d257272-1200-fdd-002-r1.pdf

www.nov.com

FIN

AL

DO

CU

MEN

TATI

ON

PA

CK

AG

E

SC

R T

echn

ical

Man

ual

Engi

neer

ing

& M

arin

e Se

rvic

es (P

TE) L

TD.

M

obile

Mod

ular

Wor

kove

rUni

t–1st

MM

WU

Rig/Plant Mobile Modular Workover Unit

1st MMWU Customer

Engineering & Marine Services (PTE) LTD.

Project Manager

N/A Purchase Order Number

J301270002

National Oilwell Varco

10000 Richmond Ave.

Houston, Texas 77042

P.O. Box 4888

Houston, Texas 77210

USA

Phone: 713-346-7500

FAX: 713-435-2195

Document Number

D257272-1200-FDD-002

Rev

01

SCR/Generator Control

Final Documentation Package – Operations and Maintenance Manual PO Number: J301270002 Engineering & Marine Services (PTE) Ltd. – Mobile Modular Workover Unit – 1st MMWU Page: ii of ii

www.nov.com

Table of Contents This manual may consist of several volumes, chapters and sections and is housed in a number of different binders as necessary to adequately document the equipment presented. Each binder or volume is provided with a “Table of Contents”.

FINAL DOCUMENTATION PACKAGE OPERATIONS AND MAINTENANCE MANUAL Engineering & Marine Services (PTE) Ltd. Mobile Modular Workover Unit – 1st MMWU

SCR Technical Manual

Description Chapter - Section

Introduction Title Page ......................................................... Front Matter

Table of Contents............................................................... ii

SCR/Generator Control Package ...................................................................................... 1.0 SCR Drive System ................................................................................................................1.1

Generator Unit.......................................................................................................................1.2

SCR Unit ...............................................................................................................................1.3

Driller’s Console ....................................................................................................................1.4

Transformer Feeder Unit .......................................................................................................1.5

Motor Control Center.............................................................................................................1.6

Drawworks Braking ...............................................................................................................1.7

Unique Devices .....................................................................................................................1.8

Spare Parts List.....................................................................................................................1.9

SCR/Gen Test Procedure ...................................................................................................1.10

Certificate of Compliance ....................................................................................................1.11

FINAL DOCUMENTATION PACKAGE Engineering & Marine Services (PTE) LTD. SCR/Generator Control

www.nov.com

Chapter 1.0 SCR/Generator Control

Package

www.nov.com

REFERENCE

7272 C00,01,02,04 REFERENCE DESCRIPTION

Engineering & Marine Services (PTE) LTD. This document contains proprietary and confidential information which belongs to National Oilwell Varco; it is loaned for limited purposes only and remains the property of National Oilwell Varco. Reproduction, in whole or in part; or use of this design or distribution of this information to others is not permitted without the express written consent of National Oilwell Varco. This document is to be returned to National Oilwell Varco upon request and in any event upon completion of the use for which it was loaned. © National Oilwell Varco

National Oilwell Varco 11000 Corporate Center Dr Houston, TX 77041 Phone + 281 854 0400 Fax + 281 854 0607

DOCUMENT NUMBER

D257272-1200-TOC-001 REV

01

Table of Contents

SCR / Generator Control Unit


www.nov.com

Section 1.1 SCR Drive System

www.nov.com

RIG/PLANT

Mobile Modular Work Over Unit-1stADDITIONAL CODE

SDRL CODE

TOTAL PGS 44

REMARKS MAIN TAG NUMBER

DISCIPLINE

CLIENT PO NUMBER GMK710301D CLIENT DOCUMENT NUMBER

REFERENCE

20605-44 REFERENCE DESCRIPTION

Engineering & Marine Services (PTE) LTD This document contains proprietary and confidential information which belongs to National Oilwell Varco; it is loaned for limited purposes only and remains the property of National Oilwell Varco. Reproduction, in whole or in part; or use of this design or distribution of this information to others is not permitted without the express written consent of National Oilwell Varco. This document is to be returned to National Oilwell Varco upon request and in any event upon completion of the use for which it was loaned. © National Oilwell Varco

National-Oilwell Varco 11000 Corporate Centre Dr Houston, TX 77041 USA Phone +1 281 854 0400 Fax +1 281 854 0607

DOCUMENT NUMBER

D257272-1200-MAN-001 REV

01

Technical Manual

50 Hz SCR Drive System

Note

Click mouse on item of interest in the Table of Contents - it will LINK you to more information


www.nov.com

Section 1.2 Generator Unit

www.nov.com

RIG/PLANT

Mobile Modular Work Over Unit-1st ADDITIONAL CODE

SDRL CODE

TOTAL PGS 57


DISCIPLINE


REFERENCE



National-Oilwell Varco 11000 Corporate Centre Drive Houston, Texas 77041 USA Phone +1 281 854 0400 Fax +1 281 854 0607

DOCUMENT NUMBER

D257272-1200-MAN-002 REV

01

Technical Manual

Generator Unit

Document number D257272-1200-MAN-002 Revision 01 Page 2

www.nov.com 24 HOUR SERVICE (281) 569-3050

REVISION HISTORY

01 17.12.2008 Issued For Information BKF NEG KM Rev Date (dd.mm.yyyy) Reason for issue Prepared Checked Approved

CHANGE DESCRIPTION

Revision Change Description 01 Issued For Information



TABLE OF CONTENTS 1 GENERATOR UNIT.......................................................................................................... 4

1.1 Operation Description ............................................................................................. 4

1.2 Specifications ......................................................................................................... 6

2 MAINTENANCE................................................................................................................ 8

2.1 Testing.................................................................................................................... 8

2.2 Servicing................................................................................................................. 8

2.3 Theory of Operation.............................................................................................. 23

2.4 Power Limit Circuit................................................................................................ 43

2.5 AC Ground Fault Detection Circuit........................................................................ 46

2.6 TROUBLESHOOTING.......................................................................................... 46

3 HI-LINE OPERATION..................................................................................................... 51

4 REMOVAL & REPAIR .................................................................................................... 54

4.1 Model 1000........................................................................................................... 54

4.2 Model 1400........................................................................................................... 55

4.3 Model 1861........................................................................................................... 56

Note




1 GENERAT OR UNIT

1.1 Operation Description The Generator Unit controls the engine/ generator set to develop a constant AC supply. The output of several generators are fed to a common AC bus (refer to Figure 2-1). Each Generator Unit's AC Control Module has an electronic engine governor; a voltage regulator and a circuit breaker (refer to Figure 2-2). The circuit breaker is interlocked with a Protection circuit which automatically trips the breaker for malfunctions such as over-current, over-voltage, under/over-frequency and reverses power. In addition, a Synchronization Panel is provided with each system to match individual generator frequency and voltage to the bus frequency and voltage.

Figure 2-1. Generator Unit Functional Diagram



Figure 2-2 AC Control Module Controls and Indicators



1.2 Specifications

1.2.1 Electrical Table 2-1 lists the electrical specifications of the AC Control Module.

1.2.2 Mechanical They are mounted in a sheet steel cubicle. Dimensions vary from model to model. A typical Generator Cubicle is 90" H. x 36" D. x 24" W. and weighs ≈2,000 pounds.



Table 2-1. Electrical Specifications

Many of the electronic circuits associated with generator control are housed in the AC Control Module. The AC Control Module is constructed from 14-gauge steel, and has its own heatsink. AC CONTROL MODULE SPECIFICATIONS Size 12" High x 12" Deep x 4" Wide Weight 25 pounds

ELECTRICAL POWER

AC Supply Three phase, 50 Hz. 600 VAC.

GENERATOR CIRCUIT BREAKER

Overcurrent The circuit breaker is preset to trip under the following conditions: Amperes required to trip depends on generator KVA rating.

Overvoltage ≈ 1.16 times normal bus voltage, 100 mS

delay. Overfrequency 55 - 56 Hz. Underfrequency 42 Hz. Reverse Power Usually -7% to -10% of rated KW.

ENGINE GOVERNOR

Regulation 0.5 Hz, steady state. Response Time One Second. Load Unbalance 5% rated load.

GENERATOR VOLTAGE REGULATOR Regulation 3% maximum. Response Time One Second. Load Unbalance 10%, no load to full load of rated KVARs. Exciter Power 100/200 VDC, 12 Amps maximum. KVAs

are distributed among generators by reactive droop compensation.



2 MAINTENANCE This section contains testing and servicing information to assure proper operation of the Generator Unit. TROUBLESHOOTING (later in this chapter) has an explanation of the various Generator Unit circuits. REMOVAL AND REPAIR (also later in this chapter) identifies the various generator assemblies.

2.1 Testing Perform the functional tests given in Tables 2-2 through 2-6 after repairing/replacing any assembly. Perform the Reverse Power Trip and Engine Mechanical Over-speed tests listed in Table 2-4 once a month.

SERIOUS DAMAGE TO THE ENGINE CAN RESULT IF REVERSE POWER AND ENGINE OVERSPEED FUNCTIONS DO NOT FUNCTION PROPERLY.

These are the tables and their titles: 2-2 Engine/Generator Unit Functional Test 2-3 AC Module Functional Tests 2-4 Protection Circuit Functional Test 2-5 Calibration Procedure for Woodward EG-3P and EG-10P Actuators 2-6 Calibration Procedure for Woodward EG-B 10P Actuators Used on EMD Engines The TEST switch allows a quick check of the systems vital signals. The TEST switch and the TEST METER are color coded. For example, if the TEST switch is set to the yellow BREAKER TRIP VOLTAGE position, normal condition is indicated by the TEST METER needle deflecting to the yellow.

2.2 Servicing Servicing consists of oil change and calibration procedure of the throttle actuator terminal shaft.

2.2.1 Oil Change The Woodward EG-3P and EG-10P Actuators receive oil from the engine oil supply, so regular engine oil change intervals are sufficient. The Woodward EG-B 10P Actuator has its own oil supply. Change it every six months under favorable operating conditions. The oil sump holds one U.S. Quart. Refer to the following and the manufacturer's literature.



The main difference between these models: the EG-B has a Ball Speed governor and self-contained oil supply. Changing the Oil in the EG-B 10P 1. To drain the oil, unscrew the Drain Cock located in the lower left-hand corner of the front panel. 2. To flush the actuator, add one quart of diesel fuel or kerosene through the Oil Cup located on the top. Run the engine speed up and down by switching the Engine Control switch between IDLE and RUN. After a few minutes, shut the engine off and drain the fluid. Repeat flushing until the Drain Cock fluid is clean. 3. Drain all the fluid and screw in the Drain Cock. Fill the actuator with one quart of the recommended lubricating oil. Woodward recommends Mobil 1.

IF THE OIL IN THE EG-B 10P ACTUATOR IS NOT CHANGED REGULARLY, IT WILL BECOME CLOGGED WITH GUM AND FAIL.

2.2.2 TERMINAL SHAFT CALIBRATION Calibrate all engine actuators if KW load sharing at full load exceeds 10% (see Table 2-5).



Table 2-2. Engine/Generator Unit Functional Test

ACTION RESULTS PRELIMINARY A. Open all the Generat or unit fuses, with

the engine shut down.

A. There are no measur able results from

this step. THROTTLE CHECK A. Disconnect Throttle (+) (TB11-1) and

Throttle (-) (TB11-2) (this is TB4 or TB9 in older systems).

Refer to your s ystem prints to determine the terminal strip connections for the Throttle and Exciter.

B. Measure the resistance between the leads to the Throttle to check for open or short circuit conditions.

C. Measure the resistance between each throttle actuator lead and ground.

D. Reconnect the throttle leads.

A. There are no meas urable res ults from

this step. B. The resistance should be ≈30 to 36Ω.

C. The reading should be an open circuit reading ( ∞Ω) unless the cable is grounded.

D. There are no meas urable res ults from this step.

EXCITER CHECK A. Disconnect the Excit er (+) wire from

TB11-7 and the Exc iter (-) wire from TB11-8 (this is T B4 or TB9 in older systems).

Refer to your system prints to determine the terminal strip connections for the Throttle and Exciter.

B. Measure the resistance between the leads to the Generator Exc iter to chec k for open or short circuit conditions.

C. Check the resistance from each exc iter lead to ground.

D. Reconnect the Exciter leads.

A. There are no measur able results from

this step. B. The resistance should be 3 to 20 Ω (this

depends on generator model). C. The resistance should be ∞Ω after

TB11-8 in the genera tor switch gear is disconnected.

D. There are no measur able results from this step.



ACTION RESULTS CONTROL CIRCUIT TEST A. Set the E NGINE CONTROL SWITCH to

IDLE.

B. Start the engine and run it at ≈2/3 speed.

C. Using the oscilloscope, check the phas e rotation at the generator stabs.

Figure 2-3. Phase A

Figure 2-5. Phase C

A. There are no measur able results from this

step.

B. If the system incorporates HOC (Hands Off Cranking), the HOC batteries supply power to the AC Control Module (it is not necessary to manually control the engine actuator).

C. The A phase voltage peak (see Figure 2-3) occurs 120° before the B (see Figure 2-4). The B phase voltage peak occurs 120° before the C (see Figure 2-5). Figure 2-6 shows phase rotation.

Figure 2-4. Phase B

Figure 2-6. Phase Rotation

Table 2-2. Engine/Generator Unit Functional Test (Continued)



ACTION RESULTS

CONTROL CIRCUIT TEST (CONCLUDED) D. Close fuses F30, F3 1, F32, F35, F36,

and F37 on the input of the AC Regulator Transformer.

On most models, these fuses will be F30 F31, F32, F33, F34, and F35.

E. Check the phase rotation at the AC Control Module pins 512 through 517.

D. There are no measurable result s from thi s

step.

E. There are six phase voltages. VAB (pin 512) should have a waveform which is inverse of VBA (pin 513). The inverse relationship also exists between VBC (pin 514) and VCB (pin 515), and VCA (pin 516) and VAC (pin 517).

VOLTAGE REGULATOR TEST A. Disconnect wires Gate A+ (Pin 504) and

Gate A- (Pin 505). B. Close the Exciter fuses.

Exciter fuse numbers depend on model of sy stem (check y our generator control schematic in your drawing package). The Exciter fuses for the 1400 system are F39 & F40.

C. Observe the generator VOLTMETER.

D. Monitor the signals at Pins 512 through

517. E. If the results indicated in Steps C and D

occur, reconnect the Gate A+ and Gate A- wires.

F. Set the VOLTS ADJUST control to give

a 50% indication on the generator VOLTMETER.

A. There are no measurable result s from thi s

step.

B. There are no measurable result s from thi s step.

C. The voltage should rise to ≥200 VAC, and fall cyclically as K1 (the build- up relay) picks up and drops out.

D. These signals should also rise and drop.

E. There are no measurable result s from thi s step.

F. The VOLTMETER will indicate 300 to 450 VAC.




ACTION RESULTS

ENGINE GOVERNOR TEST A. Determine the model of your Throttle Actuator. If

it is a Wo odward Mo del EG-B 10P, perform Steps B through D. If it is a Wood ward Model EG-3P or EG-10P, skip to Step E.

B. Set the SPEED DROOP control to 0 (Zero).

C. Set the LOAD LIMIT control to MAXIMUM FUEL.

D. Move the SPEED ADJUST knob on actuator to maximum CW rotation. This represents a generator frequency of approximately 54 Hz. Slowly rotate the SPEED ADJUST knob on the actuator CCW until the engine just begins to slow down.

SLOWING DOWN THE ENGINE BELOW THIS RPM MAY INTERFERE WITH THE AC MODULE’S ABILITY TO PROPERLY CONTROL THE OPERATION OF THE ENGINE.

E. Set the SPEED ADJ UST control t o somewhat less than 50% on it's scale indication.

F. Turn the ENGINE CONTROL switch to IDLE and start the engine.

G. Allow the engine to warm-up for 15 minutes.

H. Turn the ENGINE CONTROL switch to RUN.

I. Fine tune the VOLTAGE ADJUST and SPEED ADJUST knobs to achieve 600 VAC at 50 Hz.

J. Turn the ENGINE CONTROL switch to IDLE.

K. Turn the ENGINE CONTROL switch the engine back to RUN.

A. There are no measurable results from this step.

Steps B through F set the various controls of the Throttle Actuator. Woodward Models EG-3P and EG-10P do not have these controls and, therefore, do not require these steps to be performed.

B. There are no measurable results from this step.

C. There are no measurable results from this step.

D. There are no measurable results from this step. E. There are no measurable results from this step. F. There are no measurable results from this step. G. There are no measurable results from this step. H. The generator voltage and frequency should

increase as the ENGINE CONTROL switch is moved from IDLE to RUN.

I. The Generator VOLTMETER will indicate 600 VAC. The FREQUENCY meter will indicate 50 Hz.

J. The generator voltage and frequency should decrease to Idle values.

K. The generator frequency should stabilize at 50 Hz within two overshoots.




ACTION RESULTS SYNCHRONIZATION CIRCUIT TEST A. Connect one engine/ generator to the Main

AC Bus.

This test only needs to be performed if components in the synchronizing circuit have been changed or if a problem is encountered in synchronization.

B. Proceed to a seco nd/subsequent generator,

and following the st eps indicated in the previous s ections of the test, adjust it s controls to develop 600 VAC at 48 Hz.

C. Connect an AC Volt meter, switched to read 600 VAC, between the oncoming generator's stab A phas e and the Main AC Bus stab A phase.

D. Adjust the generator’s frequency to 50 Hz, so that it slowly goes in and out of synchronization with the Main AC Bus. Observe the Volt meter, the SYNCHROSCOPE, and SYNC LIGHTS.

E. Close the oncoming generator’s circuit breaker when sync occurs.

Synchronization between the Main AC Bus and the oncoming generator has occurred when the needle of the SYNCHROSCOPE is points vertically, the SYNC LIGHTS are off, and a Simpson Model 250 (or equivalent) Volt Ohm Meter (VOM) connected to the top and bottom of the Main AC Circuit Breaker indicates minimum voltage.

A. There are no measurab le resu lts from this step.

GENERATOR CIRCUIT BREAKERS WILL NOT CLOSE UNTIL SYNCHRONIZED WITH THE MAIN AC BUS. DO NOT CLOSE ANOTHER GENERATOR’S CIRCUIT BREAKER UNTIL THE SYNCHROSCOPE AND SYNC LIGHTS HAVE BEEN CHECKED FOR PROPER OPERATION.

B. The pointer of the SYNCHROSCOPE will turn counterclockwise. The SYNC LIGHTS will be dimly illuminated.

C. There are no measurab le resu lts from this step.

D. The pointe r of the SYNCHROSCOPE will turn clo ckwise o r co unterclockwise. The SYNC LI GHTS will alternat ely di m and brighten.

E. The generator’s circuit breaker will not close if proper synchronization has not been achieved. The KVAR meters of all generators on line should each read the same value.




ACTION RESULTS

LOAD DISTRIBUTION TEST Five separate tests comprise the Load Distribution Test: • KVAR Sharing Test. • KW Sharing Test. • Master/Slave Sharing Test. • Engine/Generator Idle-Run Test. • Load Testing Engine/Generator Test. KVAR Sharing Test A. Balance the KVARs by using the VOLTS

ADJUST knob of the Gener ator Control Cubicle that has the lowest reading KVAR.

KW Sharing Test A. Connect all engine/generator sets to the

Main AC Bus.

B. Make assignments to provide ≈60% KW Load.

Master/Slave Sharing Test A. Connect all the system generators to the

Main AC Bus. The KW and KVAR reading of each connected engine/generator set should be about the same.

B. Disconnect Generator 1 from the Main AC Bus.

C. Disconnect Generator 2 from the Main AC Bus.

D. Reconnect all generators to the Main AC Bus.

A. Watch the KW and KVAR readings while the system load is changing. The generator readings should be about the same.


B. The KW METERS of all engine/generators should read the same and track together as the KW Load varies.

A. Observe that only the master generator

SPEED ADJUST dial has an e ffect on the speed of all the engines on the lines. Verify that the lowest numbe red onlin e generator controls all other online generators.

B. Verify that with Gener ator 1 off the Main AC Bus, Generator 2 controls all other connected generators

C. Verify that with Gener ators 1 and 2 off the Main AC Bus, Generator 3 controls all other connected generators.

D. There are no measurable results from this step.



Table 2-2. Engine/Generator Unit Functional Test (Concluded)

ACTION RESULTS

LOAD DISTRIBUTION TEST (Concluded) Engine/Generator Idle-Run Test A. Start an engine/genera tor set and run it at

IDLE. Follow the recommended warm up time specified by the engine/generator set manufacturer.

B. Put the ENGINE CONTROL switch to RUN and adjust the SPEED ADJUST potentiometer to 50 Hz.

C. Put the ENGINE CONTROL switch to IDLE. D. Put the ENGINE CONTROL switch to RUN. Load Testing Engine/Generator Test A. After performing the Engine/Generator Idle-

Run test, connect the engine/generator to the Main AC Bus.

B. Connect a load (such as a tank of salt water) to the Main AC Bus.


B. The generator voltage and frequency should increase as the engine goes from IDLE to RUN speed.

C. The generator voltage and frequency should decrease to the idle value.

D. The generator frequency should stabilize a t 50 Hz. within two overshoots.


B. Observe the Engine/Generator's KW METER and compare the reading to the Engine/Generator's rated KW capacity.



Table 2-3. AC Control Module Functional Test

ACTION RESULTS

PRELIMINARY

A. Inspect the AC Control Module wiring harness for incorrect and/or loos e connections.

B. Turn on the Generator unit.

A. Fix any incorrect or loose connections.

B. The Generator RUN light and the AC Control Module front panel POWER ON light will illuminate.

POWER SUPPLY CHECK A. Measure the voltage at the following points:

Terminal Pin 502 Terminal Pin 503 Terminal Pin 507 Terminal Pin 508 Terminal Pin 546

Auxiliary Board Pin 24

A. The voltage should be:

+16 VDC -16 VDC

-160 VDC +160 VDC

+11 VDC -11 VDC

FREQUENCY DEMODULATOR TEST

The Frequency Demodulator Circuit is used to develop a speed feedback signal. This signal is necessary for diesel engine speed regulation. The six AC phases from the AC Regulator Transformer are processed by the Demodulator Circuit into the Frequency Demodulator Output Waveform. The Frequency Demodulator Output Waveform is converted by the AC Control Module circuit into the Frequency Feedback Signal which can be measured at TP19 of the AC Control Module. The Frequency Feedback Signal will be -2.5 VDC at the system's proper operating frequency.

The appearance of the Frequency Demodulator Output Waveform w ill NOT appear the same if different oscilloscope adjustments are used. Therefore, use the suggested settings for viewing the waveform.

Field calibration of this circuit is difficult and not recommended.



Table 2-3. AC Control Module Functional Test (Continued) ACTION RESULTS

FREQUENCY DE MODULATOR TE ST (CONCLUDED)

A. Check TP5 for the Frequency Demodulator Output Waveform in the Unit Under Test.

If desired, you can compare the waveform of the Unit Under Test with the waveform of a known fully functional unit.

A. The wavef orm should be lik e the one shown in Figure 2-7.

Figure 2-7. Frequency Demodulator Output

Waveform CURRENT DEMODULATOR TEST

A. Check the following pa rameters at the given location:

PARAMETER LOCATION

IREAL Auxiliary Board Pin 5 IREACTIVE Auxiliary Board Pin 6

A. Since there is no current flow, the measured voltages will be:

Zero (0) Volts. Zero (0) Volts

VOLTAGE REGULATOR TEST

A. At run speed, rotate the VOLTS ADJUST control knob to its center position.

B. Monitor Test Point 12.

C. Monitor the VOLTAGE REFERENCE signal at AC Control Module Pin 551.


B. The voltage should be ≈-92 VDC @ 600 VAC.

C. The voltage should be ≈+4 to 6 VDC.



Table 2-3. AC Control Module Functional Test (Concluded) ACTION RESULTS

VOLTAGE REGULATOR TEST (CONCLUDED)

D. Monitor the EXCITER FIELD SUPPLY FIRING PULSE at AC Control Module Pin 504 (GATE A+).

D. The EXCITER FIELD SUPPLY FIRING

PULSE waveform should look like the one in Figure 2-8.

Figure 2-8. Exciter Field Supply Firing

Pulse Waveform FREQUENCY REGULATOR TEST

A. Rotate the SPEED ADJUST control knob t o its center position.

B. Monitor the SPEED REFERENCE signal at AC Control Module Pin 547.

C. Monitor the engine/generator's speed.


B. The voltage should be +4.0 to +6.0 VDC.

C. It must fall within the normal operating speed range of the engine/generator.



Table 2-4. Protection Circuit Functional Test

ACTION RESULTS

NO PULSE TRIP

A. Connect an engine/generator set to the Main AC Bus.

B. Disconnect TACH S IGNAL lead at AC Control Module Pin 526.

C. Test all remaining engine/generator sets by repeating Steps A and B.

This test applies only to systems equipped with a Tachometer Pulse Pickup circuit.

A. The Generator ON LINE light will illuminate.

B. The Generator Circuit Breaker will trip off line, the engine will die, and the Generator ON LINE light will extinguish.

C. Results will be as shown in Steps A and B.

REVERSE POWER TRIP

A. Connect a generator to the Main AC Bus.

B. Connect a jumper between AC Contr ol Module Pins 533 and 545 (this is the Throttle Output).

Connecting this jumper between pins 533 and 545 will cause a reverse power condition.

C. Once the Generator Circuit Breaker trips off line, remove the jumper between Pins 533 and 545.


B. The Generator Circuit Breaker corresponding to the gener ator will trip off line in eight to 10 Seconds.

C. The engine will return to RUN speed and the Generator Circuit Breaker will be in the OFF position.



Table 2-5. Calibration Procedure for Woodward EG-3P and EG-10P Actuators

ACTION RESULTS SETUP A. Connect an Ammeter in series with one of

the throttle leads which are connected to the Actuator receptacle.


B. Set the Ammeter scale to 100 mA. B. There are no measurable results from this step.

C. Open the Generator Circuit Breaker. C. There are no measurable results from this step.

D. Start the engine, and bring it up to RUN. D. There are no measurable results from this step.

TERMINAL SHAFT ADJUSTMENT A. Disconnect the coupling from the actuator shaft (refer to Figure 2-9). Adjust the actuator so that it draws 30 to 60 mA. Monitor the Ammeter of all actuators, in RUN, Off-line, with engine warmed up.

For each 2.5 mA of change desired, rotate the coupling on the threaded rod connected to the actuator shaft ½ to 1 turn. Actuators and linkages must also be set to conform with the engine manufacturer's specifications. A compromise between the engine manufacturer's specifications and the 30 to 60 mA figure may be necessary. CATERPILLAR Series 3500 engines do not conform to the 2.5 mA change per ½ to 1 turn of the coupling of the threaded rod.

A. On actuators produced beginning in 1980 Ammeter readings on all units should be within 10 mA of each other. On older units, the Ammeter readings may have to be the same for good load sharing. If you have questions, call the Ross Hill Field Service Office.

Figure 2-9. Actuator Linkage

REASSEMBLY A. Stop the engine.

B. Disconnect the Ammeter and reconnect the throttle lead.


B. There are no measurable results from this step.

LOCKNUT

THREADEDROD

ACTUATOR

ACTUATOR SHAFT



Table 2-6. Calibration Procedure for Woodward EG-B 10P Actuators Used on EMD Engines

ACTION RESULTS

ACTUATOR CURRENT CHECK

A. Remove the top cover plate by unscrewing the four corner screws.

B. Connect an Ammeter, set to read 100 mA, in

series with one of the throttle leads which are connected to the terminal strip located in the Engine Control Cabinet which is adjacent to the engine.

C. Open the Generator Circuit Breaker. Start the

engine, and bring it up to RUN. Monitor the actuator current.

D. Compare the actuator currents of all units.

This calibration procedure is to ensure that all of the actuators will work together. In most cases, if the actuator currents of all the actuators are within 10mA between the highest and lowest reading, they will perform properly.

A. A 1/8" Allen Head adjustable Spring Seat will be visible in the middle of the actuator about 1" (2.54 cM) below the top. The seat is held tight by a 5/16" lock nut.

B. There are no measurable results from this step. C. Record the actuator current, then repeat Steps

A, B, and C for all the actuators. D. Determine which (if any) of the actuators require

adjustment. If any do require adjustment, perform the following Terminal Shaft Adjustment procedure on the identified unit(s).

TERMINAL SHAFT ADJUSTMENT A. Loosen the Spring Se at lock nut. Rotate th e

Spring Seat 1/4 turn or less in either direction. B. Adjust the Spring Seat until the A mmeter reads

the same as other recorder actuator currents.

C. Tighten the Spring Seat lock nut.

PRESSING DOWN ON THE LOCK NUT CAN CAUSE THE ENGINE TO OVER SPEED.

A. Note that the actuator current changes.

B. All actuators should draw 30 to 60 mA when th e engines ar e at RUN RPM, Off -line, and at normal operating temperature.

C. There are no measurable results from this step.

REASSEMBLY A. Stop the engine.

B. Disconnect the ammeter from the actuator circuit and reconnect the throttle lead.

C. Reattach the top cover plate with the four screws.

A. There are no measurable results from this step.

B. There are no measurable results from this step. C. There are no measurable results from this step.



2.3 Theor y of Operation The Generator Unit controls the engine/generator set to deliver a constant AC supply to the Main AC Bus (refer to Figures 2-10 and Figure 2-11). Note that the AC Control Module contains the electronic Engine Governor, Voltage Regulator, Protection and Master/Slave circuits.

2.3.1 Hands-Off Circuit (HOC) The HOC consists of a battery charging circuit connected to two 12 Volt batteries. Phases A and B of the Main AC Bus are tapped, fused, and then rectified in a diode bridge to obtain the battery charging current. The batteries supply power for the Engine Starting circuit and the Pulse Pickup circuit in the AC Control Module (refer to Figures 2-11 and 2-12).

2.3.2 Generator Circuit Breaker The Generator Circuit Breaker isolates the Main AC Bus from the generator. It has a magnetic trip unit which trips the circuit breaker if current exceeds a preset value. The circuit breaker has a UV (Under Voltage) coil which is interlocked with an AC Control Module Protection circuit. This circuit trips the circuit breaker for various abnormal conditions such as reverse power, under/over-frequency and over-voltage.

2.3.3 Sy nchronization Panel When the Main AC Bus is energized and another generator supply is to be connected to the Main AC Bus, it is essential to match their voltage and frequencies before closing the Generator Circuit Breaker. This is accomplished by comparing the two frequencies by means of the Synchronization Box (shown in Figure 2-11). When the front panel SYNC switch is in the OFF position, the Sync panel VOLT meter indicates the Main AC Bus voltage. The needle of the SYNCHROSCOPE and the SYNC LIGHTS compare the frequencies of the Main AC Bus and the on-coming generator. The needle of the SYNCHROSCOPE rotates and the SYNC LIGHTS illuminate brightly when the two frequencies are out of phase. When the frequencies and phases are identical, there is no potential across the scope and the lights. As a result, the SYNCHROSCOPE needle remains stationary in the vertical position and both SYNC LIGHTS extinguish.



2.3.4 Engine Governor The electronic Engine Governor controls the engine speed and horsepower, and thereby regulate the generator frequency (refer to Figures 2-13 and 2-14). Located in the AC Control Module, the Engine Governor is a feedback control circuit. See the Unique Devices section of this manual for a general description of the feedback control circuit. The governor output is connected to a Throttle Control Actuator (this controls the engine fuel line valve). The Throttle Control Actuator opens the valve in direct proportion to the current applied by the governor through its coil. The coil signal can be monitored at the AC Control Module across Pin 533 (Throttle+) and Pin 545 (Throttle-).



ENGINE GOVERNOR (Continued)

Figure 2-10. Generator Unit Block Diagram



Figure 2-11. Generator Unit Circuit



Figure 2-11. Generator Unit Circuit (Continued)



Figure 2-11. Generator Unit Circuit (Concluded)



Figure 2-12. Hands-Off Circuit (HOC)



Figure 2-13. Engine Governor Block Diagram

RAMP CKT.

M/SSWITCH

THROTTLE

ENGINE

PULSEPICKUP

SPEED REFERENCE

ENGINE CONTROLSWITCH

MS LOGICMASTER/SLAVE

LOGICSLAVE

SLAVE

MASTERSLAVE

Z8 Z9 Q4

GEN.

GEN. BUSDEMODULATOR

Ι REAL FEEDBACK

SPEED FEEDBACK

THROTTLE LIMIT

AC MODULE

MASTER SLAVETO OTHER

GEN. UNITS

CURRENT CONTROL LOOP

SPEED CONTROL LOOP



Figure 2-14. AC Module Circuit



Figure 2-14. AC Module Circuit (Continued)



Figure 2-14. AC Module Circuit (Concluded)



The engine governor employs two feedback control loops. The Outer Speed Control Loop matches the actual generator frequency to the applied speed command. The Inner Current Control Loop matches the horsepower (KW) output of all engines on line. Speed Control Loop Op Amp Z8 issues a speed command which is proportional to the difference between the Speed Command and the Composite Speed Feedback. Speed Command is the Speed Reference signal as modified by the Engine Control switch ramp circuit and the Master/Slave Logic signal. Composite Speed Feedback is the sum of the Speed Feedback and Throttle Limit signals. Speed Reference This signal is set by the operator on the front panel SPEED ADJUST knob. The SPEED ADJUST knob is linked to a potentiometer which outputs a Zero to +11 VDC signal (pin 551). This corresponds to ≈46 to 54 Hz generator frequency. Engine Control Switch When the ENGINE CONTROL switch is moved from IDLE to RUN, the ramp circuit generates an ascending ramp. This steadily increases the gain of Op Amp Z8. The ramp circuit generates a descending ramp when the switch is moved from RUN to IDLE. Changeovers in engine speed are thus accomplished smoothly over a 10 Second time span. Master/Slave Logic A signal from the Master/Slave Logic circuit disables the Speed Reference signal when the Generator Unit is in the Slave mode. Speed Feedback This signal is a low-level DC analog of the engine speed. At TP 19 in the AC Control Module, the Speed Feedback signal is -2.5 VDC at 50 Hz and ≈+5.0 VDC at 35 to 40 Hz (the IDLE frequency). The Speed Feedback signal is derived either through a Tachometer Pulse Pickup circuit or a Voltage Demodulator circuit.



Pulse Pickup Circuit A magnetic pickup device is mounted near the flywheel of the engine. The magnetic Pickup device emits a pulse each time a flywheel tooth passes by. These pulses are applied to the Pulse Pickup circuit in the AC Control Module as Tach+ (pin 526) and Tach- (pin 527). The pulse signal is processed to derive the Speed Feedback signal. The magnetic pickup device generates it's own voltage and must produce ±2 VRMS. The Pulse Pickup also activates the HOC circuit (refer to Figure 2-12). This allows the HOC batteries to power the AC Control Module during the time that the generator voltage is building up. Frequency Demodulator Circuit Generator phase voltages out of AC Regulator transformer T10 are processed through a Demodulator circuit in the AC Control Module. The Demodulator output is inverted via Op Amp Z5 to obtain a negative Speed Feedback signal. Speed Feedback Switch The AC Control module is equipped with a circuit that permits the tachometer circuit to provide a speed feedback signal until the generator voltage is >200 VAC. When this occurs, the Speed Feedback Switch operates to connect the Frequency Demodulator Circuit output to the Frequency Regulator as the speed feedback signal. Speed Control Loop Op Amp Z9 issues a Throttle Current Command which is proportional to the error in signal levels between the Speed Command from Op Amp Z8 and the IREAL (KW) feedback. The output of Op Amp Z9 output is amplified through transistor Q4 and then applied to the Throttle Actuator Coil via Throttle+ (Pin 533) and Throttle- (Pin 545).

Master/Slave Logic The Master/Slave circuit decides which current command Z9 should receive. If the generator is a Master, the Generator Cubicle M/S switch selects the Z8 output. If, however, the generator is a Slave, the Generator Cubicle M/S switch selects the Master/Slave signal (pin 543). This signal is the Master generator Z8 output. The Master/Slave Logic circuit detects whether the generator is the Master or Slave. The Master/Slave Logic circuit receives the M/S Logic signal from the Generator Circuit Breaker (pin 544) and Slave signals which are the M/S Logic signals of the other generators (pins 537 through 542). Table 2-7 is the Master/Slave Truth Table.



Figure 2-15 shows the Master/Slave circuit. The Master/Slave Logic switches from ≈10 VDC (this voltage is approximate since it is partially dropped through a resistor) to -16 VDC when the circuit breaker is closed to connect the generator to the Main AC Bus. The Master/Slave Logic of each generator is connected to the Slave inputs of the following higher-numbered generators. As a result, the Master generator is always the one with the lowest number. Generator 1 is never a Slave unit since it doesn't receive any Slave inputs. If Generator 1 is off, the lowest-numbered generator connected to the Main AC Bus becomes the master. Note that Master/Slave lines of all generators are tied together.

Table 2-7. Master/Slave Truth Table

M/S Logic Slave Result

≈10 VDC ≈10 VDC The ge nerator is disconnected from the Main AC Bus.

-16 VDC ≈10 VDC The generator is the Master.

-16 VDC -16 VDC The generator is the Slave.

IREAL Feedback

IREAL is a low-level DC analog of the real current produced by the generator (IREAL x E = KW). Generator phase voltages out of transformer T10 and line currents out of CT1, CT2, and CT3 are processed in the AC Control Module through a current demodulator to develop ITOTAL, I REAL and IREACTIVE signals (refer to Figure 2-10).

2.3.5 Voltage Regulator This controls the generator's exciter current through the exciter power supply to regulate the generator voltage (refer to Figures 2-11, 2-13, 2-16, and 2-17). The Voltage Regulator output can be monitored across Generator EX+ (TB11-7) and Generator EX- (TB11-8). It should be +10 VDC during IDLE and ≤+70 VDC during RUN for a nominal 100 VDC exciter. The Voltage Regulator employs two Feedback Control Loops (Inner and Outer). The Outer provides overall regulation by matching the generator voltage to the Voltage Reference. The Inner regulates the Exciter Field Supply. Op Amp Z1 issues the Exciter Current Command. It is proportional to the error difference between the Voltage Reference and Voltage Feedback signals.



Figure 2-15. Master/Slave Wiring Diagram Voltage Reference This is set by the operator on the front panel VOLTS ADJUST knob. The knob is linked to a potentiometer which outputs a Zero to +11 VDC signal (Pin 551). This +11 VDC corresponds to maximum voltage. Voltage Feedback Voltage Feedback is a low-level DC analog of the generator voltage. The generator AC line voltages are applied to the primary of Control Transformer (600:115 VAC) T10. T10 has a Delta/Star configuration. The six AC phase voltages from the secondary are rectified and reduced in value to give the feedback signal. IREACTIVE is a low-level DC analog of the generator reactive current (IREACTIVE x E = KVARs).

Figure 2-16. Voltage Regulator Block Diagram

MS LOGIC

MASTER SLAVE

SLAVE

SLAVE

SLAVE

PIN NO. PIN NO. PIN NO.

AC MODULEGEN. 1

AC MODULEGEN. 2

AC MODULEGEN. 3

CB AUX. CB AUX. CB AUX.

-16 VDC -16 VDC -16 VDC

544 544 544

543 543 543

542 542 542

541 541 541

540 540 540

SCRFIRING

CIRCUITZ1 Z2

ACMTR

EXCITER

GEN.

BUS

GENERATOREXCITERFIELD

SUPPLY

VOLT.

REFER.

UNDER FREQUENCYCUTBACK

Ι

AC MODULE

VOLTAGE FEEDBACK

EXCITER CURRENT FEEDBACK

EXCITER CURRENT CONTROL LOOP

VOLTAGE CONTROL LOOP

REACTIVE



Figure 2-17. Exciter Field Supply Circuit The voltage feedback and current feedback signals are processed in the AC Control Module to derive the IREACTIVE signal. The IREACTIVE signal is negligible during startup when the circuit breaker is open since minimal current flows out of the generator. Voltage Reference is the only effective signal. The VOLTS ADJUST knob can be adjusted to set the generator voltage to the operating level. When several generators are connected to the Main AC Bus, the terminal voltage is held fixed by other generators. The VOLTS ADJUST knob can now be adjusted to bias the IREACTIVE signal so as to distribute the reactive current (KVARs) equally among all generators. The Underfrequency Cutback Signal is developed from the frequency feedback. It applies a negative bias to the summing junction of voltage regulator Op Amp Z1 to cutback the generator voltage when frequency drops below 42 Hz. At IDLE, when the frequency is approximately 30 to 38 Hz, the voltage is between ≈300 VAC to 450 VAC.

2.3.6 Exciter Current Control Loop Op Amp Z2 controls the SCR firing circuit firing angle so that the exciter field current matches the Op Amp Z1 current command. The generator output (refer to Figure 2-17) is stepped down and rectified to produce the exciter current. Two rectifier circuits are used: a diode bridge made up of DB1 and DB2 during startup. Thereafter, a half- controlled bridge made up of two diodes (DB2) and two SCRs (SCR1, SCR2). During startup, generator residual voltage is rectified through the diode bridge and applied to the Exciter. The Metal Oxide Varistor (MOV) clamps bridge voltage to +250 VDC. Through positive feedback, the Exciter voltage, and in turn, the generator voltage quickly builds up. When the voltage is sufficient to energize the AC



Control Module, build-up relay K1 energizes to switch the transformer output to the half-controlled bridge. The Exciter current feedback to the Op Amp Z2 summing junction (IEX + and IEX -) is +0.33 VDC per 1.0 Amp of Exciter current (or as adjusted by the connection of current-sensing resistors).

2.3.7 Protection Circuit This circuit (refer to Figures 2-13 and 2-18) compares the generator supply parameters against their respective preset limits. It consists of a Protection switch controlled by the reverse power, under/over-frequency and the over-voltage detector. The Protection switch, made up of transistor Q3 and relay K2, de-energizes the Under Voltage (UV) coil to trip the Generator Circuit Breaker. In some systems, the Generator Circuit Breaker has a Shunt Trip coil and a UV coil. In these systems, the Shunt Trip coil is wired to a switch on the Generator Cubicle. Closing this switch will energize the Shunt Trip coil, thus causing the Generator circuit breaker to trip.

Figure 2-18. Protection Circuit Block Diagram

GEN. BUS

AC MODULE

AC BUSAC

CIRCUITBREAKER

CBTRIP

NO PULSE

I REAL

FREQUENCYFEEDBACK

VOLTAGEFEEDBACK

REVERSEPOWER LIGHT

UNDER FREQ.CUTBACK

REVERSEPOWER

DETECTORZ6, Q1, K1

UNDER/OVERFREQUENCYDETECTOR

Z7, Z14

OVER VOLTAGEDETECTOR

Q6

PROTECTIONSWITCHQ3, K2 UV



2.3.8 Reverse Power Detector When an engine is running normally, it supplies power to the Main AC Bus. This power is measured in terms of KWs. The front panel KW METER will display a normal positive value (> zero). However, when fuel to the engine is cut off due to overtemperature, oil pressure or because of a clogged fuel filter, the corresponding KW meter will display a negative reading (below zero). This is because power flows from the bus into the generator of the faulty engine. The generator functions as a synchronous motor which keeps the faulty engine running. This is termed the reverse power phenomenon. Normally-running engines will force a faulty-running engine to run at the same speed because of the magnetic coupling linking the generators by way of the Main AC Bus. Comparator Z7 in the Protection circuit monitors the IREAL (Kilowatts) feedback signal to trigger the Protection switch when the signal exceeds the preset limit. The time delay before tripping of the circuit breaker is a function of the level of the reverse KW. For example, if reverse power is 7%, the Circuit Breaker will trip in eight to 12 Seconds.

2.3.9 Under-Fre quency Detector Comparator Z6 triggers the Protection switch if the frequency feedback signal indicates that the frequency is below 42 Hz. Z6 also applies the Underfrequency Cutback signal to the Voltage Regulator circuit to reduce generator voltage.

2.3.10 Over-Frequency Detector Comparator Z14 triggers the Protection switch if frequency feedback signal says that the frequency is 56 to 57 Hz.

2.3.11 Over-Voltage Detector The Voltage Feedback signal is applied to a voltage divider circuit made of resistors R90 and R96. The output of the voltage divider will trigger Q6 if the line voltage >≈1.16 x normal bus voltage.

2.3.12 No Pulse Detector The No Pulse signal will switch from +16 VDC to -16 VDC when the Pulse Pickup circuit does not receive pulses from the Magnetic Pickup device (this is located near the engine flywheel).



The Protection switch operates 100 mS after loss of magnetic pulses from the engine. This will prevent nuisance tripping of the circuit breaker.

2.4 Power Limit Circuit The Power Limit Circuit prevents the load from exceeding the capacity of engines on line. The circuit monitors IREAL (KWs) and ITOTAL (KVAs) of all the generators to keep the SCR bridges on line from demanding more of either KWs or KVAs that would exceed preset limits. This action distributes the available power equally among the SCR bridges. The power limit is normally set at ≈95% of the engine's horsepower rating and 100% of the generator's KVA rating. Note that IREAL and ITOTAL signals are generated in the AC Control Module and auctioneered together so that only the signal from the most highly loaded engine/ generator goes to the power limit circuit (see Figures 2-11, 2-14, 2-19 and 2-20)



Figure 2-19. Power Limit PC Card Schematic Diagram



Figure 2-20. Power Limit PC Card Layout



The IREAL and ITOTAL signals are low-level DC analog signals representing the real and total currents developed by the generator. Generator line currents are stepped down through current transformers CT1, CT2 and CT3. The resulting low level AC signals are rectified and processed in a current demodulator in the AC Control Module with the generator phase voltages and rectified to derive IREAL and ITOTAL. The IREAL and ITOTAL signals of all generators connected to the Main AC Bus are auctioneered to select the signals with the highest positive values. The Power Limit signal (Op Amp Z1-6) goes positive as the load increases. It is +0.25 to +0.5 VDC measured at Pin 12 of the Power Limit Board at power limit. When the load exceeds the power limit, the Power Limit signal positively biases the negative Firing Reference signals to all SCR bridges on line. Op Amp Z2 ramps input signal to Z1 from 75% of Power Limit to allow the prime mover to handle a large change demand for power. Transistor Q1 turns on at power limit to turn on the Driller's Console POWER LIMIT light. In some systems, Op Amp Z4 output is used to drive the Driller's Console POWER LIMIT meter.

2.5 AC Ground Fault Detection Circuit This circuit (refer to Figure 2-11) consists of three lights. One side of each light connects to a phase of the Main AC Bus. The light's other side is grounded. If an AC phase becomes grounded, the light corresponding to that phase is extinguished. The other two lights become more brightly illuminated. A small C.T. drives a meter to indicate the percent of the AC ground. This manual's SCR Unit section describes the DC Ground Fault Detection circuit.

2.6 TROUBLESHOOTING Table 2-8 gives troubleshooting information for engine malfunctions. Table 2-9 gives troubleshooting information for Generator malfunctions. Table 2-10 gives troubleshooting information for the AC Control Module.



Table 2-8. Engine Malfunctions SYMPTOM/PROBABLE CAUSE ACTION

ENGINE WILL NOT RUN

A. Engine overspeed lever not reset. A. Reset the lever. B. No power to the a ctuator. Throttle drops shut if

the fuel rack is n ot held open by ha nd. Th e possible causes are:

B. The actions for the possible causes are:

1. Leads to the throttle actuator are either open, short-circuited, or grounded.

1. Measure resistance between Generator TB11-1 and Generator TB11-2 (Throttle + and -) with both leads lifted. It should read 30Ω.

2. The AC Co ntrol Modul e in the Generato r Cubicle is no t providing control current to the throttle.

2. Measure current going to the Throttle Actuato r at throttle + or Throttle -. It s hould be 30 to 60 mA when e ngine is at run speed. If there is n o or low current, replace the AC Control Module.

3. No signal from the e ngine pul se pickup (if used).

3. Set the Voltmeter on it's lowest AC Volts range. The pulse pickup must deliver at least 2 VAC at engine crank speeds.

ENGINE RUNNING PROBLEMS

A. Engine speed oscillates up and down at a steady rate. Observe the engine throttle arm.

A. Speed may oscillate for a sho rt time durin g col d starts (this is normal). If it continues to oscillate, the AC Cont rol Module may be malfuncti oning. If so, call Ross Hill.

B. Engine speed vari es erratically wit hout any steady oscillation. The possible causes are:

B. The actions for the possible causes are:

1. Intermittent connection on the throttle circuit. 1. Check for/repair any intermittent connections. 2. Defective AC Control Module. 2. Replace with spare AC Control Module.

C. Engine speed cannot be raised to 50 Hz. C. The A C control voltage s from tran sformers n ot reaching the AC Control Module. Troubleshoot and repair. With the EG-B-1 0P throttle actuator, be sure SPEED knob setting is set to MAXIMUM.

D. Engine speed cannot be adjusted.

D. Faulty SPEED ADJUST rheostat. Troubleshoot and

repair. E. Engine speed and KW sharing problems. E. AC Control Module is defective. Check the actuator

current. F. Generator Circuit Breaker does not a utomatically

trip for reverse power, under/overfrequency, or no pulse faults. There are two possible causes:

F. The actions for the possible causes are:

1. Defective AC Control Module. 1. Replace with spare. 2. Circuit Breaker UV is faulty. 2. Troubleshoot and repair/replace as required.



Table 2-9. Generator Malfunctions SYMPTOM/PROBABLE CAUSE ACTION

AC VOLTS ABSENT OR <150 VAC. A. Engine speed is too low. A. If the Main AC Bus voltage will not increa s e,

raise the speed to RUN setting when starting. Measure the voltage across Exciter Field+ (GEN TB11-7) an d Exciter Field- (GE N TB11-8 ). It must be at le ast 1 VAC d uring starting. Check the Generator Residual Voltage. At full speed, it should be ≈15 to 20 VAC. If both of the above conditions do not exist, the Generator Residual Voltage is insufficient. In this case, supply an external current to the Generator Exciter Field (this proced ure i s call ed flashing the Exciter Field ).

B. Exciter fuses are blown, or the Exciter Fiel d Supply Circuit is defective.

B. Troubleshoot the Exciter Field Supply Circuit.

C. Shorted diode in the generator rotating rectifier. C. Troubleshoot and repair the generator. D. Generator Residual Voltage insufficient. D. Flash the Exciter Field. AC VO LTAGE REACHES 150 TO 200 VAC BUT DOES NOT INCREASE TO 600 VAC

A. Defective Exciter Printed Circuit Card. A. Replace the Exciter Printed Circuit Card. B. Defective AC Control Module. B. Replace with spare AC Control Module.



Table 2-10. AC Module Troubleshooting

SYMPTOM/PROBABLE CAUSE ACTION POWER SUPPLY TRANSFORMER A. The Generator Voltage is high. A. Check the voltage s on P ins 51 2 thro ugh 51 7 are missi ng

(they sh ould each be 11 5 VAC mea sured i n refe rence to ground). Absence of any will cause this condition.

Check the S afety Fuses and Fuses F33, F3 4, a nd F 35. Replace if re quired. If the problem repeats, replace the AC Control Module.

DC POWER SUPPLY A. The KVAR and KW meter nee dles

oscillate against their Zero Stop pin. A. Measure the voltage at t he follo wing AC Control Module

Pins: Pin Voltage

501 Zero Volts (This point is ground) 502 +16( ± 0.15) VDC 503 -16( ± 0.15) VDC 546 +11( ± 0.15) VDC

These voltages should be present whenever the Generator voltage >250 VAC. This condition can be caused by Pin 501 not being tie d to grou nd and TB4-1 0. Troubl eshoot and repair/replace as required.

B. Generator Voltage rea ches 6 00 VAC but DC Power Supply is not working correctly.

B. Measure the voltage at the following AC Control Module Pins when the Generator Voltage is 600 VAC:

Pin Voltage 502 +16( ± 0.15) VDC 503 -16( ± 0.15) VDC 507 -160( ± 20) VDC 508 +160( ± 20) VDC

If voltages are incorre ct or missin g, troubl eshoot an d repair/replace as required.

GENERATOR VOLTAGE REFERENCE A. Unable to adjust generator voltage. A. A low re ading at Pin 55 1 of the AC Control M odule will

cause this p roblem. Ensure that the VOLTS ADJUST is set at ≈ half rotation. Measure the voltage at Pin 551, i t should read ≈+6 VDC when the Generator Output is 600 VAC. The range a djustment for the Gen erator Voltage Reference i s Zero to +11 VDC. If the voltage at Pin 551 is missing, trouble shoot and repair/replace as required.

ENGINE SPEED REFERENCE A. Engine speed is low a nd/or AC Ci rcuit

Breaker trips due to underfrequency. A. Absence of a signal at Pin 547 of the AC Control Module will

cause this problem. Set the SPEED REFERENCE to 50 Hz and then me asure the vol tage at Pin 547. It should be +6 VDC. The range adjustment for the Engine Speed Reference



SYMPTOM/PROBABLE CAUSE ACTION is Zero to +11 VDC.

If the voltage at Pin 54 7 is mi ssing, trouble shoot and repair/replace as required.

CIRCUIT BREAKER TRIP A. Circuit Breaker has tripped. A. Measure the voltage betwee n Pins 5 28 and 5 29 (the UV

Trip). The voltage should be Zero Volts. If the voltage is +24 VDC, The T rip Relay in the AC Cont rol M odule h as not picked up and the Circuit Breaker has tripped.

THROTTLE OUTPUT A. Engine will only run when throttle is

held by hand. A. Measure the current from either Pin 533 or 545 when the

engine is at RUN speed with NO LOAD, the reading should be 30 to 60 mA. If the engine is at RUN speed with FULL LOAD, the reading should be 180 to 200 mA. Check for an ope n ci rcuit betwee n the throttle le ads and repair/replace as requi red. If the actuator resistance is 30 to 36Ω try replacing the AC Control Module.

EXCITER SCR GATE PULSES A. The Generator Voltage oscillates

between 10 VAC and 300 VAC as the Field Supply Build-Up Relay opens and closes.

A. Using an O scilloscope, che ck for the pre sence of firing pulses at AC Control Module Pins 504 and 505. If the firing pulses a re missing, repl ace the AC Contro l Module.

EXCITER CURRENT FEEDBACK A. Generator voltages out of regulation. A. Use an Oscilloscope to monitor the voltage between Pin 556

of the AC Control Mod ule and g round. Com pare this waveform with the waveform of a known good generator.

AC CURRENT FEEDBACK A. There is a lo ad imbalance between the

generators conne cted to the Main AC Bus.

A. Measure the voltage bet ween the fo llowing AC Control Module Pins with an Oscil loscope: 519 to 520, 521 to 522, and 523 to 524. The voltage measured should be Zero Volts at NO LOAD, and +2.5 VDC at FULL LOAD . If the voltage between a ny of these A C Control Mo dule Pins i s missing, troubleshoot and repair/replace as required.

MASTER/SLAVE A. A large KW load imbala nce bet ween

the en gines. This is pro bably caused by impro per a ctuator current adjustment.

There are several other, though less comm on, reas ons for a large KW load imbala nce: a defective KW Meter, a defective AC Co ntrol Module, a bad Actuator, or an engine problem.

A. Start an eng ine/generator and allow it to operate un til it is at normal running temperatu re. Adjust the generator fr equency to 50 Hz. Disconnect the generater circuit breaker a nd then measure the actuator current at e ither Pin 533 or 5 45 of the AC Control b y connecting a multime ter (set on the 1 00 mA scale) in series with the wire going to the pin. Actuator current must be 30 to 60 mA. If it is not within that range, adjust until it is. Perform this with all o f the engine/generators. Ensure that all of them have an ac tuator current tha t falls within a 10 mA range betwe en the smallest and lar gest. All actuator's currents must fall with the 30 to 60mA range given above.



3 HI-LINE OPERATION Hi-Line operation allows you to replace or supplement the electrical power obtained from your engine/generators with electrical power obtained from a commercial power company. If this source of power is available at your site, the cost savings of utilizing Hi-Line operation can be considerable. The Hi-Line operation is primarily performed by a step-down transformer and two circuit breakers (refer to Figure 2-21). There are other circuit components that allow control or monitoring of Hi-Line operation. These other components are shown in Figure 2-22.

Figure 2-21. Typical Basic Hi-Line The values for the step-down transformer and circuit breakers shown in Figure 2-21 are given for illustration purposes. The values selected for your particular system may differ. In Figure 2-21, either or both of the circuit breakers will supply voltage from the step-down transformer to the system's AC Bus. If only one circuit breaker is closed, the power delivered to the system's AC Bus will be limited to the rating of the connected circuit breaker (typically ≈50% of the step-down transformer's rating). Figure 2-22 shows the lineup of a typical SCR system containing a Hi-Line Incomer Cubicle. The two circuit breakers in Figure 2-21 labelled MCB1 and MCB2 are the same as the Items 31(Hi-Line Incomer Circuit Breaker) in Figure 2-22. In the following item descriptions, all references are to items shown in Figure 2-22. Three items are Hi-Line controls: • REVERSE POWER TRIP RESET Lighted Push Button (LPB) switch (Item 40).

• Two HI-LINE INCOMER CIRCUIT BREAKERs (Items 31).

BUS

600 VAC

13,800 V (or Higher)3000 KVA

MCB11600AF

MCB21600AF/AT

LOCATED INHI-LINE CUBICLE



The REVERSE POWER TRIP LPB is disabled if the Engine/Generator cannot be paralleled with the Hi-Line Transformer. The remainder of the items on the Hi-Line Incomer Cubicle are indicator lights or meters. The AC AMMETER (Item 32) displays the total current being supplied by the Hi-Line's step-down transformer. The KILOWATT METER (Item 33) displays the total real power being supplied by the Hi-Line Incomer Cubicle. The KVAR METER (Item 34) displays the total reactive power being supplied by the Hi-Line Incomer Cubicle. The AC VOLTMETER displays the AC voltage being supplied by the Hi-Line Incomer Cubicle to the Main AC Bus. The UTILITY OK (Item 35) lamp illuminates if there is no problem with the incoming commercial power. The REVERSE PHASE ROTATION lamp (Item 36) illuminates if the incoming commercial power has been connected out of phase with the Main AC Bus. The PHASE LOSS lamp (Item 37) illuminates if there is a phase loss of the incoming commercial power. The MCB1 CLOSED lamp (Item 41) illuminates if Main Circuit Breaker 1 is closed. The MCB2 CLOSED lamp (Item 42) illuminates if Main Circuit Breaker 2 is closed.



Figure 2-22. Typical SCR System Containing a Hi-Line Incomer Cubicle



4 REMOVAL & REPAIR

4.1 Model 1000 In the Model 1000, the Generator Unit assemblies (refer to Figure 2-23) are mounted inside the Generator Cubicle on the door and side panels.

Figure 2-23. Model 1000 SCR/Generator Cubicle




Figure 2-24. Model 1400 Generator Cubicle




Figure 2-25. Model 1861 Generator Cubicle



THIS PAGE INTENTIONALLY BLANK


www.nov.com

Section 1.3 SCR Unit

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 68


DISCIPLINE


REFERENCE



National-Oilwell Varco 11000 Corporate Centre Dr Houston, Texas 77041 USA Phone +1 281 854 0400 Fax +1 281 854 0607

DOCUMENT NUMBER

D257272-1200-MAN-003 REV

01

Technical Manual

50 Hz SCR Unit

Note



www.nov.com

Section 1.4 Drillers Console

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 41


DISCIPLINE


REFERENCE




DOCUMENT NUMBER

D257272-1200-MAN-004 REV

01

Technical Manual

Driller’s Console

Note



www.nov.com

Section 1.5 Transformer Feeder Unit

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 5


DISCIPLINE


REFERENCE




DOCUMENT NUMBER

D257272-1200-MAN-005 REV

01

Technical Manual

Transformer Feeder Unit

Note



www.nov.com

Section 1.6 Motor Control Center

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 12


DISCIPLINE


REFERENCE




DOCUMENT NUMBER

D257272-1200-MAN-006 REV

01

Technical Manual

50 Hz Motor Control Center

Note



www.nov.com

Section 1.7 Drawworks Braking

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 28


DISCIPLINE


REFERENCE



National Oilwell Varco 11000 Corporate Centre Dr Houston, TX 77041 USA Phone +1 281-854-0400 Fax +1 281-854-0607

DOCUMENT NUMBER

D257272-1200-MAN-007 REV

01

Technical Manual

Drawworks Braking

Note



www.nov.com

Section 1.8 Unique Devices

www.nov.com

RIG/PLANT


SDRL CODE

TOTAL PGS 110


DISCIPLINE


REFERENCE



National-Oilwell Varco 11000 Corporate Centre Dr. Houston, Texas 77041 USA Phone +1 281 854 0400 Fax +1 281 854 0607

DOCUMENT NUMBER

D257272-1200-MAN-008 REV

01

Technical Manual

Unique Devices

Note



www.nov.com

Section 1.9 Spare Parts List

ADDITIONAL CODE SDRL CODE TOTAL PGS

4

DISCIPLINE

PhoneFax

DOCUMENT NUMBER REVISION

RIG/PLANT

Mobile Modular Work Over Unit-1stREFERENCE DESCRIPTIONREFERENCE

REMARKS

CLIENT PO NUMBER

MAIN TAG NUMBER

GMK710301D

01D257272-1200-SPL-001

www.nov.com

CLIENT DOCUMENT NUMBER

Spare Parts List

M1000 SCR/Generator Control

National Oilwell VarcoThis document contains proprietary and confidential information which belongs to National Oilwell Varco, it is loaned for limited purposes only and remains the property of National Oilwell Varco. Reproduction, in whole or in part, or use of this design or distribution of this information to others is not permitted without the express written consent of National Oilwell. This document isto be returned to National Oilwell Varco upon request and in any event upon completion of the use for which it was loaned.© Copyright National Oilwell Varco

7272 C00,01,02,04 Engineering & Marine Services (PTE) LTD.

281 854 0400281 854 0607

Rig Solutions - Western Hemisphere11000 Corporate Centre DrHouston Texas 77041

Page: 2

D257272-1200-SPL-00101

REVISION HISTORY

01 18.12.2008 Issued for Information SMA NEG KMRev. Date (dd.mm.yyyy) Reason for issue Prep. Check Appr.

Document Number:Revision:

www.nov.com

Page: 3

Item

No.

Description of Recommended Spare Parts Item / Ref. No. NOI Part No.

Rec

omm

ende

d

Qua

ntity

to b

e or

dere

d

Rec

omm

ende

d

Qua

ntity

to b

e or

dere

d

Uni

t Pric

e (_

_)

US

D (C

urre

ncy)

Del

iver

y tim

e fo

r par

ts (i

n w

eeks

)

1 ALARM-120VAC,HORN,GREY FEDERAL 0408-0001-00 12 BDGE- 30A,1000V,1PH 0000-6817-69 23 BLWR-E/1 ,600V,1PH,.75HP,60HZ 0100-0302-01 14 CAP- 1 MFD,2000VDC 0505-0014-00 15 CB-1200 ,3P, 600VAC, 42KIC,1 200AF,NON AUTO � 0302-1636-03 16 CB-1600AF,3P, 600VAC, 65KIC W/ACC,SHF16B216- 0000-6975-23 17 CB-CLOSING COIL,120VAC,F/POWER BREAK II,REMOTE CLOSE 0000-6972-34 18 CB-CONT,0A0B2C,FUW SPECTRA RMS F/SGLA CB'S � 0000-6897-31 19 CB-UVR, 24VDC,F/GE POWER BREAK II � 0000-6982-13 110 CB-UVR, 24VDC,FUW ALL SPECTRA RMS CB'S � 0000-6927-67 111 CONN-OUTLET BOX,1.5X4X4,W/.5KO 1102-0063-00 112 CONN-RECP,3W,2P,15A 0002-0523-45 113 CONT-BLK,0A1B0C,OT,RED 0000-6854-48 214 CONT-BLK,1A0B0C,OT,GRN 0000-6854-47 215 CONTR-1250A, P,1000VDC,125VDC COIL, A B C CONT,A/C � 0401-0015-00 216 CONTR-1800A,1P, V C, 74VDC COIL,ROSS HILL,MDL 1800/C � 0100-0389-02 317 DIAL-15TURN REPL D211 BECKMAN � 0609-0002-00 118 FUSE- .6A, 500V C, 10KIC, CLASS M � 0301-0009-00 2019 FUSE- 2. A, 500V C, 10KIC, CLASS M � 0301-0010-00 2020 FUSE- 3.5A, 500V C, 10KIC, CLASS, � 0301-0011-00 2021 FUSE- 6. A, 500V C, 10KIC, CLASS M � 0301-0012-00 2022 FUSE- 15. A, 600VAC,200KIC CLASS CC � 0000-6981-43 2023 FUSE- 900. A, 1300V C, KIC, CLASS,IND 0000-6935-14 1024 FUSE-HOLDER,1P, 30A, 600VAC, CLASS M � 0000-6984-02 125 FUSE-HOLDER,2P, 30A, 600VAC, CLASS M � 0000-6988-00 126 FUSE-HOLDER,3P, 30A, 600VAC, CLASS M � 0000-6988-01 127 FUSE-HOLDER,3P,30A,600VAC,FUW 1.5" FUSE,UL 0000-6980-71 128 KNOB-S/S,ROTARY TORQUE LMT 0613-1233-01 129 METER-AAC,0-1500,HOYT,0-1MADC, 200 OHM,NOI LOGO � 0801-0009-22 130 METER-ADC,0-1000,EDGE,0-1MA RA TING,TYPE 185 0000-6810-01 131 METER-ADC,0-1500,HOYT,0-1MADC, 200 OHM,NOI LOGO � 0801-0070-22 132 METER-HOUR,99999.HRS,120V,60HZ NON RESET,2.5"SQ 0000-6905-90 133 METER-KW,0-1200,HOYT,0-1MADC, P250002-0007-62 134 METER-PWR LMT,0-100%,PANEL,EDG EWISE,HORIZONTAL,0- 0801-0071-00 135 METER-VDC,0-1000,HOYT,0-1MADC, 200 OHM,N.O.V. LOGO � 0801-0060-22 136 MODULE-AC,(JOB CAL'D) 0521-2500-00 137 MODULE-DC,SERIES,W/1K OHM RES INSTALLED FOR VFB AT � 0522-2400-27 138 PB-110VAC ,30MM,YEL,MOMENT P250000-9692-93 139 PB-CAP,RED,DUST CVR 0000-6921-48 140 PB-CONT,1A0B0C, 6A,FUW MPX P250000-9692-97 141 PB-KIT, A B C,3HD OFF-IDLE-RUN 0100-1518-01 142 PB-RING,PROT F/MSHRM HD P/P 0000-6961-13 143 PCA-3PH (L-N) CUR FDBK W/1 OHM 10W BURDEN (X2) M1 � 0510-0400-00 144 PCA-VOLTAGE FEEDBACK 0509-3000-00 145 PC-DRLS CONS,ADD:JUMPER-PIN 1 TO D23 CATHODE � 0509-2500-01 146 PC-GEN EXC,REV 120 OR 240V RATED � 0509-7901-00 147 PC-S&A,PWR SPLY,60V 0510-0500-00 148 PL- 24VAC/DC,22MM,GRN LED,COMP 0406-0061-00 149 PL-110VAC ,22MM,CLR LED,COMP DC,22MM,RED INTEGRATED P250000-9692-38 150 PL-110VAC ,22MM,RED LED,COMP 0406-0065-00 151 PL-110VAC ,22MM,YEL LED,COMP 0406-0067-00 152 PL-110VAC ,30MM,RED LED,KIT (ML1-100R)+LAMP P250000-9692-31 153 PL-110VAC ,30MM,WHT LED,KIT (ML1-100W)+LAMP P250000-9692-35 154 REGULATOR-W/FILTER,0-15PSI W/G AUGE,20 MICRON 0000-6892-12 1

TWO YEAR OPER. SPARES

MATERIALS DATA COMMISSIONING SPARES

SPARE PARTS LIST

DOC. NO:D257272-1200-SPL-001INQUIRY NO:

EQUIPMENT DESCRIPTION

TAG No. P.O. No.

NOI Part No.

Currency

USD

Ref./Ser. No.

Engineering contractor: National Oilwell Suppliers name and address: National Oilwell, 1530 W. Sam Houston Pkwy.N, Houston TX 77043Phone Numbers : Phone: 713-935-8000, Fax.: 713-935-8305Suppliers contact person: After Sales Spare Parts: Clifton Hartoon (Extension # 7411)EMAIL: [email protected]

126-016632

Ref. BOM No.Rig

Ocean Endeavor

CustomerEngineering &

Marine Services

SPARE PARTS LIST

INQUIRY NO:

TAG No. P.O. No.

NOI Part No.

Currency

USD

Ref./Ser. No.

Engineering contractor: National Oilwell VarcoSuppliers name and address: National Oilwell Varco, 1530 W. Sam Houston Pkwy.N, Houston TX 77043Phone Numbers : Phone: 713-935-8000, Fax.: 713-935-8305Suppliers contact person: After Sales Spare Parts: GERRY.WHITE (Extension # 8898)EMAIL: [email protected]

GMK710301D

Ref. BOM No.RigVSP Platfrom Work

Over

Customer

M1000 SCR/Generator Control

www.nov.com

Page: 4SPARE PARTS LISTSPARE PARTS LIST

55 RES- 25. OHM, 55W, 5% 0504-0012-00 156 RES-150. OHM,225W, 5% (OLD CAT# 0905) � 0504-0005-00 157 RHEOSTAT- 1KOHM, 25W, %,TY PE H � 0506-0001-00 158 RHEOSTAT- 1KOHM,DUAL ASSY,RTI LMT � 0100-0135-00 159 RLY-120VAC,2A2B0C, 10A,IEC DE- VICE,50/60HZ � 0000-6808-51 260 RLY-120VAC,4A0B0C, 10A,IEC D EVICE,50/60HZ � 0000-6941-50 161 SCR-2000V,1200A,DV/DT=1KV/USECW/19" LEADS,150USEC TURN 0501-0616-10 662 SW 611G8005 PRESSURE PUFFER SWEIVEN DUAP SNAP SUB � I110-001008 163 SW- W-2,1-1-12,12P NONSHORTING ROLLER � 0000-6880-37 164 SW-MICRO,250V,10A RATED,U/W0000-6953-60. 0000-6953-61 265 SW-PB,1A,1B,2 POS,PUSH/PULL TY PE,RED CAP � 0000-6803-64 166 SW-PRESS,1.4 -5.5 IN WTR DIFF 0000-6837-15 167 SW-SEL,2POS,LEVER,OT OPR 0000-6854-44 168 SW-SEL,3POS,LEVER,OT OPR 0000-6854-45 169 SW-TEMP,190+/- 5DEG F OPEN ONRISE,160+/- 7DEG F CLOSE ON 0403-0008-01 270 XFMR- 2KVA,600 :240/120,CPT 1PH,60HZ,EXCITER � 1003-0091-01 171 XFMR- 50VA,600 : 26.5 ,CPT 1003-0095-00 172 XFMR- 66VA,600 :115/ 11,CPT DEL:DEL & 6PH WYE,DC 1003-0007-00 173 XFMR-140VA,600 :115 ,CPT DEL:6PH WYE,AC REGULATOR 1003-0008-00 174 XFMR-150VA,600 : 45 ,CPT DEL:3PH WYE,CONTR SPLY � 1003-0066-00 175 XFMR-PULSE,26. :14. T,W/BLACKEPOXY RESIN,DRILLING 0100-0357-00 1

www.nov.com


www.nov.com

Section 1.10 SCR/Gen Test Procedure

www.nov.com

Mobile Modular Workover Unit-1st

RIG/PLANT

ADDITIONAL CODE

SDRL CODE

TOTAL PGS

32 REMARKS

MAIN TAG NUMBER

DISCIPLINE

CLIENT PO NUMBER


REFERENCE

J257272 REFERENCE DESCRIPTION

Engineering & Marine Services (PTE) LTD. This document contains proprietary and confidential information which belongs to National Oilwell Varco; it is loaned for limited purposes only and remains the property of National Oilwell. Reproduction, in whole or in part; or use of this design or distribution of this information to others is not permitted without the express written consent of National Oilwell Varco. This document is to be returned to National Oilwell Varco upon request and in any event upon completion of the use for which it was loaned. © National Oilwell Varco

National Oilwell Varco Rig Solution Group 1530 W. Sam Houston Pky N Houston, Texas 77043 (USA) Phone + 713-935-8000 Fax + 713-827-8460

DOCUMENT NUMBER

D257272-1200-PRO-001 REV

02

SCR/Gen Test Procedure

SCR/Generator Line-up Test Procedure

Note



www.nov.com

Section 1.11 Certificate of Compliance

RIG/PLANT Mobile Modular Work Over Unit-1st

REFERENCE

7272 C00,02 REFERENCE DESCRIPTION

Engineering & Marine Services (PTE) LTD ADDITIONAL CODE

SDRL CODE

TOTAL PGS 4


DISCIP NE LI

CLIENT PO NUMBER GMK710301D

This document contains proprietary and confidential information which belongs to National Oilwell Varco, it is loaned for limited purposes only and remains the property of National Oilwell Varco. Reproduction, in whole or in part, or use of this design or distribution of this information to others is not permitted without the express written consent of National Oilwell. This document is to be returned to National Oilwell Varco upon request and in any event upon completion of the use for which it was loaned. © Copyright National Oilwell Varco - 2006

National Oilwell Varco Rig Solutions - Western Hemisphere 11000 Corporate Centre Dr Houston Texas 77041 Phone 281 854 0400 Fax 281 854 0607


DOCUMENT NUMBER

D257272-1200-CER-001 REV

01

Certificate of Compliance

VSP WORKOVER RIG SCR / GENERATOR CONTROL

www.nov.com

d257272-1200-fdd-002-r1.pdf

Documents

scrgenerator control

scr unit

generator unit

maintenance manual po

document number d257272

transformer feeder unit

mmwu page

motor control center