Electrical Instrument Interface Philosophy

PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV

SECTION-IV ELECTRICAL INSTRUMENT INTERFACE PHILOSOPHY

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PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV INDEX SR. NO. 1 2 3 3.1 3.2 3.3 3.4 4 5 6 7 8 9 10

TOPIC INTRODUCTION ABBREVIATIONS POWER INTERFACES INSTRUMENT POWER SUPPLIES LIGHTING SUPPLY/ANALYSER HOUSE SUPPLY PACKAGE UNIT SUPPLY ELECTRICAL HEAT TRACING & LO HEATERS CONTROL CONTROL & MONITORING INTERFACE MANAGEMENT SYSTEMS E&I PLANT DESIGN INTERFACES EARTHING AREA CLASSIFICATION I/O INTERFACES CONTROL DOCUMENT MOTOR OPERATED VALVES (MOV’S) ATTACHMENT ANNEXURE-I, DATABASE

INSTRUMENT/ELECTRICAL

PAGE 3 3 4 4 4 5 5 5 6 8 8 10 10 10

INTERFACE

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PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV 1.0

INTRODUCTION

This Electrical and Instrument interface specification defines the basic division of responsibilities between the two disciplines and involves both specialists engineering as well as design functions. In addition, this specification indicates how to organize the different interfaces.The definition of the split of work and division of responsibilities as outlined shall be followed unless specific circumstances dictate otherwise. These deviations shall be properly recorded and routed as job instructions within the discipline’s task forces for e ach project with approval of OWNER. It is the responsibility of both the E&I lead engineers of BIDDER that the procedures as described in this specification are followed. Interface control documents shall be prepared by the agreed responsible discipline of BIDDER for each interface activity (power supplies, process I/O’s, etc) at the start of the project. These interface control documents shall be maintained, updated and communicated by the agreed responsible discipline in pre-planned intervals during the development of the project. This shall be approved by OWNER before finalization. 2.0

ABBREVIATIONS:

The following abbreviations are used in this specification: AC = DC = DCS = E = EMC = DCS = FO = HV = I&CS = IFC = ILD = IMCS = I/O = IRC = LV = MC = MCC = MOV = PA = P&ID = PMS = SCADA = UPS = VSD =

Alternating Current Direct Current Distributed Control System Electrical Electro Magnetic Compatibility Emergency Shutdown System or Programmable Logic Controller Fiber Optic High Voltage Instruments & Control Systems Interface Cabinet Analog Instrument Loop Diagram Integrated Motor Control System Input / Output Interposing Relay Cabinet (Digital I/O interface) Low Voltage Marshalling Cabinet Motor Control Centre Motor Operated Valve Public Address System Piping & Instrumentation Diagram Power Management System Supervisory Control And Data Acquisition Uninterruptible Power Supply Variable Speed Drive System

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PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV 3.0

POWER INTERFACES

3.1 3.1.1

INSTRUMENT POWER SUPPLIES In general the instrumentation systems and external powered instruments requiring a supply > 50 V AC, BIDDER’s Electrical group shall provide the power supply system dedicated for BIDDER’s I&CS group, including emergency or standby equipment such as generators and UPS systems, power distribution boards and safety switches. However, in this case this shall be tapped off from the main TDI plant control room building UPS ACDB, which is located at @ 1 km away from the proposed locations. The various feeders of 110 V AC UPS supply from UPS ACDB located at main TDI plant control room located 1 km away from the proposed site shall be available in required qty with required amperage. The detail engineering of cable size, cable tray lay out and routing, procurement of cable/cable trays and laying, etc. shall be by BIDDER. Power supply distribution panels at central cabinet room for both system/non-system power shall be the responsibility of BIDDER I & C In case sizing of power supply cable > 2.5 mm2, engineering, design and supply shall be by BIDDER Electrical. The information and requirements for all BIDDER I&CS users for which BIDDER Electrical shall provide the electrical power, shall be communicated by BIDDER I&CS to BIDDER Electrical by means of the “I&CS power supply interfaces list”. Bidder shall ensure 110 V AC -1% & +2% at 50 Hz -3/+1 Hz quality power supply at Central Cabinet room from OWNER’s main TDI project control room UPS/ACDB. Further distribution for DCS shall be by subvendors. However, while designing instrumentation load in instrument system PDBs from the UPS ACDB feeders, care shall be taken to ensure that the max. capacity of each of the mains incomer feeder from UPS to Instrumentation shall be with max current rating of 10% of the UPS capacity in total amperage, at 110 V AC. Also all instrumentation loads shall be catered via two diff. redundant feeders from two different buses of UPS ACDB. For field instrumentation requiring 110 V AC, this shall be 110 V AC -2% & +1% at 50 Hz -3/+1 Hz at field devices (wired from centrally located non-system UPS PDB from central cabinet room only), including all cable drops. The same UPS ACDB bus redundancy philosophy shall be followed for all field instrumentation loads also. However, the complete instrumentation system, including DCS/DCS , Field instrumentation and various package unit systems, shall be designed to run from 90 V AC to 120 V AC at 50 Hz – 3/+1 Hz. UPS power supply (110 V AC, 50 Hz) for whole instrumentation system shall be equipped with half an hour battery back-up source as a minimum, for safe shutdown of plant, in case of total power failure.

3.1.2

3.1.3 3.1.4

3.1.5

3.1.6

3.1.7

3.2 3.2.1

LIGHTING FOR INSTRUMENTS /PANELS/ANAL YSER HOUSES: 230 V A.C. Lighting for Level Gauges and various local panel as well complete lighting of central cabinet room, central control room and central engineering room shall be included in the “E / I&CS power supply

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3.2.2 3.2.3 3.2.4

3.2.5

3.2.6

3.2.7

3.3 3.3.1

3.3.2

3.4 3.4.1

interfaces list” with a reference to the level gauge tag number for which the lighting fixture is required. This shall be by BIDDER Electrical. For level gauge, supporting bracket (part of level gauge assembly) and fixture specification is the responsibility of BIDDER Electrical. Engineering, design and supply by BIDDER Electrical Distribution boards, if applicable, shall be located on the outside of the analyzer house and shall be suitable for hazardous area classification of the plant. However for each analyser, the individual 110 V AC UPS supply cables (in required sizes) will be laid from central cabinet room located non-system UPS PDB by BIDDER I&C. Instead of laying 3 core power cable from central control room located non-system UPS PDB to each analyser, there shall be 2 core cable for each analyser. The final safety earth cable in redundant loop format from each analyser shall be brought to a common safety earth pit located near control room for instrumentation safety earth purpose. These earthing cables from each analyser houses, local panels, etc. to control room safety earth pits shall be redundant. No UPS supply shall be provided to analyzer house, local panel for any of the instruments by BIDDER Electrical, directly from MCC. These shall be laid from the various UPS non-system PDB panels, located at central cabinet room by BIDDER I &C, as per requirement. For Electric motor operated valves, position switches shall be connected to DCS via Electrical / Instrument interface panel (IRC) via interposing relays only. Hence from MOV all the signals including torque switches, limit switches, etc. shall be wired to MCC and from MCC, the required onoff indication limit switches signals shall be wired to instrumentation system for indication/control/logic purpose to I&C. Hence it is the responsibility of BIDDER Electrical including supply of cables, glands, terminations, etc. from field MOV to MCC and MCC to electrical/instrument interface cabinets. Power supply to these MOV’s is also the responsibility of BIDDER Electrical. Power suppl y to PACKAGE UNITS This shall be provided by BIDDER I &C from the central cabinet room located non-system UPS PDB panel located at only one location to each of the package units in the field. Further sub distribution shall be carried out inside the package unit by package unit vendor. 230 V A.C. power supply required for non-instrument purpose shall be provided by BIDDER Electrical to all package units, directly from MCC in panel shed lighting, shelter illumination, etc. However, local instrument panel inside illumination shall be by BIDDER I&C, which will be wired form central cabinet room located 230 V AC utility PDBs by BIDDER I&C. ELECTRIC HEAT TRACING & LO HEATERs Electrical heat tracing power supply shall be provided by BIDDER electrical from MCC. This refers to process pipe line/equipment heat

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3.4.2

3.4.3

3.4.4

4.0 4.1

4.2

4.3

4.4

4.5

tracing, etc. For analyser sample tube heat tracing, etc., it is BIDDER I&C responsibility to provide 110 V AC UPS supply for sample heat tracing line from centrally located non-system UPS PDB. Various Lube oil heater circuits, in general, shall be controlled by DCS by BIDDER I&C. For the purpose, there shall be separate and dedicated Lube oil level and temperature transmitters installed on the LO tank. LO heater shall automatically start and stop from DCS interlock/Logic on Low LO temperature and High LO temperature/ Low LO level, respectively, via two separate DCS DO for auto start and process trip, via interposing relays in IRC driven by DCS Logic. Additionally, there shall be manual start and stop facilities from DCS graphic as a soft target. This soft target will actuate a DCS DO, which will be wired via IRC panel located interposing relays to MCC for start and stop of LO heater manually. CONTROL AND MONITORING INTERFACES The E&I interface point for process and safeguarding systems measurement, monitoring, control and protection I/O’s is the IRC and/or the IFC which shall be located in the central cabinet / marshalling room within I&C premises. The IFC will be used for analogue signals (e.g. VSDS). From this panel, all 4-20 ma signals shall be wired to relevant I&C DCS marshalling panels. Since there shall not be any RTD or T/C type input cards in DCS/DCS , all Motor bearing/winding related trips shall be realized by BIDDER Electrical via their MCC SCADA. Only the redundant software communication link from MCC SCADA to DCS shall be made available to I&C for making all such RTD and T/C real time indications/alarms available to DCS operator on graphics. Hence there shall not be any motor bearing/winding trip related hard wired signal exchange between DCS and DCS and DCS to MCC. Engineering, procurement and laying of cables and all termination from MCC/Field Motors to MCC SCADA, logic realization in SCADA with sequence of event reports, etc. shall be carried out by BIDDER Electrical for all these signals. All potential free/dry contacts for pump / motor running indications, MOV open/close limit switches, etc. from MCC/SWB or VSD panels from electrical shall be wired to IRC via interposing relays and by BIDDER Electrical, including design, procurement and installation/laying of various cables between MCC/SWB/VSD panels to IRC. IRC panel shall be of two types, i.e. DI IRC, which will accept all input signals to DCS wired from MCC via interposing relays and the DO IRC which will provide various pot free digital output contact from DCS to MCC via interposing relays. The relays in IRC for interposing purpose shall be by BIDDER I&C. All RUN signals shall be hard wired between MCC and DCS. The redundant software communication link between SCADA and DCS shall be used to monitor various other signals like motor trouble, motor fault, ready-to-start signals which are not used in control or interlock/logic by I&C in DCS. If

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4.6

4.7

4.8

4.9

4.10

4.11

4.12

4.13

any of these signals is used in control, interlock / logic or decision making purpose at DCS, the same shall also be hard wired from MCC to DCS. All Digital output commands from I&C DCS systems for various purpose like Motor Trip/Auto-Manual Command( if used), Emergency Stop, etc. shall be wired from respective DSC panels to IRC via interposing relays by BIDDER I & C. All Auto/Manual switches shall be configured in DCS as soft targets on DCS graphic accessible to operator with dynamic status. The Auto/Manual logic shall be realized in DCS along with other process parameters and/or running pump/motor run signals. The auto start commands generated from DCS DO shall be hardwired to MCC via interposing relays located in IRC. Hence no field LCS by BIDDER Electrical shall be with A/M switches. The normally energized status of relays shall be maintained in normal condition and when relay gets deenergized, auto start command shall be sent to MCC from DCS. All Digital output commands from interposing relays meant for Electrical MCC/SWB/VSD panels, etc. from IRC shall be accommodated in IRC. They shall be wired from IRC panel to MCC/SWB/VSD panel by BIDDER Electrical. All cables shall be designed, procured and laid by BIDDER Electrical. The normal energized status of DO relays/Process trip will keep the pump/unit / section in running condition. On actuation of trip, the de-energized status of relay shall trip the pump/motor. All IRC/IFC panels shall be of standard RITTAL make panels with 1200mm (W) x 800mm (D) x 2100 mm(H) size, with RAL7032 color and shall be located at central cabinet room within the premises of I & C. It is the responsibility of BIDDER I & C All cabling between the IRC/IFC and MCC/SWB or other electrical control panels (i.e. VSDS panels), field Motors, etc. is the responsibility of BIDDER Electrical. The multi pair cables shall be separate for DI and DO exchange between MCC and DCS. The measurement of power factor, frequency, speed, power consumption and other typical electrical signals to be processed / handled in instrumentation systems is the responsibility of the BIDDER Electrical discipline. I&CS will be responsible for incorporation of these measurements into their system(s) from the interface point (IFC) to respective DCS /DCS panel. Measurements shall preferably be presented by BIDDER Electrical as isolated analogue signals of 4-20 mA DC, or this may be via Electrical SCADA redundant software communication link to central DCS, if such information are meant only for information purpose in the DCS. The monitoring and alarms annunciating associated with motors, switchgear, transformers and any other electrical equipment, which are to be, annunciated on instrument panels and/or in I&CS are the responsibility of BIDDER Electrical. BIDDER I&CS will be responsible for incorporation of these alarms into their system(s) from the interface point (IRC) or via software communication link between MCC SCADA and DCS. BIDDER I&CS will be responsible for the detailed control, alarm, safeguarding requirements as shown on the P&ID's and passing all

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4.14 4.15

4.16

4.17

4.18

5.0

signals required for electrical control to the interface point as detailed for each project. BIDDER I&CS shall include the tag number on the interface document. Instrument Loop Diagram shall show the complete loop inclusive a reference drawing number with respect to the electrical wiring up to the point of interface, i.e. IRC/IFC. For all pumps/motors, emergency stop command, BIDDER I&C shall use a Mushroom Push Button with key lock, installed on Operator console. This buttons shall operate a 24 V DC interposing relay located in IRC. The potential free contact from these relays shall be wired to relevant MCC/SWB/Motors at Electrical Substation by BIDDER Electrical for stopping those motors. The other spare contact of such relay from IRC shall be wired by BIDDER I&C as a feed back to DCS as digital inputs to their system for registration of pressing of push buttons with alarms on DCS and DCS graphics. This emergency push buttons shall be in addition to any Trip/Auto stop contact generated from DCS interlock from I&C System. In this case the two contacts (Em. Stop and process trip) shall be wired to MCC/SWB/Motors by BIDDER Electrical in their protection circuitry in series. In genral, remote start from Operator Console from Central Control room is not envisaged for any Motor/Equipments. These shall not be provided, unless process group requires such facilities for a few of very critical equipments, which will be decided during detail engineering.

MANAGEMENT SYSTEMS Motor management and power management system ("intelligent" or “smart” switch gear) are the responsibility of BIDDER Electrical. Since these systems will be integrated with Distributed and/or Other control systems (i.e. DCS) via redundant software communication link, close coordination and exchange of data and protocol agreement shall be established between the BIDDER E&I. The SCADA being designed, procured and implemented by BIDDER Electrical shall have the following minimum hardware / functionality for its interconnectivity with central DCS. a.

b. c. d. e.

An isolated 2 Wire RS485 Serial Communication Link as an Interface ( Modem , over RS232C or current loop interfaces are not acceptable) A proper communication media like twisted pair, screened/shielded cable laid between Electrical and Instrument cabinet room. MODBUS RTU protocol with complete memory map, configuration details, etc. The scan time shall be better than 2 to 3 seconds for transferring all parameters of SCADA to DCS. Electrical System/MCC SCADA shall be integrated with centralized DCS. This shall be integrated with centralized DCS located at

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f.

central control room with one way information exchange purpose in DCS (from MCC to DCS). The communication link between SCADA and DCS shall be over redundant serial RS485 interface with MODBUS protocol. There shall not be daisy chain configuration on RS485 serial link between SCADA and DCS. One SCADA shall be connected with one dedicated RS485 dual redundant serial link with DCS. No other RS485 devices shall be clubbed on this serial link. The DCS, being a master time keeper on the entire plant wide network for uniform time stampings, the MCC SCADA shall also be synchronized with DCS time via NTP and GPS system via suitable interface with hardware firewall.

6.0

E&I PLANT DESIGN INTERFACES

6.1

CABLE TRAY/LADDER / TRENCH ROUTING

6.1.1

6.1.2

Each discipline of BIDDER is responsible to provide the required input of the cable tray / ladder routing. The coordination within various other department of BIDDER like Piping, Civil, Structural and Pipe-support with respect to main tray/ladder routing (e.g. space management, road crossings etc.) will be done by BIDDER Electrical for both disciplines. Underground/trench cables routing is not allowed. An overall tray/ladder drawing (study) shall be prepared by BIDDER Electrical, with input from I&CS and will clearly indicating the following: a. b. c.

6.1.3

6.1.4

Tray/ladder routes, including termination points of runs, space and segregation requirements including spare capacity Elevations (for trays), Road crossings where applicable Segregation required between I&CS and Electrical cable tray/ladder.

In general a. All high voltage cables carrying Electrical control voltage signal/current shall be routed in separate ducts/tray b. All low voltage instrument signals like Run indication ( carrying 24 or 5 V DC interrogation voltage from DCS), low voltage electrical signals like VSD 4-20 ma input/outputs, etc. shall be laid in a separate tray/duct c. All communication cables, PA system audio cables, telephone voice cables, Fiber optic cables shall be routed through separate duct/trays All the ducts/cable trays between instrument central cabinet room and electrical substation/MCC room shall be sized in such a way to have 50% spare capacity for future use. All main cable ducts between MCC and Central cabinet room shall be min. 5 MM thick GI MOC duct with 3 mm thick SS304 MOC closed cover and all trays shall be either ladder or perforated tray of aluminum MOC.

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PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV 6.1.5

7.0

All MCC cables from MCC to central cabinet room shall be brought inside via separate dedicated MCT frames the MCT blocks which will be identified as an Electrical MCT. The low voltage and high voltage MCT block segregation shall be maintained via separate entries of MCT blocks. EARTHING

7.1

The main earthing, involving static earthing, protective earthing, lightning protection and instrument earthing systems are the responsibility of BIDDER Electrical.

7.2

The provision of earthing facilities on and within instrument equipment, instruments and any specific shielding requirements are the responsibility of BIDDER I&CS. However necessary earth pits shall be provided by BIDDER Electrical as per the requirement of BIDDER I & C. For the purpose BIDDER I&CS will provide an instrument earthing philosophy and relevant typical earthing block d iagram to BIDDER Electrical.

8.0 8.1

9.0 9.1

10.0 10.1

10.2

AREA CLASSIFICATION This is the responsibility of the BIDDER Electrical discipline in close coordination with Process. Area classification schedules, layouts and if required sections will be prepared, from which both BIDDER E and I&CS disciplines shall obtain the material selection requirements to ensure suitability in the specific areas. However, as far as instrumentation is concerned, the overall concept of all field instrumentation execution shall be for general purpose instrumentation without any explosion protection but with weather protection to IP65 as a minimum. I/O INTERFACES CONTROL DOCUMENT A common database will be filled with information from BIDDER I&CS, BIDDER Electrical and BIDDER Process Group, based on various process requirement, facilities and interlock/control necessity. A consolidated format is attached herewith as Annexure-1. Moto ri zed Valves / MOVs: To the extent possible, the MOV shall not be used in the plant. However, if the requirement can not be avoided, it shall be the responsibility of BIDDER Electrical for all type of procurement, erection, commissioning, power supply provision, laying of necessary cables from Substation and final operation, testing and maintenance of the same shall be carried out by BIDDER Electrical. The body/bonnet and trim MOC and other specifications/ construction of MOV shall be as per mechanical specification of this ITB. At few locations, if MOV is equipped with various position sensors, these shall be SNAP action type micro switches. These shall be wired from field to MCC by BIDDER Electrical and from MCC, via Digital Input interposing

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PAC PROJECT INSTRUMENTATION SPECIFICATION SECTION-IV relays located in IRC, the same shall be either given to DCS, if used in interlock/logic. If these switches are used only for indication purpose in DCS, the same shall be brought to DCS via MCC SCADA over software communication link.

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Electrical Instrument Interface Philosophy

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