EDG Mechnaical

Question 1

Discuss EDG air compressors rating and tech spec value

Answer 1

Air start receivers are capable of 5 starts together or 2 solo.
Tech spec value 310#
Back-up compressor is only for Control air not starting air
Main Air compressor is deenergized by HR9 Relay of EPS

Question 2

Discuss EDG local remote switch on auto start signals

Answer 2

In REMOTE EDG will start as normal
In LOCAL only LOP will start Diesel, BKR will not auto close
In MAINTENACE EDG will not auto start

Question 3

Discuss EDG HSR

Answer 3

HSR: engine speed> 375 RPM or Coolant pressure >375 RPM equivalent

• DAH fans start
• Starting air cutout
• Back up Field flash (normal start only flash, E-start 2nd try)
• Jacket HTR and Keep warm pumps are off
• Arm alarm and shutdown Circuits after 7 second delay

Question 4

Discuss EDG LO-LO Speed Relay

Answer 4

LSR: 95 RPM

Air shut off, starting air is no longer admitted to EDG

Question 5

Discuss EDG LSR

Answer 5

LSR: 125 RPM

• Drops out start circuit relays
• Opens SW to DG HX
• Starts Crankcase Exhauster
• Flashes Field (e-start)
• De-energizes Generator space heater

Question 6

Tech Specs for Fuel oil and capacities

Answer 6

FOST: 75,000 capacity 62,000 TS Limit (60,000 modes 5/6)
FODT: 1,500 capacity 600 TS Limit

Question 7

Motor driven and aux lube oil pump auto start

Answer 7

HSR energized and 1 of 2
OPL1 (70#) or OPL2 (65#)
Stays running once started

Question 8

Motor driven Aux coolant pump auto start

Answer 8

HSR energized and

<25# Jacket or <24.5# Air Cooling loop

Question 9

List EDG Trips

Answer 9

Engine over Speed - 110 to 112%
2/3 low lube oil pressure OPL-2,3,4 (65#, 60#, 60#)
Generator Differential (86DP)
Emergency Stop
Hi Lube oil temp 173F (note 1 and 2)
Hi Jacket Coolant temp 195F (note 1 and 2)
Generator Backup Protection (86DB) (Note 1)
Note 1: Trips bypassed on SI via RLA relay
Note 2: Trips bypassed on E-start

Question 10

List MCB status light indication for EDG

Answer 10

EDG Not Available
EDG Parallel Operations
EDG Back up protection Bypassed (SI)
EDG Local Control
EDG Emergency start (LOP/SI/E-start)
EDG EDG Maintenance
EDG High Temp Bypassed (any E-start)
EDG Regulator in manual

Question 11

State when EDG governor swaps between isochronous and Droop

Answer 11

If EDG is paralleled then it will be in DROOP

Question 12

What happens when EDG gets a shutdown Signal

Answer 12

The Shutdown Solenoid is energized, this sends air to opposite side of the rack boost cylinder

Question 13

Motor Driven Fuel Oil pump start signal

Answer 13

15# at outlet of filter and speed>HSR

Stays running until EDG is shutdown

Question 14

Discuss EDG LO heatexchanger

Answer 14

3-way control valve Maintains temperature between 125F and 142F