏÏÏÏÏ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÏÏÏÏÏ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÏÏÏÏÏ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ

COOLING FAN

HIGH OIL TEMPERATURE

GEN OIL TEMP SENSOR

GEN

COOLING FAN

OIL COOLER & THERMAL BYPASS VALVE

GEN HIGH OIL TEMPERATURE

HIGH SPEED PINION

OIL CHIP DETECTION

GEN SPLINE SHAFT

LUBRICATION OIL FILTER

LOW OIL PRESS SW [59KT14]

LOW OIL PRESS S/D LOP SW N > 95% LOT > -4°C

LOW OIL QUANTITY

FWD LOAD COMP HOLD

HIGH OIL TEMP SNSR [59KT11]

GEN GEAR

STARTER CLUTCH GEARS

STARTER SPRAG CLUTCH

OIL RESERVOIR

GENERATOR SCAVENGE-OIL FILTER

MID SUMP

AFT SUMP

OIL PUMP MODULE

AIR/OIL SEPARATOR

LOW OIL LOW OIL OIL HEATER TMP SNSR QTY SW [59KT16] [59KT9] [59KT8] SW

ELEC CHIP DET [59KT5]

1KT

S

DE-OILING SOLENOID VALVE

[4KD]

PUMP INLET

REGULATED PRESSURE

SCAVENGE

RETURN


OilWiK SystemFeb Schematic 01, 2008



A334-200/300 GTCP 331−350C

49−91 Oil Filters Both, the Lubrication Oil Filter and the Generator Scavenge Oil Filter are equipped with a magnetic type differential pressure indicator. It gives you a visual indication when the filter element is clogged. When the pressure difference across the element is 33 ±5 psi a red indicator extends out of the indicator housing. It is magnetically locked out and remains in this position even when the oil pressure decreases at APU shutdown. To reset the indicator pin you push it manually into the housing. A thermal lockout device stops the clogging indicator operation until the oil temperature is more than 37.7 °C. This avoids an irregular clogging indication caused by the higher viscosity of cold oil. The Lubrication Oil Filter has a Filter Bypass Valve which opens when the filter element is fully clogged. Then the oil does not flow through the filter element, but the APU receives lubrication oil further on. The Generator Scavenge Oil Filter has a Pressure Relief Valve which opens when the filter element is fully clogged. The generator scavenge oil then flows to the oil cooler inlet line. Thus the generator scavenge oil is cooled and then cleaned by the Lubrication Oil Filter.

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A334-200/300 GTCP 331−350C

49−91

MODULE

CLOGGING

GEARBOX DRIVE FCU DRIVE

OIL PRESSURE RELIEF VALVE

OIL PRESSURE REGULATOR VALVE LUBE OIL FILTER BYPASS VALVE DE-OILING SOLENOID VALVE

Page 43

FILTER CLEAR

Figure 22 FRA US/E-1

FILTER CLOGGED

OilWiK Pump Module Feb 01, 2008



A334-200/300 GTCP 331−350C

49−91 OIL COOLER AND THERMAL BYPASS VALVE Oil Cooler The oil cooler is of the plate−fin design, with a non−clogging contamination−resistant wavy−fin core. It has two primary components: S Air/Oil Heat Exchanger S Thermal Bypass Valve NOTE:

A serviceable Oil Cooler will keep the oil temperature below the limit of 140 °C during all operation conditions.

Thermal Bypass Valve The Thermal Bypass Valve is of the two−stage poppet type. The first stage has a Thermal Expansion Element for the oil temperature regulation. When the Thermal Bypass Valve is fully open (cold oil), the oil does not flow through the heat exchanger until the oil temperature is more than 60 °C. At this point the Expansion Element starts to close the valve. At an oil temperature of 77 °C the valve is fully closed and all the oil flows through the heat exchanger. The second stage has a Pressure Relief Valve in order to protect the Heat Exchanger from high oil pressure caused. It is spring loaded closed. In case of an obstructed Oil Cooler it opens at a differential pressure of 50psid. There is no oil flow through the Heat Exchanger, the oil flows directly to the lubrication oil filter.

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A334-200/300 GTCP 331−350C

49−91

Air Out OIL COOLER

Air In

A THERMAL BYPASS VALVE 1/3

A Page 45 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−91

THERMAL BYPASS VALVE

OIL COOLER

EXPANSION ELEMENT

Oil Out

Air Out OIL COOLER

Air In

Oil In

A THERMAL BYPASS VALVE

SECTION

A-A 2/3

A Page 45 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−91

THERMAL BYPASS VALVE FUNCTIONS

THERMAL BYPASS VALVE

Thermal Function: Expansion Element starts to close the Valve at 60 °C Valve is fully closed at 77 °C (No Bypass) Bypass Function: Valve opens at 50 psid over HX (Oil Cooler Bypass)

OIL COOLER

EXPANSION ELEMENT

Oil Out

Air Out OIL COOLER

Air In

Oil In

A THERMAL BYPASS VALVE

SECTION

A-A 3/3

A Page 45 Figure 23 FRA US/E-1

OilWiK CoolerFeb Function 01, 2008



A334-200/300 GTCP 331−350C

49−91 DE−OILING SYSTEM OPERATION Low Oil Temperature Sensor The low oil−temperature sensor is installed on the gearbox housing and measures the temperature in the oil reservoir. The temperature signal is transmitted to the ECB. When the ECB receives the start signal from the START P/BSW 2KA in the cockpit and finds that the oil temperature is less than −6.7 °C or the altitude is above 31000 ft, it energizes the De−Oiling Solenoid and the normally closed De−Oiling Valve opens. Oil from the oil pump outlet (to the oil cooler) returns to the pump inlet and mixes with the inlet oil, the pump outlet is de−pressurized. This reduces the load of the oil pump module and thus also for the APU starter motor which is caused by the high viscosity of the cold oil. The ECB de−energizes the De−Oiling Solenoid after the APU reaches 60% speed (65% speed in case of high altitude). The ECB also carries out de−oiling at every APU shutdown between 95% and 7% APU speed. This makes sure that the scavenge elements of the oil pump can remove the oil from the sumps during the shutdown. This also reduces the load of the starter motor at the subsequent APU start. De−Oiling Solenoid Valve The De−Oiling Solenoid Valve is mounted at the Oil Pump Module which is normally spring loaded closed. It is a solenoid operated poppet valve and is operated from the ECB under the following conditions: S APU Start when Oil Temperature <−6.6 _C and speed rising up to 60% N S APU Shut−Down and 95% < N > 7%

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A334-200/300 GTCP 331−350C

49−91 DE-OILING VALVE (NORMALLY CLOSED)

OIL TO THE OIL COOLER

ECB

S OIL PUMP MODULE

OIL FROM THE OIL COOLER

RETURN

REGULATED PRESSURE PUMP INLET


De-Oiling System Schematic WiK Feb 01, 2008


A334−2/3


49−10 POWER PLANT 49−12 APU MOUNTS 49−20 ENGINE 49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING


AUXILIARY POWER UNIT OIL INDICATING

A334-200/300 GTCP 331−350C

49−93

49−93

OIL INDICATING

DESCRIPTION General The Oil Indicating System monitors the oil quantity in the oil reservoir and gives respective indication on the APU System Display in static condition, i.e. when the APU does not operate. Low Oil Quantity Switch The primary component within the Oil Indicating System is the Low Oil Quantity Switch. It is installed at the bottom of the housing of the accessory drive gearbox. The switch stays up into the oil in the integral oil reservoir and transmits the low oil−quantity signal to the ECB, if the oil quantity is at or below the set minimum of 4.1 l. The set minimum agrees with the ADD mark on the oil sight glass on the gravity oil fill−port. When the ECB receives a low−oil quantity signal from the low switch, it transmits the signal to the: S EIS (Electronic Instrument System) S CMS (Central Maintenance System You can read the oil quantity information on the EIS SD (System Display) and the MCDUs (Multipurpose Control & Display Units) in the cockpit on the: S APU page on the System Display S APU SERVICE DATA page on the MCDU

APU AVAIL APU 62 115 400

GEN % V HZ

10

BLEED 35 PSI N %

0 100 5 7 11 3 600

Figure 25

EGT °C

LOW OIL LEVEL

Oil Quantity Indication

Page 48 FRA US/E-1

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A334-200/300 GTCP 331−350C

49−93



Low Oil Quantity Switch WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−93 LOW OIL QUANTITY SWITCH Construction The Low−Oil Quantity Switch has an aluminum body. It holds: S an Electrical Connector S a tube with a Float Assembly and Permanent Magnets S the two Dual−Reed Switches In the lower part of the tube the two dual−reed switches are installed. There is also a welded aluminum float inside the tube on which an alnico V-magnet is installed. It is a permanent magnet. The float is immersed in the oil. When the oil quantity is at the permitted minimum, the magnet of the float opens the two dual−reed switches. The dual−reed switches are redundant. They are connected in parallel and make an OR-gate. Operation When the oil quantity in the reservoir decreases to 4.1 l, the magnet on the float opens the two dual−reed switches. The ECB receives the discrete open signals. A signal from one of the two dual−reed switches is sufficient for the ECB to operate.

Control The ECB transmits the low−oil quantity signal to the EIS and the CMS when the subsequent signals are given: S Low−Oil Quantity Signal and S Oil Temperature is less than 65.55 °C and S Aircraft on Ground Indicating On the APU Page on the EIS System Display There is no oil level advisory−message on the APU page of the SD, if the oil level in the APU oil reservoir is more than the set minimum. You can read the LOW OIL LEVEL advisory message if the oil level in the APU oil reservoir decreased to the set minimum or below this level. The LOW OIL LEVEL advisory message is pulsing green. On APU Service Data Page You can read an OIL LEVEL O.K. indication, if the oil level in the APU oil reservoir is more than the set minimum. You can read an OIL LEVEL LOW indication, if the oil level in the APU oil reservoir decreased to the set minimum or below this level.

Page 50



A334-200/300 GTCP 331−350C

49−93

2LP3 FAULT

ANN−LT

TRANSFORMER ON/R

1LP3

BOARD−ANN LT AND INTFC

FLOAT ASSY

215VU

14KD APU MASTER SWITCH

309PP 2KD ZONE APU

APU CTL 1KD

LOW OIL−QUANTITY SWITCH 59KT8

MAIN SUPPLY 28VDC

4KD APU MAIN RELAY

PERMANENT MAGNETS READ SWITCHES

5000VE

ALUMINUM BODY

ARINC BUSSES

EIS

ECB CMS 59KD


Page 51 Figure 27

LOQ-Electrical Schematic


A334−2/3


49−12 APU MOUNTS 49−20 ENGINE 49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING


AUXILIARY POWER UNIT LOW OIL PRESSURE AND HIGH OIL TEMPERATURE WARNING

49−94

A334-200/300 GTCP 331−350C

49−94

LOP AND HOT WARNING

SYSTEM OPERATION GENERAL The LOP (Low Oil Pressure) and HOT (High Oil Temperature) Warning System has the subsequent primary components: S High Oil Temperature Sensor (HOT SNSR) S Low Oil Pressure Switch (LOP SW) The HOT SNSR and the LOP SW are installed downstream of the oil cooler and the oil pressure regulation valve. They are installed in a manifold which is a part of the line to the mid and the aft sump. HIGH OIL TEMPERATURE SENSOR Construction The HOT SNSR is a RTD (Resistive Temperature Device). It is a nickel−wire thermal−resistant element which can operate in the subsequent temperature range from −53.9 °C to +250 °C). This makes an input operating range for the ECB of 73 to 200 ohms. The sensor has a stainless steel body with a copper tip which protects the electrical components against oil, water and moisture. Operation The HOT SNSR measures the oil temperature downstream of the oil cooler. It transmits the analog oil temperature signal to the ECB. This starts the APU automatic shutdown−sequence (if it is not inhibited) when: S Oil Temperature >147.2 °C for 10 seconds and S APU Speed >95 % Monitoring The sensor is monitored during PUT and Selftest. If the sensor faulty, it will be stored as a CLASS-3 failure with a CMC message: HIGH OIL TEMP SNSR (59KT11).

LOW OIL PRESSURE SWITCH Construction The LOP SW has a microswitch with normally open contacts. This decreases the consumption of electrical power and the corrosion of the contacts. The LOP SW has a hermetically sealed stainless−steel body which protects the electrical components against oil, water, and moisture. Operation The LOP SW monitors the pressure downstream of the oil−pressure regulation valve. When the LOP SW detects low oil pressure, the microswitch closes and makes a ground connection which is transmitted as a discrete signal to the ECB. The ECB starts the APU automatic shutdown−sequence (if it is not inhibited) when: S APU Speed >95% and it receives a low oil−pressure signal for: − 15 seconds when APU oil temperature < −3.9 °C − 1 second when APU oil temperature > −3.9 °C Monitoring The switch is monitored during PUT and Selftest. If the switch is faulty, it will be stored as a CLASS-2 failure with a CMC message: LOW OIL PRESS SW (59KT14). GENERATOR HIGH OIL TEMPERATURE SENSOR Function Additional to the HOT SNSR and the LOP SW there is the Generator High Oil Temperature Sensor (GEN HOT SNSR) incorporated in the APU Generator. The ECB receives its analog signal and thus it monitors the temperature of the generator scavenge oil. If the generator scavenge oil−temperature is too high the ECB starts the APU automatic shutdown−sequence (if it is not inhibited) when the generator oil temperature is more than 185 °C for 1 second. This protects the APU Generator from possible damage.

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WiK

Feb 01, 2008


AUXILIARY POWER UNIT LOW OIL PRESSURE AND HIGH OIL TEMPERATURE WARNING

2LP3 ANN LT

A334-200/300 GTCP 331−350C

49−94

FAULT

TRANSFORMER

ON/R

1LP3 BOARD−ANN LT

AND INTFC

APU ZONE 315 LOP− SWITCH

215VU

14KD APU MASTER SWITCH

HOT− SENSOR

309PP 1KD

ECB SPLY 2KD

APU CTL 28VDC

4KD APU MAIN RELAY

5000VE APU PANEL

EIS

ECB CMS

HIGH OIL TEMPERATURE SENSOR LOW OIL PRESSURE SWITCH

59KD


LOP/HOT-Warning System WiK Feb 01, 2008


A334−2/3


49−20 ENGINE 49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING


AUXILIARY POWER UNIT APU OIL HEATING

A334-200/300 GTCP 331−350C

49−96

49−96

APU OIL HEATING

OIL HEATING DESCRIPTION General The primary component of the APU Oil Heating System is the Oil Heater. The Heater incorporates an Oil Temperature Switch, which monitors the oil temperature in the reservoir of the APU gearbox. Power Supply The APU Oil Heater operates only if the APU Master Switch is off. The oil heater system gets the electrical power from the AC system of the aircraft. It supplies 115 V AC to the SERVICE BUS 113XP through the circuit breaker 1KT, a bus and the relay 4KD to the APU oil heater 59KT16. Function If the oil temperature decreases below 21.1 °C, the temperature switch closes and 115 V AC is supplied to a heater coil. This increase the APU oil temperature to more than the APU compartment temperature during cold soak condition. When the oil temperature increases to above 43.3 °C, the temperature switch opens, and stops the 115 V AC supply to the heater coil. Monitoring The APU Oil Heater is monitored by the ECB but not controlled. When the ECB receives an APU Oil Heater failure message, a CLASS-2 failure is shown on the MCDU (Multipurpose Control and Display Unit): APU OIL HEATER (59KT16).

Page 54 FRA US/E-1

WiK

Feb 01, 2008


AUXILIARY POWER UNIT APU OIL HEATING

A334-200/300 GTCP 331−350C

49−96

BULK CARGO COMPARTMENT

OIL HEATER

GEAR BOX APU COM

CTL

MAIN MODE INTRPT SUPPLY SUPPLY SUPPLY

DC SUPPLY REF

BAT REF BAT APU

NO VDC BCL APU BCL APU

CNTOR

5127VC P1

APU VM

10 113XP−C 115VAC

SVCE BUS 1 24−58−18

1

A 2 3 5

5005VE273

OIL

HEATER

310W

A

5

B3 B1

B2

A

24−53SCH06 X1 X2

49−61SCH01

1KT C/B− APU OIL HEATER 5000VE162

9 UNSD

P1

APU OIL HEATER 40W

A

SURGE CTL VALVE HEATER SCHO1

4KD RELAY− APU MAIN 5000VE162 49−61

59KT16 OIL HEATER− APU 310

APU BOX 5000VE


OilWiK Heater Feb 01, 2008


A334−2/3


49−80 EXHAUST 49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING


AUXILIARY POWER UNIT ENGINE FUEL AND CONTROL

A334-200/300 GTCP 331−350C

49−30

49−30

ENGINE FUEL AND CONTROL

INTRODUCTION

COMP

Purpose The Engine Fuel and Control System supplies metered fuel to the combustor. The metered fuel is the quantity, which is mandatory for the safe and the economic operation of the APU. The fuel quantity supplied is in proportion to the APU load during governed operation. General The engine fuel and control system receives the low pressure fuel from the A/C fuel system through the APU fuel feed line. The APU fuel feed line is installed to the trim tank line. The main components of the Fuel System are the: S FCU (Fuel Control Unit) S Fuel Flow Divider Assembly The ECB computes the fuel/air ratio, corresponding to the APU load. The FCU meters the fuel. It does this in the direct proportion to the command signal transmitted from the ECB. The metered fuel is filtered high−pressure fuel. The Fuel Flow Divider Assembly receives the metered fuel from the FCU. It divides the fuel and supplies it to the Fuel Manifolds in the correct sequence. Fuel pressure is also used as muscle pressure to operate the Load Compressor IGV (Inlet Guide Vane) actuator and the SCV (Surge Control Valve) actuator.

Page 56



A334-200/300 GTCP 331−350C

49−30

ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ BLEED CONTROL VALVE

SURGE CONTROL VALVE

FUEL MANIFOLDS

FUEL CONTROL UNIT

FLOW DIVIDER ASSEMBLY IGV ACTUATOR


Fuel System Design



A334-200/300 GTCP 331−350C

49−30 FUEL CONTROL SYSTEM DESCRIPTION General The FCU (Fuel Control Unit) is the primary component of the Fuel Control System. It is attached to the Oil Pump Module by a V-clamp. The FCU meters the necessary fuel to the combustion chamber and supplies regulated fuel pressure internally to the FMV (Fuel Metering Valve), and externally to the IGVs (Inlet Guide Vanes) and SCV (Surge Control Valve) actuators.

Fuel Shutoff Solenoid-Valve The Fuel Shutoff Solenoid−Valve is a normally closed, electrically opened solenoid valve. During the APU start sequence, it receives a command signal from the ECB to open at 7 % APU speed. On normal or fault shutdowns, the Fuel Shutoff Solenoid−Valve receives a close signal from the ECB.

FCU Inlet Filter The FCU Inlet Fuel−Filter removes unwanted materials from the fuel which is supplied from the APU fuel pump−system to prevent contamination of the downstream components of the APU fuel system. It is equipped with a Visual Clogging Indicator where a red indicator pin extends in case of filter clogging. In this condition an internal Bypass Valve opens to maintain fuel supply. High Pressure Fuel Pump The High−Pressure Fuel Pump is a two gear rotary type which pumps high−pressure fuel. A shaft−seal witness drain−port is located on the bottom of the mounting flange. Fuel or oil leakage from the drain port is an indication that there are internal leakages. Fuel flow at 100% APU speed is 1020 kg/h at a pressure of 800 psi. Fuel Metering Valve The fuel is metered from the Metering Valve, which is operated by an Electronic Torque Motor controlled by ECB. An increased electrical power to the torque motor operates the metering valve and increases the fuel flow. A decreased electrical power decreases the fuel flow. When no electrical power from the ECB is supplied, the torque motor metering−valve moves to the lowest position to allow the minimum fuel flow. The electrical supply to the Torque Motor Metering−Valve stops when the ECB receives one of the subsequent signals: S Protective Shutdown S APU Normal Shutdown S Overspeed Signal

Page 58 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

APU LOW-PRESSURE FUEL SHUTOFF VALVE

ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏ ÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏ ÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏ ÏÏÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏ ÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏ ÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏ ÏÏÏÏ ÎÎÎÎÎ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ ÌÌÌÌÌÌÌÌÌÌÌÌÌÌ ÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏÏ A/C AFT FUEL FEED PUMP

IGV ACTUATOR

FCU INLET FILTER

PRIMARY MANIFOLD

SECONDARY MANIFOLD

SCV ACTUATOR

FUEL CONTROL UNIT


HP FILTER

FLOW DIVIDER ASSEMBLY

REG

SECONDARY DRAIN VALVE

SECONDARY SEQUENCE VALVE

FUEL PUMP

FUEL SOLENOID VALVE

FMV

PRESS. VALVE

M

S

FUEL FLOW METER

ECOLOGY DRAIN SOLENOID

FUEL TEMP SENSOR

ÌÌÌÌ ÏÏÏÏ ÌÌÌÌ ÏÏÏÏ ÎÎÎÎ ÌÌÌÌ ÏÏÏÏ ÎÎÎÎ ÎÎÎÎ Figure 31 FRA US/E-1

PRIMARY DRAIN VALVE

FUEL LP SWITCH

APU SYSTEM DISPLAY

Page 59

49−30

Fuel System Schematic WiK Feb 01, 2008

FUEL HIGH PRESSURE METERED FUEL

ÌÌÌÌ ÌÌÌÌ ÌÌÌÌ

S

DMM

RETURN/(SCAVENGE)

ACCUMULATOR

DRAIN

REGULATED PRESSURE PCD2 AIR



A334-200/300 GTCP 331−350C

49−30 FUEL DISTRIBUTION SYSTEM DESCRIPTION General The Fuel Control Unit supplies the correct quantity of fuel to the APU fuel distribution system. The fuel flows through the distribution system to the combustion chamber where it mixes with the air and burns. The fuel distribution system also has an ecology drain system. The ecology drain system makes sure that the fuel is removed from the fuel atomizers and manifolds during the APU shutdown. The drain fuel is burned in the combustion chamber. System Layout The fuel distribution system consists of the subsequent primary components: S Primary and Secondary Fuel Manifold and Nozzles S Flow Divider Assembly S Ecology Drain System S Fuel Temperature Sensor S Fuel Flow Meter Fuel Manifold and Nozzles The Fuel Manifold is located around the turbine plenum. It is divided into a Primary and a Secondary Fuel Supply, both connected to each of the 12 Dual Orifice Fuel Nozzles. The fuel flows through the primary and secondary fuel manifolds from the flow divider Assembly to the Fuel Nozzles. The fuel manifold ensures an even fuel distribution to the nozzles.

Page 60 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−30

COMP (a)

COMP (b)

LP FUEL FILTER BYPASS VALVE

HP-FUEL FILTER

FUEL SHUTOFF SOLENOID VALVE

FUEL METERING VALVE TORQUE MOTOR

LP-FUEL FILTER CLOGGING INDICATOR

LOW FUEL PRESSURE SWITCH

DRAIN PORT AIR CHECK VALVE

LP FUEL FILTER


Fuel Control Unit WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−30 Flow Divider Assembly The Flow Divider Assembly is supplied with fuel coming from the FCU which controls the fuel quantity. The Flow Divider Assembly splits the fuel into primary and secondary fuel and supplies it to the fuel manifolds. The secondary sequencing valve permits or stops the flow of fuel to the secondary flow path of the flow divider. The valve is spring−loaded closed until the flow of fuel has the maximum quantity of primary fuel which the Fuel Nozzles can atomize accurately. This makes sure that the fuel/air mixture is correct in the combustion chamber during the start sequence. Ecology Drain System When the APU is stopped and no fuel is supplied, the fuel inlets of the Primary and Secondary Drain Valves are spring−loaded closed. Their drain air inlets are open and thus the drain air line is connected to the fuel manifolds. Compressor discharge air which is stored in the Air Tube enters the Fuel Manifolds when the Ecology Drain Solenoid Valve is commanded open by the ECB. Thus remaining fuel is blown out of the Fuel Nozzles. Fuel Temperature Sensor and Fuel Flow Meter The Fuel Temperature Sensor measures the fuel temperature and transmits an analog fuel temperature−signal to the ECB. The Fuel Flow Meter measures the quantity of the fuel which flows through the primary line of the flow divider assembly. It transmits an analog fuel flow quantity−signal to the ECB. These two signals make the closed loop for the ECB which uses them to calculate the accurate fuel quantity necessary for the APU start sequence.

Page 62 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−30

FLOW DIVIDER ASSEMBLY SECONDARY SEQUENCE VALVE

DUAL FUEL NOZZLE ECOLOGY DRAIN CHECK VALVE

SECONDARY FLOW PRIMARY FLOW

FUEL INLET

ECOLOGY DRAIN SOLENOID VALVE

FUEL TEMP SENSOR FILTER SCREEN FILTER SCREEN FUEL FLOW METER

AIR SHROUD

DUAL-ORIFICE TIP ASSEMBLY


Flow Divider Assembly and Fuel Nozzle WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−30 FUEL SYSTEM OPERATION General The ECB acts on the fuel system according to two different schedules: S Acceleration Schedule during Starting S Speed Maintain Schedule during On−Speed Operation Acceleration Schedule The Fuel Temperature Sensor and the Fuel Flow Meter which measures the quantity of the fuel which flows through the primary line of the Flow Divider Assembly transmit analog signals to the ECB. These two signals make the closed loop for the ECB which uses them to calculate the start fuel quantity. During APU starting sequence, when the APU shaft speed (N) is above 7%, the ECB energizes the Fuel Solenoid Shut−Off Valve. Then it supplies the FMV torque motor to provide the correct amount of fuel to comply with the ECB smooth acceleration schedule according to: S Inlet Temperature (T2) S Inlet Pressure (P2) S Fuel Temperature As the FMV operates, fuel pressure opens the Pressurizing Shut−Off Valve against spring force. Because of the low fuel flow during the start of the APU, the Secondary Sequencing Valve of the Flow Divider Assembly is spring−loaded closed. The Primary Drain Valve opens the fuel inlet and closes the Ecology Drain Air Inlet when the fuel pressure is approximately 5 psi. The fuel flows into the Primary Fuel Manifold only, which supplies it to the Primary Fuel Nozzles. After fuel ignition, the APU shaft accelerates, increasing HP-fuel delivered pressure. At approximately 125 psi fuel pressure downstream of the FMV, the Secondary Sequence Valve opens, allowing the Secondary Fuel Manifold to be supplied. The ECB continues to supply the FMV torque motor in order to reach 100 % N speed. During all this acceleration process, the FMV LVDT feedback provides the necessary information for the fuel closed loop control to the ECB. EGT (Exhaust Gas Temperature) is used during starting to limit the fuel schedule to prevent EGT exceedance. This EGT protection overrides the acceleration schedule.

Speed Maintain Schedule During on−speed operation, the ECB controls the FMV torque motor in order to maintain a constant 100% N speed regardless of electrical or pneumatic load applied to the APU. If the speed tends to decrease, due to load effect, the ECB reacts by opening the FMV more to increase the fuel flow to regain the 100% speed reference. During APU load reduction, fuel flow will be reduced to prevent the speed from exceeding 100%.

Page 64



A334-200/300 GTCP 331−350C

ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎ ÎÎÎÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎ ÎÎÎÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎ ÎÎÎÎÎ ÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ

49−30

ECB

APU LOW-PRESSURE FUEL SHUTOFF VALVE

M

LOW FUEL PRESSURE

M

IGV ACTUATOR

N% INLET P INLET TEMP FUEL TEMP EGT MES

FCU CTL LOGIC

FCU INLET FILTER

HP FILTER

FUEL TEMP

APU START

PRIMARY MANIFOLD

SECONDARY MANIFOLD

SCV ACTUATOR

ECS FUEL FLOW

N>7%


REG


REG

SHUTDOWN

FUEL PUMP

APU STOP/SHUTDOWN

PRESSURIZING VALVE

FUEL FLOW

PRIMARY DRAIN VALVE

S

FUEL METERING VALVE

M

FUEL FLOW METER

FUEL SOLENOID VALVE

FUEL LP-SWITCH

ECOLOGY DRAIN SOLENOID

FUEL TEMP SENSOR

Page 65

LOWER ECAM DISPLAY UNIT

Figure 34


FCU

N>7% N<95%

A/C AFT FUEL FEED PUMP

ŸŸŸŸ ÎÎÎÎ ŸŸŸŸ ÎÎÎÎ ÚÚÚÚ ŸŸŸŸ ÎÎÎÎ ÚÚÚÚ ÚÚÚÚ

Fuel System Schematic

FUEL HIGH PRESSURE METERED FUEL

ŸŸŸŸ ŸŸŸŸ ŸŸŸŸ

S

DMM ECOLOGY DRAIN ACCUMULATOR

RETURN/(SCAVENGE) DRAIN

REGULATED PRESSURE PCD2 AIR



A334-200/300 GTCP 331−350C

49−30 Differential Pressure Regulation-Valve The FCU contains a spring−controlled Differential Pressure Regulation−Valve. It operates with the Fuel−Control Torque Motor and the Pressurizing Valve. The high−pressure gear pump supplies always more fuel than necessary for the operation of the APU, this makes sure that sufficient fuel is available under all operation conditions. The Differential Pressure Regulation−Valve permits the excessive fuel, which is more than the limit, to return to the inlet of the FCU inlet fuel−filter. To control the fuel flow, the regulation valve compares the fuel pressure upstream and downstream of the Torque Motor Metering−Valve. It keeps the pressure of the fuel which flows through the metering valve (independently from the fuel quantity) constantly at 50 ± 5 psi. Because of the increase of the fuel pressure in the high−pressure gear pump, the temperature of the fuel increases. The quantity of the warm fuel which flows back to the inlet of the FCU inlet fuel−filter is sufficient to prevent the formation of ice in the filter and the FCU inlet. Actuator Pressure Regulation-Valve The Actuator Pressure Regulation−Valve is a spring−loaded regulation valve. It controls the outlet pressure of the fuel which is used to power the IGV actuator and the SCV actuator. The valve keeps the pressure at 325 ± 25 psi, thus the actuators operate with constant force and speed.

Ecology Drain System The Ecology Drain System removes the remaining fuel from the Primary and Secondary Fuel Nozzles and Manifolds. The drain fuel is burned in the combustion chamber. When the ECB receives a shutdown signal, it starts the over−speed test and an APU cool down if APU bleed air was used. Then it sends a close command to the Fuel Solenoid Valve on the outlet of the FCU. When the Fuel Solenoid Valve closes, the ECB energizes the Ecology Drain Solenoid−Valve. The valve opens and 2nd stage compressor discharge air (PCD2), which is stored in the Ecology Drain Accumulator, flows to the spring-loaded Primary and Secondary Drain Valve. This will permit the PCD2 air to flow through the fuel manifolds and Fuel Nozzles into the combustion chamber. Thus the drain air removes the remaining fuel from the manifolds and atomizers. The check valve at the inlet prevents that drain air flows back to the compressor when the pressure there decreases during the shutdown. The check valve at the outlet prevents that fuel or hot gas from the combustion chamber to flows the accumulator.

Fuel Pump Drain-Port Air Check-Valve The Fuel Pump Drain−Port Air Check−Valve is a check valve which opens at 0.15 psi to permit the seal cavity to drain. The valve is installed on the drain valve port as a backup air seal.

Page 66



A334-200/300

ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ Î ÎÎÎÎÎ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ Î ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ Î ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ Î ÎÎÎÎÎ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ Î ÎÎÎÎÎ ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎ Î ÚÚÚÚÚÚ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ Î ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ Î ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ Î ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÚÚÚ ÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸŸ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ

GTCP 331−350C

49−30

IGV ACTUATOR

PRIMARY MANIFOLD

SCV ACTUATOR

FCU INLET FILTER

SECONDARY MANIFOLD

FUEL CONTROL UNIT

HP FILTER


ACT-REG

dP-REG

FUEL METERING VALVE

M

PRESSURIZING VALVE

PRIMARY DRAIN VALVE

S

FUEL FLOW METER

FUEL SOLENOID VALVE

FUEL LP-SWITCH FUEL TEMP SENSOR

FUEL PUMP DRAIN PORT AIR CHECK VALVE



ECOLOGY DRAIN SOLENOID S

ECB

ACCUMULATOR

Page 67 Figure 35

Fuel Control and Distribution System


A334−2/3


49−17 POWER PLANT DRAIN SYSTEM 49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING 49−73 ANALYZERS


AUXILIARY POWER UNIT APU FUEL LOW PRESSURE WARNING

A334-200/300 GTCP 331−350C

49−34

49−34

APU FUEL LP WARNING

LOW PRESSURE FUEL WARNING DESCRIPTION General The Low Fuel Pressure−Switch is installed on the Fuel Pump Inlet. Monitoring The aircraft APU Fuel Pump−System supplies fuel to the inlet of the APU Fuel Control Unit. A Fuel Low−Pressure Switch, installed at the inlet of the FCU, monitors the pressure of the APU fuel supply at the inlet port. If a fuel low−pressure occurs, the pressure switch transmits this information, via the ECB, to the EIS to generate a related warning message.

Page 68



A334-200/300 GTCP 331−350C

49−34


GEN % V HZ

10

BLEED 35 PSI N %

FUEL LO PR

0 100 FUEL CONTROL UNIT

FLAP OPEN 5 7 11

EGT °C

3 600 FUEL LOW PRESSURE SWITCH

Page 69 Figure 36

Low Pressure Fuel Warning



A334-200/300 GTCP 331−350C

49−34 LOW PRESSURE FUEL WARNING OPERATION General The APU Fuel Low−Pressure Warning System shows a warning on the EIS (Electronic Instrument System) SD (System Display) when the fuel at the FCU (Fuel Control Unit) has a low pressure. This is controlled from the Fuel−Low Pressure Switch. The ECB and the FCMC (Fuel Control and Monitoring Computer) monitor the signals from the Fuel−Low Pressure Switch. If a low fuel pressure occurs an ARINC bus transmits the signal from the the ECB to the EIS. Power Supply When the Fuel Low−Pressure Switch is closed it supplies a ground signal to the FCMC and the ECB. The ECB supplies through an 429 ARINC bus a low fuel pressure signal to the EIS. If the fuel low pressure signal is not available the switch supplies a 28 V DC signal to the FCMC and the ECB. Operation and Indicating When the APU fuel pressure increase to 19.5 ± 8.7 psi the Fuel−Low Pressure Switch opens and transfers a signal to the ECB. The ECB transmits the signal to EIS, this removes the indication FUEL LO PR from the EIS SD. The ECB also stops the signal to the aft fuel feed−pump.

Page 70



A334-200/300 GTCP 331−350C

49−34

2LP3 ANN LT

FAULT

309PP 1KD

TRANSFORMER

ON/R

MAIN SUPPLY

1LP3 BOARD−ANN LT

AND INTFC

2KD

APU CTL

MASTER SWITCH 215VU

4KD APU MAIN RELAY

28VDC

5000VE

ARINC BUSSES

EIS

ELECTRONIC CONTROL BOX [59KD] CMS FCMC

LOW FUEL PRESSURE SWITCH [59KF17] APU FUEL PUMP SYSTEM VENT AND DRAIN VALVE

Page 71 Figure 37

LP Fuel Warning Schematic

REG

FUEL CONTROL UNIT [59KF19]


A334−2/3


49−16 AIR INTAKE SYSTEM 49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING 49−73 ANALYZERS 49−40 IGNITION AND STARTING


AUXILIARY POWER UNIT AIR

A334-200/300 GTCP 331−350C

49−50

49−50

AIR

INTRODUCTION Bleed and Surge-Air System The Bleed and Surge−Air System controls the supply of the APU bleed air to the pneumatic system of the aircraft and prevents a load compressor surge The Bleed-Air System delivers compressed air from the APU Load Compressor for: S MES (Main Engine Start) S Air Conditioning The APU bleed air system includes a Bleed Valve, a flow regulation by means of Inlet Guide Vanes and surge protection by means of a SCV (Surge Control Valve). The Electronic Control Box ensures control and monitoring of these components. The bleed and surge−air system controls the supply of the APU bleed air to the pneumatic system of the aircraft and prevents a load compressor surge Accessory Cooling System An Accessory Cooling System supplies cooling air to the APU Oil Cooler and to the APU compartment. This is achieved by a Fan which supplies ambient air into the APU compartment. An Accessory Cooling Valve determines the amount of compartment cooling air. The system operates independently of the APU Load Compressor and the Bleed and Surge−air system.

Page 72


AUXILIARY POWER UNIT AIR

A334-200/300 GTCP 331−350C

49−50

TO AIRCRAFT PNEUMATIC SYSTEM

ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎ ÎÎÎ ÎÎÎ ÎÎÎ BLEED CONTROL VALVE

ACCESSORY COOLING VALVE

COOLING FAN

COMP

SURGE CONTROL VALVE

IGV ACTUATOR


Air System Design


A334−2/3


49−90 OIL 49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING 49−73 ANALYZERS 49−40 IGNITION AND STARTING 49−60 ENGINE CONTROLS


AUXILIARY POWER UNIT BLEED AND SURGE AIR

A334-200/300 GTCP 331−350C

49−51

49−51

BLEED AND SURGE AIR

DESCRIPTION General The APU Load Compressor supplies the APU bleed air. The quantity changes with the different bleed air demands of the aircraft pneumatic systems. Variable IGVs (Inlet Guide Vanes) which are installed at the load compressor inlet control the quantity of the bleed air. The IGVs are operated by an IGV-Actuator controlled from the ECB. The ECB receives position feedback information from a Actuator-LVDT (Linear Variable Differential Transducer). The bleed and surge air system has the subsequent primary components: S Inlet Guide Vane Actuator S Bleed Flow Sensor S APU Load Bleed Valve S Surge Control Valve

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A334-200/300 GTCP 331−350C

49−51

PCD-(PRESSURE COMPRESSOR DISCHARGE) STG 1

OVBD PCD1 FROM AIR/OIL SEPARATOR PCD2 TO ECOLOGY DRAIN SYSTEM

IGV ACT

ACCESSORY COOLING VALVE

BLEED FLOW SENSOR ASSY

LCIT

DIFFERENTIAL PRESSURE-XDCR TOTAL PRESSURE-XDCR

P2

dP Pt

ELECTRONIC CONTROL BOX S

LOAD BLEED VALVE


AirWiK SystemFeb Schematic 01, 2008

TM

SURGE CONTROL VALVE



A334-200/300 GTCP 331−350C

49−51 Bleed Air System The bleed air flows from the scroll of the APU Load Compressor to the Tee−duct which is installed on the right side of the APU. The APU Load Bleed Valve is installed at the forward end end of the pneumatic Tee−duct on the right hand side of the APU. The Load Bleed Valve stops or permits the bleed air flow from the APU to the pneumatic system of the aircraft. The Load Bleed Valve is operated pneumatically by compressor discharge air from Power Compressor Stage 2. The ECB controls and monitors the APU Load Bleed Valve position. The APU bleed signal comes from the APU BLEED P/BSW on the air overhead panel 225VU in the cockpit. When the ECB receives the APU bleed signal it transmits an open signal to the APU bleed valve depending on flight altitude information from the P2 Sensor and aircraft pneumatic bleed status. The P2−Sensor is attached to the left hand side of the Inlet Plenum. The Load Bleed Valve has a position indicator switch. This transmits discrete open or not open signals to the ECB for the valve position monitoring and indication. The valve position is also visible on the visual position indicator on the shaft end of the valve.

VISUAL POSITION INDICATOR TEST PORT SOLENOID VALVE

Load Compressor Monitoring The efficiency of the Load Compressor is monitored by means of the LCOT (Load Compressor Outlet Temperature) Sensor which sends temperature signals to the ECB. An more and more increasing load compressor outlet temperature is an evidence for decreasing load compressor performance. NOTE:

The LCOT Sensor is structurally identical to the LCIT (Load Compressor Inlet Temperature) Sensor. I.e. a interchange of both sensors is possible in case of LCIT Sensor malfunction.

Figure 40

APU Load Bleed Valve

Page 76 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−51

LOAD BLEED VALVE

LCOT SENSOR

IGV ACTUATOR

INLET PRESSURE SENSOR (P2)


AirWiK SystemFeb Components 01, 2008



A334-200/300 GTCP 331−350C

49−51 Bleed Air Flow Control The APU bleed air flow depends on two basic demand parameters: S MES (Main Engine Start) S ECS (Environmental Control System) An IGV actuator is installed in a right angle position to the IGV assembly geartrain on a mount pad of the load compressor scroll at 6 o’clock position. It is driven by high pressure fuel from the FCU (Fuel Control Unit) and moves the IGV assembly geartrain directly through a pushrod. For each demand the ECB determines a certain IGV Actuator position to satisfy the requested bleed air flow. A Bleed Flow Assembly which contains a Differential Pressure and a Total Pressure Transducer sends Feedback information about the actual bleed air flow to the ECB. The ECB uses this signals to adjust the Surge Control Valve if there is a deviation from the calculated bleed air flow in relation to the actual bleed air flow.

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A334-200/300 GTCP 331−350C

49−51

SECTOR GEARS

IGVs FULLY OPENED

CYLINDRICAL RACK PUSHROD

IGV ACTUATOR MOUNT

IGVs FULLY CLOSED

IGV ACTUATOR


IGVWiK Assembly Feb 01, 2008



A334-200/300 GTCP 331−350C

49−51 Surge Air System The APU SCV (Surge Control Valve) is installed at the aft end of the pneumatic Tee−duct on the right hand side of the APU. The Surge Control−Valve bleeds excess bleed air to avoid a load compressor surge. The surge air flows to the APU exhaust cone. The Surge Control Valve is a hydraulically operated modulating butterfly valve. It uses high pressure fuel supplied from the Fuel Control Unit as the hydraulic power source. The ECB controls and monitors the position of the surge control valve by means of a SCV-LVDT.

LVDT STRAP-ON HEATER

The Surge Control Valve position is not indicated on the APU System Display of the lower ECAM, but it is possible to get position information via Alpha Call Up [SCV] if the aircraft is equipped with ACMS (Aircraft Condition Monitoring System). The Surge Control Valve mainly serves for bleed flow correction. I.e. it adjusts the actual bleed flow which is determined by the IGV position in case of a bleed flow deviation. The ECB receives actual bleed flow information from the Bleed Flow Sensor Assembly. Each difference between the momentarily allowed value stored in the ECB and the calculated value causes a control signal from the ECB to the surge control valve. Thus the Surge Control Valve corrects the airflow. Any time the ECB commands the APU Load Bleed Valve to close, the Surge Control Valve will be commanded open to prevent a compressor stall due to reverse flow. Additional the ECB monitors the APU during operation for reverse flow conditions by means of the LCIT (Load Compressor Inlet Temperature) Sensor.

1

113 XP-C 115 VAC SVCE BUS1

NOTE:

SERVO VALVE

SERVO FUEL PORTS

VISUAL POSITION INDICATOR

OPEN

On LH-Airplanes Eff. 103−199 only

Figure 43

CLOSE

1

Surge Control Valve

Page 80 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−51

SURGE CONTROL VALVE

Ptot XDCR

dP XDCR

LCIT SENSOR

BLEED FLOW ASSEMBLY


Surge Air System Components WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−51 BLEED AND SURGE AIR OPERATION Load Bleed Air Control The APU bleed signal comes from the APU Bleed P/BSW 7HV on the Air Overhead Panel 225VU in the cockpit. The signal goes through the BMCs (Bleed Monitoring Computers) to the ECB. The BMCs cancel the APU bleed demand signal under the following conditions: S BMCs sense an Overheat Condition in the area − L/H Wing or − L/H Pylon or − APU Duct NOTE:

When there is an overheat condition detected on LH Wing/Pylon or APU Duct during MES (Main Engine Start), the APU Bleed Valve will stay open until starter cut out of the starting Engine. When the ECB receives the APU bleed demand signal it transmits an open signal to the APU bleed valve solenoid under the following conditions: S APU Master Switch and APU Bleed P/BSW on S APU Speed (N) >95 % S No Auto Shutdown Condition S Flight Altitude is < 23 000ft When the APU Bleed Valve is in the fully open position, the position indicator switch of the valve transmits an open signal to the ECB. The ECB supplies this signal to the BMCs for engine bleed valve and X-bleed valve logic. The IGVs opening angle which is determined by the ECB refers to the momentarily operation of the pneumatic user systems. If there is a ECS demand signal (Pack Operation) from the ZC (Zone Controller) to the ECB, the IGVs will set in proportion to the demand signal to open (IGV angle 50° – 0°). For MES the ECB receives the demand signal from the EIVMUs (Engine Interface and Vibration Monitoring Units) and the IGVs will fully open (IGV angle -20°). The IGV position will always be corrected by OAT (Outside Air Temperature) sensed from LCIT and P2−Sensor and limited in case of high EGT and high altitude sensed by EGT Probes (T5) and P2−Sensor.

Page 82



A334-200/300 GTCP 331−350C

49−51

ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ Î ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ PCD1−AIR

APU BLEED

FROM AIR/OIL SEPARATOR

ECB

OIL COOLER T2

IGV CONTROL LOOP

HV

MES IGV-POS

SCV POSITION

SCV LOGIC

P2

BCV OPEN

IGV-POSITION SCV-POSITION LCOT N PT dP LCIT (T2) P2

ZC

EIS

TO ECOLOGY DRAIN SYSTEM

COMP COOL. VALVE

Ptot-XDCR

S

Pn

BCV

APU SYSTEM DISPLAY

E/WD

PCD2−AIR

FUEL

dP-XDCR

LABEL 37 BIT 11

TM

IGV ACTUATOR

COOLING FAN

BCV OPEN COMMAND N > 95% LCIT < 177 °C P2 > 5.96 PSI S/D

IGV POSITION dP = P-RATIO PT T2

LVDT

LCIT SENSOR

INLET PRESSURE SENSOR (P2)

Ptot SENSOR

LVDT

SCV

TM

FUEL

LVDT FEEDBACK

OPEN X-FEED VALVE

LVDT FEEDBACK

ECS

LCOT TEMP

BMC 1/2/3/4

ADIRU

Page 83 Figure 45

Air System Schematic



A334-200/300 GTCP 331−350C

49−51 Bleed Air Flow Control For every APU bleed demand (MES or ECS) the ECB calculates a certain IGV position and a resulting pressure ratio (dP/Pt). The ECB receives feedback information from the Bleed Flow Assembly concerning the actual bleed air flow at the Load Compressor outlet. If there is a deviation between the commanded and the actual pressure ratio, the ECB will send a command signal to the SCV torque motor in order to adjust the bleed air flow. Thus the Surge Control Valve opens or closes to regulate the amount of the airflow to the aircraft.

Page 84



A334-200/300 GTCP 331−350C

49−51


APU AVAILABLE LOGIC

FAULT

APU MASTER SWITCH

ON

FAULT

APU BLEED

dP Pt IGV POSITION

ON/R

-

IGV CONTROL

START

dP Pt

AVAIL

+

ECS-Signal

ON

ZONE TEMPERATURE CONTROLLER ENGINE INTERFACE VIBRATION MONITORING UNIT

STATIC PRESSURE CHANNEL

BLEED VALVE MES-Signal

BLEED MONITORING COMPUTERS

SCV DRIVER

SCV

LOAD COMPRESSOR

DIFFUSER

DIFFERENTIAL PRESSURE TRANSDUCER TOTAL PRESSURE TRANSDUCER

BLEED FLOW ASSEMBLY

Page 85 Figure 46

Air Flow Control Schematic


A334−2/3


49−91 OIL STORAGE AND DISTRIBUTION 49−93 OIL INDICATING 49−94 LOP AND HOT WARNING 49−96 APU OIL HEATING 49−30 ENGINE FUEL AND CONTROL 49−34 APU FUEL LP WARNING 49−50 AIR 49−51 BLEED AND SURGE AIR 49−52 ACCESSORY COOLING 49−70 INDICATING 49−71 POWER INDICATING 49−72 TEMPERATURE INDICATING 49−73 ANALYZERS 49−40 IGNITION AND STARTING 49−60 ENGINE CONTROLS 49−61 CONTROL AND MONITORING


AUXILIARY POWER UNIT ACCESSORY COOLING

A334-200/300 GTCP 331−350C

49−52

49−52

ACCESSORY COOLING

SYSTEM DESCRIPTION Cooling Airflow The accessory cooling system operates independently of the APU load compressor and the bleed and surge−air system. A Cooling Fan supplies sufficient cooling air to the oil cooler to keep the lubricating oil in the correct temperature range. It also supplies cooling air to the APU compartment to remove the heat which comes from the APU surface. The Cooling Fan Assembly is of the one−stage axial−flow type and the accessory drive gearbox turns the cooling fan rotor. The compartment cooling air flows through an outlet and through the Compartment Cooling Valve into the APU compartment. Compartment Cooling Valve The Compartment Cooling Valve decreases the cooling air outflow to the APU compartment. The valve operation depends on PCD-1 air pressure and thus on flight altitude. The Compartment Cooling Valve is opened until a flight altitude of 10000 ft. Above this altitude, the valve starts to close and will be fully closed at a flight altitude of 20000 ft due to low PCD-1 air pressure. Compartment cooling airflow is the only achieved by cooling airflow through the fixed orifice outlet.

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AUXILIARY POWER UNIT ACCESSORY COOLING

A334-200/300 GTCP 331−350C

49−52

COOLING AIR DUCT

OIL COOLER

COOLING FAN

COOLING FAN ASSY

COMPARTMENT COOLING VALVE

COMPARTMENT COOLING VALVE COOLING AIR OUTLET (FIXED ORIFICE)


Compartment Cooling Components WiK Feb 01, 2008


COMP

A334−2/3




AUXILIARY POWER UNIT INDICATING

A334-200/300 GTCP 331−350C

49−70

49−70

INDICATING

INTRODUCTION General The indicating system monitors the APU speed and the EGT (Exhaust Gas Temperature). You can also see on the MCDU (Multipurpose Control & Display Unit) the unserviceable LRUs and test results for the APU system. Power Indicating The power indicating system monitors the APU speed in revolutions per minute (rpm). Two speed sensors transmit a signal to the ECB 59KD. The ECB gives a speed signal to the EIS (Electronic Instrument System). The EIS shows the APU speed in percent on the APU system page at the SD (System Display). Temperature Indicating The temperature indicating system monitors the Exhaust Gas Temperature of the Auxiliary Power Unit. Two rakes, each with two thermocouples, transmit a signal to the ECB. The ECB gives an EGT signal to the Electronic Instrument System (EIS). The EIS shows on the APU page at the System Display (SD) the APU EGT in °C. Analyzers The BITE (Built−In Test Equipment) of the ECB analyses the fault data of the APU. The ECB has logics for statistics used for health monitoring and life data of the APU. The ECB analyses data about the APU life and the APU faults. The DMM (Data Memory Module) also keeps the APU life data. DATA MEMORY MODULE

Figure 48

DMM Location

Page 88 FRA US/E-1

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Feb 01, 2008



A334-200/300 GTCP 331−350C

49−70

SYSTEM REPORT/TEST 5/6 ATA:36 AIR BLEED

APU

LEAK DETECTION

PRESS/TEMP

AVAIL APU 62 115 400

GEN % V HZ

10

CROSS FEED

ATA:38 WATER/WASTE TOILET ATA:45 MAINT ONBOARD MAINT SYSTEM ATA:49 APU

BLEED 35 PSI

APU

RETURN

N %

FUEL LO PR

0 100 FLAP OPEN 5 7 11

EGT °C

3 600

LOW OIL LEVEL

APU SYSTEM DISPLAY

MULTIPURPOSE CONTROL & DISPLAY UNIT


System Display & MCDU WiK Feb 01, 2008


AUXILIARY POWER UNIT INDICATION

A334-200/300 GTCP 331−350C

49−70 ECAM PAGE PRESENTATION General The APU indications are displayed on the Lower ECAM (Electronic Centralized Aircraft Monitoring) APU System Display. This page is called up either manually or automatically during APU start.

available at the DMC input, the needle is not displayed and the digital indication is replaced by amber XX. Exhaust Gas Temperature

Avail Indication Green AVAIL message computed by the APU Electronic Control Box is displayed when APU speed N (% RPM) is above 95% confirmed after two seconds. Then, the APU is available to provide bleed air and/or electrical power. Nothing is displayed in the other cases (or when the status of the APU is not transmitted to the DMC). APU Generator The APU GEN indication gives information for the APU Generator concerning load, voltage and frequency. The relevant value is in amber color if a parameter is out of range. Bleed Pressure The APU BLEED air pressure is a green digital indication with 2 psi resolution and a range from 0 to 98 psi. It is the difference between APU bleed air pressure given by the ECB and the corrected average static pressure from ADIRU 1. The indication is replaced by amber XX when one of the pressure data is not available. Speed Indication The APU Speed N is displayed by a Needle on a white analog scale from 0% to 120% and a digital indication below the scale. The red line limit is pictured by a fixed red segment from 107% to 120%. The needle and the digital indication are in green color if speed range is 107% < N > 0%. They are in red color if speed is ≥ 107%. The digital indication has a resolution of 1% speed. When N > 120%, the needle stays at the maximum position of 120%. When speed information is not

The EGT (Exhaust Gas Temperature) is displayed by a Needle on a white analog scale from 300 °C to 1300 °C and a digital indication below the scale. The EGT red line limit is pictured by a movable red segment which varies from 1260 °C to 700 °C during APU start and is established at 665 °C if APU is available. The red segment ends at 1300 °C. The needle and the digital indication are in green color if the EGT is below the red line limit. They are green pulsing when EGT is below the red line limit and an advisory threshold is triggered by the ECB. They are in red color if the EGT has reached the red line limit. The digital indication has a resolution of 5 °C resolution. When 300 °C < EGT > 1300 °C the needle stays at the minimum (or maximum) position. The digital value can vary from −70 °C to 2045 °C. When no information is available, the needle goes out of view and the digital indication is replaced by amber XX. Fuel Low Pressure The amber FUEL LO PR (Fuel Low Pressure) indication is displayed when the pressure upstream the Fuel Control Unit is too low. It is not displayed in all other conditions. Flap Open The green FLAP OPEN indication is displayed when the air intake flap is fully open. It is not displayed in all other conditions. Low Oil Level The green LOW OIL LEVEL indication pulses when the oil in the gearbox reaches the low level and needs servicing.

Page 90


AUXILIARY POWER UNIT INDICATION

A334-200/300 GTCP 331−350C

49−70


GEN % V HZ

10

BLEED 35 PSI N %

FUEL LO PR

0 100 FLAP OPEN 5 7 11 3 600

EGT °C

LOW OIL LEVEL

Page 91 Figure 50

APU System Display


A334−2/3




AUXILIARY POWER UNIT POWER INDICATING

A334-200/300 GTCP 331−350C

49−71

49−71

POWER INDICATING

SYSTEM DESCRIPTION General The power indicating system monitors the APU speed. Two Speed Sensors are installed between the load compressor and the air intake housing and transmit the speed as RPM (Revolutions Per Minute) to the ECB. The ECB transmits the signal to the EIS (Electronic Instrument System) which indicates the APU speed in percent on the APU SD (System Display).

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Feb 01, 2008


AUXILIARY POWER UNIT POWER INDICATING

A334-200/300 GTCP 331−350C

49−71 0.

SPEED SENSOR (Typical)

SPEED SENSOR 1 [59KV26]

SPEED SENSOR 2 [59KV27]


Speed Sensors WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT TEMPERATURE INDICATING

A334-200/300 GTCP 331−350C

49−72

49−72

TEMPERATURE INDICATING

SYSTEM DESCRIPTION General The temperature indicating system monitors the Exhaust Gas Temperature of the APU. Two rakes, each with two EGT Thermocouples, transmit a signal to the ECB. The ECB supplies the EGT signal to the EIS (Electronic Instrument System). The EIS displays the APU EGT in °C on the APU System Display. Function Four EGT Thermocouples are installed in the exhaust cone at the turbine discharge. The Thermocouples (referred to as the Thermocouple Rakes) are connected together. Each Thermocouple Rake is connected to the ECB which reads the average temperature of the two Thermocouple Rakes. If a failure of one Thermocouple Rake occurs, the ECB takes the value of the remaining Thermocouple Rake and transmits this EGT signal to the EIS.

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AUXILIARY POWER UNIT TEMPERATURE INDICATING

A334-200/300 GTCP 331−350C

49−72

THERMOCOUPLE PROBE

EGT THERMOCOUPLE RAKES

ALUMEL (NON-MAGNETIC)

THERMOCOUPLE RAKE #2 [59KV35]

CHROMEL (MAGNETIC)

THERMOCOUPLE RAKE #1 [59KV34]


EGT Thermocouples WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−70 INDICATING SYSTEM OPERATION General The ECB transmits specific life data and all fault data to the CMS (Central Maintenance System) and to the DMU (Data Management Unit). The CMS collects the data and shows the results on the MCDU (Multipurpose Control & Display Unit). You can also print the data on the cockpit printer. The ACMS (Aircraft Condition Monitoring System) collects the BITE data from the DMU for the APU health monitoring. You can have direct access to the parameter data of the APU system, or you can print the APU condition reports. There are two reports available for the APU system: S APU MES/IDLE REPORT <13> S APU SHUTDOWN REPORT <14> TEMPERATURE INDICATING SYSTEM The temperature indicating system has interface with the: S EIS (Electronic Instrument System) S APU System Display S CMS (Central Maintenance System) S Control and Monitoring System

Monitoring EGT Thermocouples are monitored during PUT, IOT and Selftest. In case of a faulty probe a Class 3 Fault is stored and CMS shows ”EGT TCPLE RAKE 1” or ”EGT TCPLE RAKE 2”. If both Rakes are faulty before APU start, a auto shutdown will occur and a Class 2 fault is stored. CMS shows ”EGT TCPLE RAKE 1” and ”EGT TCPLE RAKE 2” warning. If the same fault occurs during APU operation, the APU will continue running without EGT monitoring and bleed supply is no longer possible. Automatic Shutdown The Electronic Control Box initiates an ASD (Automatic Shut Down) under the following conditions: S TIT (Turbine Inlet Temperature) calculated from the EGT is more than 1260 °C (EGT ranges from 1250 °C to 700 °C with increasing speed) at the APU start S TIT calculated from the EGT is more than 1232 °C (EGT = 665 °C) at ISA (International Standard Atmosphere) and APU operate. S Both Thermocouple rakes are defective during the APU start

EGT Thermocouple The EGT thermocouple is a Chromel−Alumel device which has two probes of different lengths. The EGT thermocouples produce a voltage in proportion to the EGT. This voltage is supplied through a shielded cable to the ECB. Four EGT thermocouples are installed in the exhaust cone at the turbine discharge. The thermocouples (referred to as the thermocouple rakes) are connected together. Each thermocouple rake is connected to the ECB. The ECB reads the average temperature of the two thermocouple rakes and transmits the EGT signal to the EIS. If a failure of one thermocouple rake occurs, the ECB takes the value of the remaining thermocouple rake and transmits this EGT signal to the EIS.

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A334-200/300 GTCP 331−350C

49−70

SIGNAL

LABEL 176

CONDTR

SELECT N

59KV26

SPEED SENSOR 1

HIGH SIGNAL

RPM

CONDTR

>107% OVER

SPEED

59KV27

>107%

ARINC 429

SPEED SENSOR 2 SPEED SENSOR 2

59KV27

SIGNAL CONDTR

BROCKEN WIRE

OPEN EGT 1

300VU SYSTEM DISPLAY

59KV34 THERMOCOUPLE

RAKE 1

LABEL 175 T5

SELECT HIGH

EGT

SIGNAL

59KV35

CONDTR

THERMOCOUPLE

BROCKEN WIRE

RAKE 2

OPEN EGT 2 FUEL FLOW CLOCK

ARINC 429

TRANSMIT

DMM APU MEMORY

RECEIVE

59KV20

APU MEMORY MODULE

Page 97

MCDU 100VU

Figure 53 FRA US/E-1

MODULE

SPEED SENSOR 1

59KV20

59KV26

59KB ECB

Indicating System Schematic WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49−70 RPM POWER INDICATING SYSTEM The power indicating system has interface with the: S EIS (Electronic Instrument System) S APU System Display S CMS (Central Maintenance System) S Control and Monitoring System Speed Sensor (Monopole Transducer) Each Speed Sensor has a: S Permanent Magnet S Shim Pack S Pole Piece S Coil S Housing At 7% APU speed, the speed sensors give a frequency of approximately 292 Hz and a voltage of approximately 0.2 V AC from peak current to peak current. At 120 % APU speed the speed sensors give a frequence of approximately 5007 Hz and a voltage of up to 70 V AC from peak current to peak current. The speed sensors give the frequency in proportion to the APU speed.

ANALYZERS The BITE (Built−In Test Equipment) of the ECB analyses the fault data of the APU. The ECB has logics for statistics used for health monitoring and life data of the APU. The ECB analyses data about the APU life and the APU faults. The memory module also keeps the APU life data. The ECB transmits specific life data and all fault data to the Central Maintenance System and to the Data Management Unit. The CMS collects the data and shows the results on the MCDU (Multipurpose Control & Display Units). You can also print the data on the cockpit printer. The ACMS (Aircraft Condition Monitoring System) collects the BITE data from the DMU for the APU health monitoring. You can have direct access to the parameter data of the APU system, or you can print the APU condition reports. The ACARS (Aircraft Communication Addressing and Reporting System) receives the data from the DMU and permits a direct and real−time transmission of data in digital form. The VHF 3 system transmits the data between the aircraft and the ground station. The MDDU (Multipurpose Disk Drive Unit) collects the data from the DMU in its memory. You can read this data through the GSE (Ground Support Equipment)

Operation The speed sensors measure the APU speed and transmit a frequency to the ECB. The ECB monitors the power indication during all APU operating conditions. The ECB starts the automatic shutdown sequence if: S the APU speed is more than 107% S both speed sensors are defective Monitoring The Monopole Sensors are monitored during IOT. When a sensor is faulty a Class 3 Fault is stored and CMS shows ”SPEED SNSR P 26 or P27”. If both sensors are defective the APU will shut down and a Class 1 fault is stored with the related CMS message ”SPEED SNSR P 26 or P27”.

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A334-200/300 GTCP 331−350C

49−70

PRINTER

MCDU

CMC 1

ACARS MU

CMC 2

DMU

BITE

ELECTRONIC CONTROL BOX Page 99 Figure 54 FRA US/E-1

ACMS Schematic WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT ANALYZERS

A334-200/300 GTCP 331−350C

49-73

49−73

ANALYZERS

The MCDU shows the APU data in Normal Mode and Menu Mode (Interactive Mode) through the CMS. NORMAL MODE During Normal Mode all systems continuously transmit all Class 1, 2 and 3 messages to the CMS. The MCDU display shows the messages when the LAST LEG REPORT is set. MENU MODE (INTERACTIVE MODE) The APU CMS (Central Maintenance System) Interactive Mode is available on the MCDU display when the APU Master Switch is set to on, the SYSTEM REPORT/TEST is set and APU selection is made. The MCDU display shows the related APU system data and the faults transmitted by the ECB. The APU menu includes the: S LAST LEG REPORT S PREVIOUS LEGS REPORT S LRU IDENT S GND SCANNING S CLASS 3 FAULTS S TEST S GROUND REPORT S SHUTDOWNS S SERVICE DATA S TROUBLE SHOOT DATA

Previous Leg Report The purpose of this item is to present the internal and external fault messages, concerning the system that appeared during the previous 64 flights. This item is the sum of the LAST LEG REPORT items over several flights. The screen shows a maximum of 2 failures, it shows other failures when you push the next page key on the MCDU keyboard. If the system has no failures the screen shows the aircraft identifier and the NO FAULT DETECTED legend. Line Replaceable Unit Identification The purpose of this item is to present the part number of the selected system (in this case the Electronic Control Box). The serial number and the data base number is also displayed. NOTE:

Only electrical LRUs with internal stored data are shown on this page. (Electronic Control Box).

Last Leg Report The purpose of this item is to present the internal and external Class 1 and 2 fault messages, concerning the system, that appeared during the last flight. The screen shows a maximum of 2 failures, it shows other failures when you push the next page key on the MCDU keyboard. If the system has no failures the screen shows the NO FAULT DETECTED legend.

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A334-200/300 GTCP 331−350C

49-73 MCDU MENU

SYSTEM REPORT/TEST 5/6 ATA:36 AIR BLEED

MCDU MENU ACARS ACMS CMS

APU LAST LEG

PRESS/TEMP

SAT

MAINT

FAULTS

PREVIOUS LEGS

REPORTS

CROSS FEED

ATA:38 WATER/WASTE TOILET ATA:45 MAINT ONBOARD MAINT SYSTEM ATA:49 APU

MCDU

CLASS 3

REPORT

LEAK DETECTION

TEST

LRU IDENT GND SCANNING SHUTDOWNS TROUBLE SHOOT

GROUND

DATA

APU

RETURN

REPORT

SERVICE

DATA

RETURN

SELECT DESIRED SYSTEM

APU

1/3

LAST LEG REPORT UTC

JAN 09

ATA

1/10

CLASS

1406 492317 INLET PRESS XDCR (59KE22) 1408 499414 LOW OIL PRESS SW (59KT14)

RETURN

APU

PREVIOUS LEGS REPORT

2>

2>

PRINT

LEG DATE UTC ATA CLASS 02 NOV26 1739 495121 1 > IGNITION EXCITER (59KA10) 06 NOV05 1406 LOW OIL QUANTITY

RETURN

499300

APU

LRU IDENTIFICATION ECB P/N:

388394−X1Y100ZZ

S/N:

143

S/W:

DOWN LOADER : AA MICBAC : BB CONTROL : CC

1>

PRINT

RETURN

PRINT


MCDU Menu (1/4) WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49-73 Ground Scanning The purpose of this item is to reconfigure the computer BITE as being in flight. Fault messages (Class 1, 2, 3, internal and external) detected by the BITE during the activation of this function, are displayed in real time. When you push the line key adjacent to the GND SCANNING indication, and if there are system failures on the ground, the screen shows the related failures. NOTE:

All failures are only shown on the MCDU and are not memorized in the nonvolatile memory.

Trouble Shooting Data The purpose of this item is to present internal snapshot data concerning any failure of any class for airline engineering use. When you push the line key adjacent to the TROUBLE SHOOT DATA, the Trouble Shoot Data for each CLASS 1 and CLASS 2 fault which are shown in the last leg or previous legs reports are shown. If the system has no fault, NO FAULT DETECTED is shwon. Class 3 Faults The purpose of this item is to present the Class 3 Fault Messages, concerning the system, that appeared during the last flight. The screen shows a maximum of 2 failures, it shows other failures when you push the next page key on the MCDU keyboard. If the system has no failures the screen shows the NO FAULT DETECTED legend. ECB System Test When you push the line key adjacent to the TEST indication, the Electronic Control Box starts the APU BITE Test (Self−Test of the ECB) and the APU TEST page comes up and shows the message TEST IN PROGRESS. If the ECB finds no failure during the test, the result TEST OK is shown and instructions to set the system back to normal configuration. If the ECB finds a failure during the test, the related ATA Number, the Failure Class and the Maintenance Message are shown. If the APU is in operation and the APU speed is more then 7% the message TEST NOT AVAILABLE comes on. If the APU does not operate and the APU Master Switch switch on the panel 215VU is in the off position, the message ACTIVATE SYSTEM / SET APU M/S TO ON is shown on the APU TEST page.

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A334-200/300 GTCP 331−350C

49-73

APU

APU

DATE UTC ATA LEG NOV26 1739 492315 02 LOAD COMPRESSOR INLET TEMP SNSR (59KE1)

TEST OK SET APU M/S TO OFF IF APU NOT REQUIRED

APU LAST LEG

CLASS 3 FAULTS

CLASS 3

REPORT

TEST

FAULTS

PREVIOUS LEGS

REPORTS

TEST

LRU IDENT GND SCANNING SHUTDOWNS TROUBLE SHOOT

GROUND

DATA

REPORT

SERVICE

RETURN

DATA

NOV05 1406 499413 06 HI OIL TEMP SNSR (59KT11)

RETURN

PRINT

RETURN

PRINT

OR

APU

GROUND SCANNING UTC

1/3

JAN 09

ATA

CLASS

APU

TROUBLE SHOOTING DATA DATE

1/12

UTC

APU TEST

CLASS

ATA

1406 49317 INLET PRESS XDCR (59KE22)

2>

NOV14 0800 STARTER VOLTAGE MONITOR SHOWS LOW VOLTAGE

>

492315 LOAD COMPRESSOR INLET TEMP SNSR (59KE1)

3>

1408 494252 CONTACTOR (5KA)

2>

NOV13 0700 SHUT DOWN OCCURRED WITH NO LRU FAULT DETECTED

>

499300 LOW OIL QUANTITY

2>

RETURN

PRINT

RETURN

PRINT

RETURN

PRINT





A334-200/300 GTCP 331−350C

49-73 Shutdowns When you push the line key adjacent to the SHUTDOWNS indication, the screen shows the cause of the shutdown and the related class 1 LRUs. A list of the shutdown faults and text of the possible causes is shown in the tables 1, 2 and 3. If the system has no failures the screen shows the NO FAULT DETECTED legend. Ground Report The purpose of this item is to present the internal fault messages of the APU system which appeared since the last flight at the moment of the request. The screen shows a maximum of 2 failures, it shows other failures when you push the next page key on the MCDU keyboard. If the system has no failures the screen shows the NO FAULT DETECTED legend. Service Data When you push the line key adjacent to the SERVICE DATA indication, on the menu page, the screen shows the subsequent information: − APU Serial Number − APU Operation Hours − APU Cycles − Oil Level (OK or LOW) − Oil Chip Detector (OK or CHECK)

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A334-200/300 GTCP 331−350C

49-73

APU

APU LAST LEG

CLASS 3

REPORT

FAULTS

PREVIOUS LEGS

REPORTS

1/5

SHUTDOWNS DATE

UTC

TEST

EVENT > JAN09 1406 NO ACCELERATION FUEL CONTROL UNIT (59KF19)

GND SCANNING SHUTDOWNS

LRU DATA >

LRU IDENT TROUBLE SHOOT

GROUND

DATA

REPORT

SERVICE

DATA

RETURN

ACCEL < 0.3% / SEC TIME OUT FLIGHT PHASE: 09

RETURN

APU

PRINT

APU

SERVICE DATA

GROUND REPORT

1/2

JAN 15

S/N

:

143

UTC

HOURS CYCLES

: :

1034 352

1610 494252 CONTACTOR (5KA)

2>

OIL LEVEL OIL CHIP

: :

OK (LOW) OK (CHECK) DMM >

1613 242351 GENERATOR (8X5) / OIL PUMP MODULE (5100KT9)

1>

RETURN

PRINT

RETURN

ATA

CLASS

PRINT





A334-200/300 GTCP 331−350C

49-73

APU

1/5

SHUTDOWNS UTC

DATE

EVENT > JAN09 1406 NO ACCELERATION FUEL CONTROL UNIT (59KF19) LRU DATA > ACCEL < 0.3% / SEC TIME OUT FLIGHT PHASE: 09

RETURN

PRINT

APU

LRU TROUBLE SHOOT DATA DATE:NOV14 FAULT CODE NUMBER : INLET PRESS TRANSDUCER SHOWS OUT OF RANGE FAULT CALSS : FAULT COUNT : FLIGHT PHASE : OTHER FAULTS PRESENT XXX XXX XXX XXX

RETURN

1/3

UTC:0800 XXX

2 1 09

PRINT

APU

SDN TROUBLE SHOOT DATA UTC:1407

DATE:JAN09 NO ACCELERATION MODE : MASTER SWITCH : START INIT : START CONT : SPEED > 7% : SPEED > 95% : FLAME ON : BLEED SWITCH :

PRINT

APU

LRU TROUBLE SHOOT DATA

RETURN

: : : : : : : :

APU

SDN TROUBLE SHOOT DATA

2/3

UTC:0800 XXX IN OPER ON YES NO NO YES ON

PRINT

ON NO LOW NO NO NO YES

RETURN

PRINT

APU

LRU TROUBLE SHOOT DATA DATE:NOV14 FAULT CODE NUMBER MES MODE COOLDOWN FUEL PRESS SW IGV POS >70 DEG SCV POS >30 DEG IGV TRIM IN AIR

RETURN

2/2

UTC:1407

DATE:JAN09 NO ACCELERATION MES MODE : COOLDOWN : FUEL PRESS SW : IGV POS >70 DEG : SCV POS >30 DEG : IGV TRIM : IN AIR :

IN OPER ON YES YES NO NO YES ON

RETURN

DATE:NOV14 FAULT CODE NUMBER MODE MASTER SWITCH START INIT SPEED > 7% SPEED > 95% FLAME ON BLEED SWITCH XXX XXX XXX XXX

1/2

: : : : : : :

3/3

UTC:0800 XXX

ON NO LOW NO NO NO YES

PRINT





A334-200/300 GTCP 331−350C

49-73

MCDU MENU ACARS ACMS CMS SAT

ACMS LABEL

ALPHA

SPECIAL FUNC/

REPROGRAM

MCDU

MAINT

LIST OF

DUMP DATA

PREV REP

SAR DATA

REPORTS

SAR/DAR

REPORTS

STOP

CHANNEL 6

STORED DATA

STORED

MAN REQ

MAN REQ

DATA RECORDING

SELECT DESIRED SYSTEM

ACMS: MAN REQ REP PRINT (<-DUMP

SEND ->)

1/5


SEND ->)

2/5


SEND ->)

3/5

01: ENG CRUISE

07: ENG MECH ADVISORY

14: APU SHUTDOWN

02: A/C PERFORMANCE

09: ENG DIVERGENCE

15: LOAD REPORT

04: ENG TAKE OFF

10: ENG START

16: PROGRAMMABLE REPORT

05: ENG ON REQUEST

11: ENG RUN UP


06: GAS PATH ADVISORY

13: APU MES/IDLE


RETURN

RETURN

SCROLL

PRINT <- ->

SELECT

SCROLL

PRINT <- ->

SELECT

RETURN SCROLL

PRINT <- ->

SELECT


ACMS Menu WiK Feb 01, 2008



A334-200/300 GTCP 331−350C

49-73 ACMS REPORTS General The ACMS can produce two APU condition reports through the Data Management Unit: S MES (Main Engine Start/Idle Report S APU Shutdown Report. The reports can be launched from the MCDU. The reports are available on a hard copy from the printer or on ground through the ACARS if installed. MES/IDLE Report The Main Engine Start/Idle report monitors the APU related data when the APU bleed air is used for a Main Engine Start. The displayed informations are beside others: S Serial Number S Operating Hours S Cycles S Load Compressor Temperatures and Pressures S APU Speed S EGT APU Shutdown Report The APU Shutdown report monitors the APU related data and is started when an abnormal shutdown is detected. The last ten seconds before the shutdown are recorded. The displayed informations are beside others: S Serial Number S Operating Hours S Cycles S APU Speed S EGT S Load Compressor Temperatures and Pressures S Valve Positions S Reason for Shutdown

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A334-200/300 GTCP 331−350C

49-73

A340

PAGE 01 OF 01

APU SHUTDOWN REPORT <14>

ACID

DATE

UTC

FROM TO

F LT

CODE CNT

C1 XXXXXXX 99AAA99 99.99.99 AAAA AAAA XXXXXXXXXX 999X 999 .. A340 APU MES/IDLE REPORT <13> ACID

DATE

UTC

FROM TO

F LT

PAGE 01 OF 01 CODE CNT

C1 XXXXXXX 99AAA99 99.99.99 AAAA AAAA XXXXXXXXXX 999X 999 .. PRV PH

TIEBCK DMU IDENTIFICATION

MOD AP1 AP2

PRV PH

TIEBCK DMU IDENTIFICATION

MOD AP1 AP2

C2 099 99.9 XXXXXX SXXXXX VXXXXX CXXXXX XXX 099 099 .. TAT

ALT

MN

SYS (........BLEED

S TAT U S . . . . . . . ) A P U

C 3 X 9 9 . 9 X 9 9 9 9 0 . 9 9 9 9 9 9 9 . 9 9 1111 1111 1 1111 1111 9 . 9 9 1 . .

C2 099 99.9 XXXXXX SXXXXX VXXXXX CXXXXX XXX 099 099 .. ASN TAT

ALT

SYS (........BLEED

MN

AHRS

ACYC

ECID

ACW2

ACW3

S TAT U S . . . . . . . ) A P U E1 9999 99999 99999 999999 XXXXX XXXXX

..

C 3 X 9 9 . 9 X 9 9 9 9 0 . 9 9 9 9 9 9 9 . 9 9 1111 1111 1 1111 1111 9 . 9 9 1 . . REASON : XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX ASN

AHRS

ACYC

ECID

PRE EVENT , ’Y14.1’ SECONDS INTERVAL

ACW1

E1 9999 99999 99999 999999 XXXXX .. ESN

EGTA GLA WB

PT

P2A

NA

LCOT LCIT IGV SCV LOT HOT

EGTA GLA WB

PT

P2A

LCOT LCIT IGV SCV LOT HOT

N1 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N1 999999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N2 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N2 999999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N3 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N3 999999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

N4 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

PREVIOUS APU START

N5 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

STA EGTP NPA LOT LCIT

N6 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..

V1 999 X999 999 X99 X099 ..

N7 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 .. N8 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 .. N9 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 .. AT EVENT N0 999 X999 999 9999 99.9 99.9 X999 X099 X99 099 X99 X99 ..


APU Report No. 13 and No. 14 WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT IGNITION AND STARTING

A334-200/300 GTCP 331−350C

49−40

49−40

IGNITION AND STARTING

INTRODUCTION General The Ignition and Starting System is necessary to start the APU. The APU start sequence is initiated from the cockpit and is controlled by the Electronic Control Box. During starting, the electrical starter motor drives the APU and initial combustion is initiated by the ignition system.

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A334-200/300 GTCP 331−350C

49−40

OVERHEAD PANEL APU

STARTER MOTOR

MASTER SW FAULT

COMBUSTION CHAMBER

ON/R

START AVAIL ON

IGNITER PLUG EXTERNAL AIR

IGNITION EXCITER

ELECTRONIC CONTROL BOX Page 111 Figure 61 FRA US/E-1

Starting &Feb Ignition System Design WiK 01, 2008



A334-200/300 GTCP 331−350C

49−40 DESCRIPTION General The Ignition and Starting It operates electrically and is supplied from the aircraft electrical system. The APU battery is assisted by the APU TRU (Transformer Rectifier Unit) if powered through the external power or if the main engine generator supplies sufficient power to start the APU. The APU battery and the APU TRU are installed adjacent to the BULK cargo compartment. The starting system turns the engine to more than its self−sustaining speed. The ignition system then ignites the fuel/air mixture in the APU combustion chamber. Ignition System The ignition system gives the constant high−energy ignition which ignites the fuel/air mixture in the combustion chamber. It operates during the start sequence until the APU speed is between 7 % and 50 %. It also operates during the APU operation if the APU speed decreases to between 95% and 50%. The Ignition System is controlled by the ECB. Starting System The starting system turns and accelerates the main shaft of the APU to 50%. You can operate the starting system from the APU panel in the cockpit. The ECB controls the start sequence. For manual rotation of the APU main shaft, a cap protected Manual Drive Shaft is installed on the front of the starter motor. This device is used for borescope inspection. A yellow Brush Wear Indicator Pin which you can see in a clear plastic cover indicates the serviceability of the starter brushes. When the yellow Indicator Pin is not visible you have to replace the starter motor. ATTENTION: Three consecutive start attempts are permitted without cool down. After the third attempt the starter motor must cool down for at least 60 minutes.

Figure 62

5000VE (Bulk Cargo Compartment)

Page 112 FRA US/E-1

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A334-200/300 GTCP 331−350C

49−40

1/6

Page 113 FRA US/E-1

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A334-200/300 GTCP 331−350C

49−40

IGNITION EXCITER

2/6

WARNING! 18KV OUTPUT Page 113 FRA US/E-1

WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−40

IGNITION EXCITER

IGNITER PLUG

IGNITION LEAD

3/6


WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−40

IGNITION EXCITER

IGNITER PLUG

IGNITION LEAD

4/6


WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−40

MANUAL DRIVE SHAFT

STARTER MOTOR

IGNITION EXCITER

IGNITER PLUG

IGNITION LEAD

5/6


WiK

Feb 01, 2008



A334-200/300 GTCP 331−350C

49−40

STARTER MOTOR BRUSH WEAR INDICATOR

MANUAL DRIVE SHAFT

STARTER MOTOR

IGNITION EXCITER

IGNITER PLUG

IGNITION LEAD

6/6

WARNING! 18KV OUTPUT Page 113 Figure 63 FRA US/E-1

Ignition & Feb Starting Components WiK 01, 2008



A334-200/300 GTCP 331−350C

49−40 STARTING AND IGNITION OPERATION Starting and Ignition Schedule When you put the MASTER SW in the ON position, the: S A/C relay energizes S ECB 59KD starts the pre−start test S APU Fuel Pump energizes S Fuel Solenoid Valve energizes S APU Air Inlet Door opens S Back-Up Start Contactor closes S IGVs close When the START pushbutton is set to ON the following sequence is initiated: S the ON light in the pushbutton comes on S the APU page of the EIS SD is shown S the De−Oiling Solenoid Valve, used to unload the lube pump, opens at low oil temperature S the Main Start Contactor closes and energizes the Starter Motor, when the ECB receives the signal that the Air Intake Flap is open − the Starter Motor starts to turn and − the Starter Clutch Module is engaged S the Back-Up Start Contactor closes 7% SPEED S the Ignition Unit is energized and supplies high−voltage electrical energy to the Igniter Plugs S the Fuel Shut−Off Solenoid Valve is energized and the fuel metering valve starts to regulate the fuel flow

S

S

S

S

S S S

50%-SPEED (54.5% > 25000 ft. or 65% > 31000 ft.) the ECB de−energizes the main start contactor (at 54.5% APU speed above 25000 ft.) (at 65% APU speed in cruise above 31000 ft.) − the Main Start Contactor stops the electrical power to the Starter Motor − the timed acceleration logic of the ECB accelerates the APU speed automatically the ECB de−energizes the APU ignition system (at 54.5% APU speed above 25000 ft.) 60% SPEED the De−Oiling Valve closes (when open on cold days) (at 65% APU speed in cruise above 31000 ft.) 95% SPEED the ON light in the START pushbutton distinguishes, the AVAIL light comes on in green and the AVAIL message appears on the ECAM APU page. The Back-Up Start Contactor opens the APU is on governed speed. At that speed, the APU generator can be used and APU bleed can be switched on the ECB sends a permanent 95 % signal to the other systems 100% SPEED The ECB compensates the electrical and pneumatic loads by acting on the fuel flow to maintain an APU constant speed at 100 %. The various APU parameters are displayed on the ECAM APU page.

Page 114



A334-200/300 GTCP 331−350C

49−40

AVAIL

If P2 < 5.45 psi (ALT > 25000 ft )

ON

AVAIL

If ALT > 31000 ft

BACK-UP START CONTACTOR CLOSES

ON

BACK-UP START CONTACTOR OPENS

MASTER SW P/BSW ON START P/BSW PRESSED

START CONTACTOR CLOSES STARTER ENGAGES

START CONTACTOR OPENS STARTER DISENGAGES STARTING

ECB PRESTART TEST

0%

7%

50% 54.4%

65%

95% 100%

IGNITION - ECB IS ENERGIZED - START SYSTEM IS ARMED - APU LP FUEL PUMP IS ARMED - AIR INTAKE FLAP OPENS

IGNITION ON

IGNITION ON

IGNITION OFF

IGNITION OFF

ON SPEED

IGNITION ON IF SPEED DROPS BELOW 95%

AIR BLEED AND DC ELECTRICAL POWER AVAILABLE

Page 115 Figure 64

Starting and Ignition Schedule



A334-200/300 GTCP 331−350C

49−40

ALT > 25000 ft

ALT > 31000 ft

FUEL SOLENOID VALVE ENERGIZED IGNITION SYSTEM ENERGIZED STARTER MOTOR ENERGIZED DE-OILING SOLENOID ENERGIZED APU INLET DOOR OPEN

A/C RELAY ENERGIZED

START SW ON LT

START SW AVAIL LT

MSW ON LT

MSW FAULT LT M/SW PUSHED

START SW PUSHED

7%

50%

54.4%

60%

65%

95%

100%

107%

109%

Page 116 Figure 65

Starting and Ignition Conditions



A334-200/300 GTCP 331−350C

49−40

APU MASTER

14KD

S/D APU AVAIL

FAULT ON/R

N>7% N<50%

28VDC

59KA31 A

S/D

START 2KA

IGNITION LEAD A [59KA32]

on DLH A/C Eff.104−199

STOP

SWITCH

”START IN PROGRESS” OUTPUT

AVAIL ON

Start Contactor GRND Signal (for max. 90s if: - Start Switch pushed - Inlet Flap open - no protective S/D - N<50% (55% in high ALT

215VU

309PP

59KA10 IGNITION EXITER

59KA31 B

34KD RELAY

ACCELERATION CONTROLED

28VDC

1KD

BY ACCEL.LOGIC

IGNITER PLUGS [59KA31]

10KA BACKUP START 2KD 28VDC

LABEL 352

4KD APU MAIN RELAY

IGNITION EXCITER [59KA10] IGNITION LEAD B [59KA33]

CONTACTOR

START CONTACT

5000VE

BIT 16 LABEL 352 ARINC 429

2KD 6KA 5KA START

STARTER FUSE

BIT 25

CONTACTOR

5000VE

LABEL 351 STARTER MOTOR

BIT 26 MCDU 100VU

Page 117 Figure 66

59KB ECB

Starting and Ignition Schematic

M

8KA STARTER MOTOR

STARTER MOTOR [8KA]

STARTER CLUTCH MODULE [5100KA5]



A334-200/300 GTCP 331−350C

49−40 Start Contactor [5KA] The Start Contactor is installed in the APU box 5000VE. It is a heavy duty contactor which supplies the electrical power to the starter motor. Back-Up Start Contactor [10KA] The Back-Up Start Contactor is installed at frame 79 in the aft underfloor compartment. It is a heavy duty contactor which disconnects the electrical power to the starter motor, in case of a fail close main start contactor.

Page 118



A334-200/300 GTCP 331−350C

49−40

162ZW

5000VE

BACK-UP START CONTACTOR

5112VC-A

5108VC-A

APU

CTL

COM MAIN MODE INTRPT SUPPLY SUPPLY SUPPLY

START CONTACTOR

DC SUPPLY REF BAT REF BAT APU APU NO VDC BCL APU BCL APU CNTOR VM

FUSE

OIL HEATER

APU BOX (5000VE)

Page 119 Figure 67

APU-Box 5000 VE



A334-200/300 GTCP 331−350C

49−40 APU SHUTDOWN OPERATION Shutdown Initiation and NBPT The ECB starts a normal APU S/D (Shut Down) when you push the APU MASTER P/BSW from ON/R to OFF. The ECB immediately sends a S/D signal to aircraft systems which causes the bleed air valve to close. With the MASTER SW set to off, the ECB provides a time slot of 15 seconds to allow a NBPT (No Break Power Transfer) between the APU electrical generator and other active electrical aircraft power sources (Engine or External Power). Cool Down Period After this NBPT the field excitation of the APU generator is de-energized and the ECB starts a cool down period of 85 seconds whether bleed was selected or not, and the altitude is below 23000 ft. In this period the APU decelerates to 84% with a rate of 1%/sec. and then deceleration is reduced to 0.5%/sec until 82% speed. In the remaining 65 seconds the APU stays on 82% speed. NOTE:

If the altitude is higher than 23000 ft. the cool down period is set to zero seconds and the APU decelerates from 100% down to 0% continuously.

Shutdown State After the cool down period the ECB tests the overspeed protection circuit, and thus the APU enters the shutdown state. At the same time the AVAIL legend in the START P/BSW distinguishes. During the APU shutdown the ECB activates the ecology drain solenoid and de-energizes the fuel solenoid in the Fuel Control Unit. At the same time the De-Oiling Solenoid Valve is energized. The EGT and the APU speed decrease and the de-oiling valve opens. 7% Speed At 7% APU speed the ECB de-energizes or closes the subsequent items: S FWD fuel feed pump S De-Oiling valve S Ecology Drain Solenoid S A/C APU Fuel Valves S APU Fuel Feed Pump(s) S Air Intake Flap

SPEED POINT and RATE

DURATION

100% SPEED RATE 1% / sec

16 sec

84% SPEED RATE 0.5% / sec 82% SPEED

4 sec

65 sec

0% SPEED

Figure 68

Cool Down Period

Page 120



A334-200/300 GTCP 331−350C

49−40

STOP SWITCH (GROUND)

APU MASTER

GND

SWITCH 14KD

FAULT

N 95 FOR 2 SECONDS

GND

ON/R

33−14

PROTECTIVE S/D INHIBITED S/D

28VDC

SHUTDOWN

STOP SWITCH 231VU

GND

STOP SEQUENCE

2KA

10WF

12WG

SHUTDOWN

START

START

AVAIL

AIR/GROUND (OPEN=AIR) INTERRUPT SUPPLY (28VDC) MAIN POWER SUPPLY (28VDC)

ON

215VU

FLAP CLOSE COMPLETE FLAP CLOSE

GND

FAIL 3 SEC.

1KL 925VU

POWER UP TEST

MAIN ENGINE START (28VDC) BOOST FOR

WING ICE

35KD

PROTECTION

30−11

2KL 990VU

CLOSED WHEN MAIN LANDING COMPRESSED

5KD 58KD

GROUND

SUPPLY

LGCIU 1

LABEL 353

ENGINE START 28VDC

E I V MU 1 , 2 , 3 , 4

2KD 28VDC 1KD

4KD

28KS

APU

MAIN

Page 121

5000VE

Figure 69

28VDC 27KS

APU Shutdown Controls

EMER STOP

BIT 13

OPEN

DRY/WET MOTORING

34KD INTERNAL SUPPLY

TRUE EMERGENCY

N2 50 START VALVE

ENERGIZED FOR ENGINE

35KD

21−63

ECS DEMAND

24−23

VARY SPEED/GEN LOAD

45−12

OMS

ARINC 429

5WF

ENERGIZED WHEN

ELECTRONIC CONTROL BOX 59KD

FIRE DETECTION IN APU COMP: −IN FLIGHT− MANUALLY

−ON GROUND− AUTOMATICALLY


A334−2/3




AUXILIARY POWER UNIT ENGINE CONTROLS

A334-200/300 GTCP 331−350C

49−60

49−60

ENGINE CONTROLS

APU CONTROL AND MONITORING INTRODUCTION GENERAL The Engine Control System is divided in two main systems S Power Control System S Emergency Shutdown System Power Control System The main part of the Power Control System is the Electrical Control Box. The Electronic Control Box provides full authority digital control over the APU throughout the complete operating envelope. It monitors the APU, controls its performance and gives self protection. To achieve APU control, the Electronic Control Box interfaces with the APU and the aircraft systems. Multiple sensors and self−monitoring enable a fault tolerant operation of the APU. The ECB receives the APU fault detection signals. It transmits this data and the control and the monitoring signals to the other A/C systems. The ECB prevents the APU start or shuts it down if it finds that important LRUs fail or operate incorrectly. The ECB is installed behind a rack in the RH sidewall panel in the BULK cargo compartment. Emergency Shutdown System The Auxiliary Power Unit is equipped with an Emergency Shutdown System. If the ECB receives the emergency shutdown signal, it starts the APU shutdown immediately.

Figure 70

ECB Location

Page 122 FRA US/E-1

WiK

Feb 01, 2008


AUXILIARY POWER UNIT ENGINE CONTROLS

A334-200/300 GTCP 331−350C

49−60

INDICATION

AIR INTAKE FLAP

FUEL SYSTEM

IGNITION & STARTING


OIL SYSTEM

AIRCRAFT SYSTEMS AIR SYSTEM


CTL & MON Simplified Diagram WiK Feb 01, 2008


A334−2/3




AUXILIARY POWER UNIT CONTROL AND MONITORING

A334-200/300 GTCP 331−350C

49−61

49−61

CONTROL AND MONITORING

SYSTEM DESCRIPTION General The ECB provides full authority digital APU control from the start initialization, during the acceleration, at the governor speed to the shutdown. The ECB monitors the APU speed, the APU temperatures, the load compressor air flow, and other critical parameters based on signal inputs from the accessory sensors and the control switches. The ECB communicates with the aircraft systems through the ARINC 429 busses. These data are used for the calculation and to continuously control: S Fuel Flow S IGV Position S Surge Control Valve Position The ECB also controls the subsequent systems: S Starter Motor S Igniters S Fuel Control Shutoff Valve S Air Intake Flap The ECB communicates with the aircraft systems through the ARINC 429 busses. The subsequent LRUs are controlled by separate torque motor currents: S Fuel Control Assembly S IGV Actuator S Surge Control Valve

The ECB controls and monitors the APU with the subsequent Line Replaceable Units (LRUs): S Generator Oil Temperature Sensor S Air Intake Actuator S Inlet Guide Vanes LVDT (Linear Variable Differential Transformer) S LCIT (Load Compressor Inlet Temperature) Sensor S LCOT (Load Compressor Outlet Temperature) Sensor S Inlet Pressure Transducer S Fuel Temperature Sensor S Fuel Flow Meter S SCV (Surge Control Valve) LVDT S Total Pressure Transducer S Differential Pressure Transducer S Speed Sensor #1 S Speed Sensor #2 S Thermocouple Rake #1 Exhaust Gas Temperature S Thermocouple Rake #2 Exhaust Gas Temperature S Low Oil Temperature Sensor S De−Oil Solenoid Valve S High Oil Temperature Sensor S APU Oil Heater

Page 124



A334-200/300 GTCP 331−350C

49−61

AVAIL LIGHT

SURGE CONTROL VALVE

BLEED VALVE

START LIGHT

CENTRALIZED MAINTENANCE SYSTEM

G E ELEC GEN A R OIL B FCU PUMP O X


IGV CTL

P2/LCIT SPD XDCR

ECAM PAGE

STARTER

Pt/dP

FAULT RELAY

IGNITION UNIT ATOMIZER VALVE ECOLOGY DRAIN TC RAKES

AIRCRAFT SYSTEMS

AIR INTAKE SYSTEM

Page 125 Figure 72

Engine Control Diagram



A334-200/300 GTCP 331−350C

49−61 ELECTRONIC CONTROL BOX BITE General The Electronic Control Box performs several tests to isolate any failure or failed component. The tests performed by the ECB are: S PUT (Power Up Test) S IOT (In Operation Test) S Self Test The ECB also applies protective shutdown logics. Any detected failure or failed component will cause a maintenance message which is stored in a non volatile memory.

Power-Up Test The Power-Up Test is performed automatically as soon as the ECB is electrically supplied for at least three seconds. During the Power-Up Test all the components are tested, except those for which the APU must be running. E.g. the speed sensors are not tested during the Power Up Test.

Fault Isolation Principle When a sensor fails, a computed value from another sensor or a synthesized value is used by the ECB, and the Auxiliary Power Unit can be operated. The Electronic Control Box tests are divided into: S ECB Internal Test S APU LRUs (Line Replaceable Units) Test − Sensors − Motors − Air Intake Flap Any detected failure or failed component causes a maintenance message to be stored in a non volatile memory which can be interrogated from the MCDU (Multipurpose Control & Display Unit).

Self Test The Self Test is performed by maintenance crew from the MCDU in the cockpit while the APU is not running. The Self Test lasts three seconds. During the Self Test, the same elements are tested as during the Power-Up Test.

In Operation Test The In Operation Test is a cyclic test performed automatically when the APU is running. The torque motors, the solenoids and most of the switches are not tested, but all of the sensors are tested.

Page 126



A334-200/300 GTCP 331−350C

49−61

POWER UP TEST

MSW SWITCH ON POWER UP TEST COMPLETE NO SHUTDOWN NO START SPEED < 7% MSW ON

TEST ACTIVATION FROM MCDU

AND AND

IN OPERATION TEST SELF TEST ANALYSIS

TEST NOT OK APU OPERATION UNSAFE

TEST SIGNALS

REPLY SIGNALS

TEST OK

APU OPERATION NORMAL/DEGRADED OR

CMC

FAULT MEMORY

APU LINE REPLACEABLE UNITS

APU OPERATION APU SHUTDOWN

APU PROTECTIVE SHUTDOWN LOGICS

BITE


ECB BITE-Logic



A334-200/300 GTCP 331−350C

49−61 ELECTRONIC CONTROL BOX General The ECB is a microprocessor−based digital electronic controller that does the primary part of the APU system logic. The ECB does this for all modes of the APU operation. The internal CPU (Central Processing Unit) processes the program data kept in an EPROM (Erasable Programmable Read Only Memory). The program gives the control and the internal tests of the system. A RAM (Random Access Memory) keeps the results of the temporary calculations that change continuously (such as the fuel schedules and the speed rate commands). A processor gives the Built−In Test Equipment (BITE) functions. It transmits the data through the ARINC 429 Bus of the ECB and the RS232 interface. The ECB transmits and gets all information through the J1 main connector on the rear panel of the ECB. It is possible to download the ECB software via the RS232 connector at the front. This enables the customer to install the ECB, with its A/C related software. Onboard Replaceable Modules The Control and Communication OBRMs (On Board Replaceable Modules) are installed in the ECB. These contain the software for control and data transfer between the aircraft systems and the ECB. All data between the aircraft and the ECB are transmitted on the ARINC 429 data bus systems. The Control OBRM #1 contains the software to control the data transfer between the ECB and the APU data memory module. These are used for the APU health monitoring. The Communication OBRM #2 has a logic for all ARINC 429 labels to and from the aircraft systems as required for the: S CMS (Central Maintenance System) S EIS (Electronic Instrument System) S ACMS (Aircraft Condition Monitoring System) if installed

Page 128



A334-200/300 GTCP 331−350C

49−61


GARRETT GMBH

ALLIED SIGNAL AEROSPACE DEVELOPEMENT AND MANUFACTURED BY BODENSEEWERK GERAETETECHNIK GMBH

UNIT


P/N

304486−XX

S/N

143

IDENT NUMBER

DATE

ECB IDENTIFICATION PLATE

OBRM NUMBER

1/2 ONBOARD REPLACEABLE MODULE

Page 129



A334-200/300 GTCP 331−350C

49−61


GARRETT GMBH

ALLIED SIGNAL AEROSPACE DEVELOPEMENT AND MANUFACTURED BY BODENSEEWERK GERAETETECHNIK GMBH

UNIT


P/N

304486−XX

S/N

143

DATA MEMORY MODULE

IDENT NUMBER

DATE

ECB IDENTIFICATION PLATE

OBRM NUMBER

2/2 ONBOARD REPLACEABLE MODULE

Page 129 Figure 74

Electronic Control Box



A334-200/300 GTCP 331−350C

49−61 APU DATA ANALYSIS The analysis data of the APU is divided into two sections: S APU Life Data S APU Fault Data APU Life Data The APU DMM (Data Memory Module) keeps the APU life data. The ECB also keeps the APU life data at the same time as the Data Memory Module. When the DMM fails, the ECB continues to store the data. When you install a new Data Memory Module, the ECB transmits all life data to the Data Memory Module. When you install a new Electronic Control Box, the Data Memory Module transmits the memory content to the new ECB. The interface between the ECB and APU memory module is made through a serial bus. The APU life data contains: S APU Serial Number S Number of the APU Starts S Number of the APU Operating Hours S Number of the unsuccessful Starts S Number of the High−Oil Temperature Shutdowns S Turbine Life Consumed APU Serial Number The APU serial number is kept in the memory module. The memory module sets the serial number and the ECB reads this information. APU Starts Shows the number of the APU starts. An APU start is counted when the APU speed is more than 95%. APU Operating Hours Shows the total run time in hours, where the APU speed was more than 95%. The hours are stored after shutdown when the APU speed is less than 7%. Number of unsuccessful Starts Shows the number of unsuccessful starts of the APU. It is counted when a start aborted shutdown is available. NOTE:

Number of HOT Shutdowns Shows the number of HOT (High Oil Temperature) shutdowns of the APU. It is counted when a HOT shutdown or a generator shutdown is available. NOTE: This Information is not displayed on the MCDU. Turbine Life consumed This shows for example the highest APU turbine temperature at an APU start. Access to this information is through the MCDU. When you set the SERVICE DATA on the APU menu or to the two ACMS reports. You can also get access to all information through an RS232 interface at the ECB. APU Fault Data The BITE memory of the ECB keeps the APU Fault Data. The ECB transmits the data, through an ARINC 429 bus, to the CMS and the DMU. The MCDU shows the data. The BITE (Built In Test Equipment) of the ECB can detect the failure of LRUs (Line Replaceable Units). If the ECB starts an automatic shutdown of the APU, the BITE fault memory (Non Volatile) of the ECB keeps the LRU failure and shutdown fault information. The CMS function of the MCDU gives access to this fault data. It sends a command to the ECB with fault data on ARINC Label 227 and the ECB supplies the fault data as words with ARINC Label 356. APU Data Memory Module The APU Data Memory Module contains a Non Volatile EEPROM (Electrically Erasable Programmable Read Only Memory) based memory storage device. This device is scheduled for 126 entries. The APU memory module has seven memory allocation pages, each of them stores up to 64 different data. The pages store the subsequent data: PAGES

DATA

0

APU Data

1 to 4

Labels

5

Test Data

6 and 7

Reserved

This Information is not displayed on the MCDU.

Page 130



A334-200/300 GTCP 331−350C

49−61 SYSTEM INTERFACES Power Supply The Electronic Control Box is electrically supplied by the APU Battery, the Aircraft DC Network and/or from the APU Transformer Rectifier. It is supplied with 28 V DC from the: S 709PP APU HOT BUS through the C/B 58KD S 401PP ESS BUS through the C/B 35KD S 309PP APU BAT BUS through the C/B 1KD S 909PP APU TRU BUS through the C/B 3KD The ECB continuously monitors its internal voltages and starts a shutdown if a voltage failure occurs. Master Switch Pushbutton The Master Switch provides the ECB with a supply and reset signal and with a shutdown signal. The Electronic Control Box sends a signal to the Fault Light when a shutdown occurs. Start Pushbutton When the ECB receives the start signal from the Start Pushbutton, the start sequence is initiated. The ECB illuminates the ON light during APU start sequence. The AVAIL light in the START pushbutton comes on when the APU speed is above 95%.

EIVMUs The ECB receives the MES (Main Engine Start) signal from the EIVMUs (Engine Interface and Vibration Monitoring Units). The MES mode is active when a MES signal from the EIVMU1 or EIVMU2 or EIVMU3 or EIVMU4 is available and the APU Bleed P/BSW is pushed to the on position. This sets the IGV position in a fixed position in proportion to the inlet temperature, or 0° if the A/C is in flight. These permit a correct MES. BMCs The ECB receives the APU bleed valve command signal from the BMCs (Bleed Air Monitoring Computers. This signal is used to control the APU bleed valve depending on bleed leak status. Memory Module A Memory Module mounted on the APU inlet plenum stores and exchanges the following information with the ECB: S APU Serial Number S APU successful Starts (N > 95%) S APU unsuccessful Starts (N < 95%) S APU Turbine Life consumed S APU Operating Hours

Emergency Stop An emergency stop signal causes an immediate shutdown of the APU. The four sources for emergency stop signals are: S External Power Control Panel Shut-Off Pushbutton S Refuel/Defuel Panel Shutdown Pushbutton S AFECU (Automatic Fire Extinguishing Control Unit) S Fire Handle Pushbutton. LGCIU 1 The ECB receives the Flight/Ground logic from the LGCIU #1 (Landing Gear Control and Interface Unit). This signal is used for automatic shutdown inhibition logic and for failed sensor logic.

Page 131



A334-200/300 GTCP 331−350C

49−61 APU Fuel Pump The Electronic Control Box sends a fuel demand signal to the APU fuel pump logic. FCMCs The Electronic Control Box sends a fuel demand signal to the Fuel Control and Monitoring Computer. ECS The ECB receives the bleed demand signal from the ECS (Environmental Control System) i.e. from the Zone Controller. This signal is used to control the Inlet Guide Vanes and the surge control valve in proportion to the ECS demand signal. The ECB provides the Environmental Control System with the APU bleed valve open signal. BCL 3 The ECB sends an APU available signal to the Battery Charge Limiter 3. CGU The ECB receives a speed variation demand signal from the Generator Control Unit. This signal is used to vary APU speed so that the generator outputs (voltage and frequency) stay in range. SDAC The ECB sends to the SDACs the indications to be displayed on the ECAM APU page and shutdown information to trigger the corresponding warning. CMC The ECB is a type 1 computer. The ECB receives flight information from the Centralized Maintenance Computer 1 and sends maintenance parameters to both CMCs. DMU The ECB sends maintenance parameters to the Data Management Unit. This information is used for the Aircraft Condition Monitoring System.

Page 132



A334-200/300 GTCP 331−350C

49−61

POWER SUPPLY

APU FUEL PUMP

MASTER SWITCH PUSHBUTTON

FCMCS ECS

START PUSHBUTTON EMERG STOP


LGCIU 1

BCL 3

GCU SDAC 1

EIVMUs

SDAC 2 BMCs

MEMORY MODULE

BITE

CMC 1 CMC 2

DMU Page 133 Figure 75

ECB Interfaces



A334-200/300 GTCP 331−350C

49−61 APU SHUTDOWNS Normal Shutdown The ECB starts a normal APU shutdown when you push the APU MASTER SW P/BSW from ON/R to OFF. The ECB immediately sends a S/D signal to aircraft systems which causes the bleed air valve to close. Protective Shutdowns A protective shutdown logic shuts down the APU automatically whenever continued APU operation would result in damage to the aircraft, the APU or the ECB. The shutdown sequence is the same as the normal shutdown sequence except that there is no 85 seconds cooling period. Automatic Shutdown An automatic shutdown is always started from the subsequent shutdown logics: S Overspeed Shutdown S ECB 1A Shutdown S Emergency Shutdown If the ECB receives one of these shutdown commands the ECB starts a APU shutdown without a cool down cycle and without a BITE check. During an APU automatic shutdown the MASTER CAUT lights come on and a single chime sounds, the ECB closes the fuel solenoid valve, the isolation shutoff valve and the APU LP fuel pump, the APU shuts down without a time delay. The fault output of the ECB transmits a signal to the MASTER P/BSW 14KD and on the EWD the subsequent warning comes on: S APU FAULT S AUTO SHUTDOWN S MASTER SWITCH ____OFF When the APU MASTER P/BSW has been push to the off position, the AUTO SHUTDOWN and the MASTER SWITCH ____OFF indication goes off. The air intake flap closes when the APU speed is less than 7 %.

Inhibited Shutdowns The subsequent shutdowns are inhibited (when the aircraft is in flight or on the ground) between the 1st main engine start and the last main engine shut down (i.e. from flight phase 2 to 9) and the APU speed is above 95%. These shutdown conditions are: S Under−Speed Shutdown S Start Aborted shutdown (with its split shutdown reasons) S Low Oil Pressure Shutdown S Air Intake Flap not open Shutdown S Load Compressor Overtemperature Shutdown S High Oil Temperature Shutdown S Generator High Oil Temperature Shutdown S Oil Filter Clogged Shutdown S ECB 1B Shutdown S Main Power Interrupt Shutdown S Overtemperature Shutdown Emergency Shutdown The APU Emergency Shutdown−System stops the APU in case of emergency. If the ECB receives the emergency shutdown signal during the operation of the APU, it stops the APU immediately without a cool down cycle. If the ECB receives the emergency shutdown signal during the cool down cycle of a shutdown, it stops the APU also immediately. The shutdown sequence is the same than an APU automatic shutdown without a cool down cycle. Emergency Shutdown initiation can be initiated either manually from the APU FIRE PUSH P/BSW in the cockpit, the APU SHUT OFF P/BSW on the external Power Control Panel and the APU EMERG SHUT DOWN P/BSW on the Refuel/Defuel Panel or automatically, if the APU Fire and Overheat Detection System finds an overtemperature in the APU compartment. On the ground the APU Fire Extinguishing System operates automatically.

Page 134



A334-200/300 GTCP 331−350C

49−61

NON-INHIBITED SHUTDOWN CONDITIONS

OVERSPEED ECB INTERNAL FAILURE (1A) EMERGENCY (FIRE)

UNDERSPEED START ABORTED LOW OIL PRESSURE INLET DOOR NOT FULLY OPEN INHIBITED SHUTDOWN CONDITIONS

LOAD COMPR. REVERSE FLOW HIGH OIL TEMPERATURE

OR

APU GENERATOR HOT

AND

OR

APU SHUTDOWN

CLOGGED OIL FILTER ECB 1B SHUTDOWN MAIN POWER INTERRUPT OVERTEMPERATURE

SHUTDOWN INHIBITION CONDITIONS

N > 95% RPM FROM FLIGHT PHASE 2 TO 9

AND

Page 135 Figure 76

APU Protective Shutdowns


TABLE OF CONTENTS ATA 49 AUXILIARY POWER UNIT . . . . . . . . . . .

1

49−96

APU OIL HEATING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OIL HEATING DESCRIPTION . . . . . . . . . . . . . . . . . . . . . .

54 54

49−30

ENGINE FUEL AND CONTROL . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FUEL CONTROL SYSTEM DESCRIPTION . . . . . . . . . . FUEL DISTRIBUTION SYSTEM DESCRIPTION . . . . . . FUEL SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . .

56 56 58 60 64

49−34

APU FUEL LP WARNING . . . . . . . . . . . . . . . . . . . . . . . . . LOW PRESSURE FUEL WARNING DESCRIPTION . . . LOW PRESSURE FUEL WARNING OPERATION . . . . .

68 68 70

49−50

AIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

72 72

49−51

BLEED AND SURGE AIR . . . . . . . . . . . . . . . . . . . . . . . . . DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BLEED AND SURGE AIR OPERATION . . . . . . . . . . . . . .

74 74 82

49−52

ACCESSORY COOLING . . . . . . . . . . . . . . . . . . . . . . . . . . SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . .

86 86

49−00

GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 2 6

49−10

POWER PLANT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU PRESENTATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 8

49−12

APU MOUNTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SYSTEM PRESENTATION . . . . . . . . . . . . . . . . . . . . . . . . .

12 12

49−20

ENGINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GENERAL LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14 14 16

49−80

EXHAUST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20 20

49−17

POWER PLANT DRAIN SYSTEM . . . . . . . . . . . . . . . . . . DRAIN SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . .

22 22

AIR INTAKE SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AIR INTAKE SYSTEM DESCRIPTION . . . . . . . . . . . . . . . AIR INTAKE SYSTEM OPERATION . . . . . . . . . . . . . . . . .

26 26 28

49−70

OIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . .

30 30 32

INDICATING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ECAM PAGE PRESENTATION . . . . . . . . . . . . . . . . . . . . .

88 88 90

49−71

POWER INDICATING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . .

92 92

OIL STORAGE AND DISTRIBUTION . . . . . . . . . . . . . . . STORAGE SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . DISTRIBUTION SYSTEM DESCRIPTION . . . . . . . . . . . . OIL SERVICING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . DE−OILING SYSTEM OPERATION . . . . . . . . . . . . . . . . .

34 34 36 38 40 46

49−72

TEMPERATURE INDICATING . . . . . . . . . . . . . . . . . . . . . . SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . INDICATING SYSTEM OPERATION . . . . . . . . . . . . . . . .

94 94 96

49−73

ANALYZERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

100

49−40

49−93

OIL INDICATING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOW OIL QUANTITY SWITCH . . . . . . . . . . . . . . . . . . . . .

48 48 50

IGNITION AND STARTING . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STARTING AND IGNITION OPERATION . . . . . . . . . . . . APU SHUTDOWN OPERATION . . . . . . . . . . . . . . . . . . . .

110 110 112 114 120

49−94

LOP AND HOT WARNING . . . . . . . . . . . . . . . . . . . . . . . . . SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . .

52 52

49−60

ENGINE CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

122

49−16

49−90

49−91

Page i

TABLE OF CONTENTS 49−61

APU CONTROL AND MONITORING INTRODUCTION

122

CONTROL AND MONITORING . . . . . . . . . . . . . . . . . . . . SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . ELECTRONIC CONTROL BOX BITE . . . . . . . . . . . . . . . . ELECTRONIC CONTROL BOX . . . . . . . . . . . . . . . . . . . . . SYSTEM INTERFACES . . . . . . . . . . . . . . . . . . . . . . . . . . . APU SHUTDOWNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

124 124 126 128 131 134

Page ii

TABLE OF FIGURES Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32 Figure 33 Figure 34 Figure 35

APU ECS-Supply Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Operating Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Installation and Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Identification Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Mounts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GTCP 331−350 Engine X-Section . . . . . . . . . . . . . . . . . . . . . . . . GTCP 331−350 Engine Cutaway . . . . . . . . . . . . . . . . . . . . . . . . . AGB Mounting Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Drain System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Drain Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air Intake System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air Intake Flap Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil System Component Location (1/2) . . . . . . . . . . . . . . . . . . . . Oil System Component Location (2/2) . . . . . . . . . . . . . . . . . . . . Reservoir Oil Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Pump Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Cooler Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . De-Oiling System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Quantity Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Low Oil Quantity Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOQ-Electrical Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOP/HOT-Warning System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flow Divider Assembly and Fuel Nozzle . . . . . . . . . . . . . . . . . . Fuel System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel Control and Distribution System . . . . . . . . . . . . . . . . . . . .

3 5 7 9 11 13 15 17 18 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 48 49 51 53 55 57 59 61 63 65 67

Figure 36 Figure 37 Figure 38 Figure 39 Figure 40 Figure 41 Figure 42 Figure 43 Figure 44 Figure 45 Figure 46 Figure 47 Figure 48 Figure 49 Figure 50 Figure 51 Figure 52 Figure 53 Figure 54 Figure 55 Figure 56 Figure 57 Figure 58 Figure 59 Figure 60 Figure 61 Figure 62 Figure 63 Figure 64 Figure 65 Figure 66 Figure 67 Figure 68 Figure 69 Figure 70

Low Pressure Fuel Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . LP Fuel Warning Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Load Bleed Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IGV Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Surge Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Surge Air System Components . . . . . . . . . . . . . . . . . . . . . . . . . Air System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air Flow Control Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compartment Cooling Components . . . . . . . . . . . . . . . . . . . . . . DMM Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . System Display & MCDU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU System Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Speed Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EGT Thermocouples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Indicating System Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . ACMS Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MCDU Menu (1/4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MCDU Menu (2/4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MCDU Menu (3/4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MCDU Menu (4/4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ACMS Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Report No. 13 and No. 14 . . . . . . . . . . . . . . . . . . . . . . . . . Starting & Ignition System Design . . . . . . . . . . . . . . . . . . . . . . . 5000VE (Bulk Cargo Compartment) . . . . . . . . . . . . . . . . . . . . . Ignition & Starting Components . . . . . . . . . . . . . . . . . . . . . . . . . Starting and Ignition Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . Starting and Ignition Conditions . . . . . . . . . . . . . . . . . . . . . . . . . Starting and Ignition Schematic . . . . . . . . . . . . . . . . . . . . . . . . . APU-Box 5000 VE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cool Down Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Shutdown Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ECB Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

69 71 73 75 76 77 79 80 81 83 85 87 88 89 91 93 95 97 99 101 103 105 106 107 109 111 112 113 115 116 117 119 120 121 122

Page iii

TABLE OF FIGURES Figure 71 Figure 72 Figure 73 Figure 74 Figure 75 Figure 76

CTL & MON Simplified Diagram . . . . . . . . . . . . . . . . . . . . . . . . . Engine Control Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ECB BITE-Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic Control Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ECB Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APU Protective Shutdowns . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

123 125 127 129 133 135

Page iv

ATA 49 APU.pdf

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