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Diesel Generators Flashcards

1
Q

What are the Unit 1 DG Ratings?

A

Continuous: 3500 KW
2000 Hours: 3730 KW

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2
Q

What are the Unit 2 DG Ratings?

A

Continuous: 3685 KW
2000 Hours: 3935 KW

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3
Q

State the purpose of the Diesel Generator Electronic Governor.

A

Controls engine speed at 450 or 900 rpm.

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4
Q

What is the Diesel Generator Tech Spec Criteria?

A

900 rpm and output breaker closed w/in 10 sec
60 ± 1.2 Hz and 4160 ± 420 Volts.

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5
Q

What is the purpose of the Diesel Generator Mechanical Governor?

A

Backs up the Electrical governor.
Receives a BOOST signal from the air start system to help open the fuel racks when initially starting the EDG

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6
Q

Describe the Diesel Generator Governor operation in Normal Mode.

A

Operator control of parameters. Droop present during paralleled operation.

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7
Q

Describe Diesel Generator Governor operation in Emergency Mode.

A

Enabled when EDG Start Signal present AND 3-2 Tie Breaker is Open
* Speed can no longer be adjusted by the operator
* Voltage Regulator swaps to Unity (no voltage droop). However voltage can still be manually adjusted.

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8
Q

Describe Diesel Generator Governor operation in Transition Mode.

A

When SWYD power is regained after a LOOP, this mode allows the operator control of EDG speed to begin parallel ops and restore offsite power to our in-house buses.
* Occurs when Sync SS is placed in the “Tie-A3 (B3)” position
* When the 3-2 tie breaker has been re-closed, the EDG Governor shifts back to speed droop mode.
* When SIAS & LOOP have been reset, the Voltage Regulator shifts back to speed droop mode.

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9
Q

What happens when the EDG Governor fails while the EDG is running unloaded?

A

EDG increases to 940 rpm & 62.8 Hz

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10
Q

What happens when the EDG Governor fails while EDG is running loaded to the grid?

A

KW loading will go up to ~4000KW, increased fuel consumption.

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11
Q

What happens when the EDG Governor fails while EDG running loaded following a LOOP?

A

EDG increases to 940 rpm & 62.8 Hz

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12
Q

Describe the air flow path through the Unit 1 EDG.

A
  • Through steel louvers into EDG building
  • EDG Building air then enters the Air Intake box on top of Generators thru intake filters and flows into the Turbocharger, which compresses air to get more energy out of it.
  • After exiting the Turbocharger, the air passes through the After-cooler, which removes the heat added by the turbocharger before it enters the engine.
  • Air then enters a common air header which supplies air to each of the cylinders
  • After exiting the cylinders, engine exhaust air flows through the turbocharger turbine, providing the motive force for its operation
  • Exhaust air leaves via a Flexible Connection to Exhaust Bellows From the exhaust bellows, air travels thru exhaust ductwork exits the EDG buildings
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13
Q

Describe the air flow path through the Unit 2 EDG.

A
  • Through louvers & screens into EDG bldg.
  • EDG Building air then enters the Air Intake box on top of Generators thru intake filters and flows into the Turbocharger, which compresses air to get more energy out of it.
  • After exiting the Turbocharger, the air passes through the After-cooler, which removes the heat added by the turbocharger before it enters the engine.
  • Air then enters a common air header which supplies air to each of the cylinders
  • After exiting the cylinders, engine exhaust air flows through the turbocharger turbine, providing the motive force for its operation
  • Exhaust air leaves via a Flexible Connection to Exhaust Bellows From the exhaust bellows, air travels thru exhaust ductwork exits the EDG buildings
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14
Q

Describe the Unit 1 EDG One Engine Fail to Start Alarm.

A

Generated if the ΔT between Turbocharger Cylinder Exhaust temperatures differ by:
* 200°F

“OVERCRANK” alarm generated

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15
Q

Describe the Unit 2 EDG One Engine Fail to Start Alarm.

A

Generated if the ΔT between Turbocharger Cylinder Exhaust temperatures differ by:
* 220°F

Unit 2 EDG also has a local alarm.
* “One Engine Fail To Start”

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16
Q

Describe the Unit 1 EDG DG Air Start System.

A
  • 4 Air receivers broken into 2 subsystems (2 receivers per subsystem)
  • Each subsystem allows 5 starts of the associated EDG starting at T/S minimum values
  • EDG inoperable if 3/4 receivers
    < 135 psig
  • Each Engine has:
    2 Air Start Solenoids
    2 Air Start Relay Valves
    4 Air Start Motors – ** One Air start motor is enough to start the EDG**
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17
Q

Describe the Unit 2 EDG DG Air Start System.

A
  • 4 Air receivers broken into 2 subsystems (2 receivers per subsystem)
  • Each subsystem allows 5 starts of the associated EDG starting at T/S minimum values
  • EDG inoperable if 3/4 receivers:
    < 129 psig
  • Each Engine has:
    2 Air Start Solenoids
    2 Air Start Relay Valves
    4 Air Start Motors – ** One Air start motor is enough to start the EDG**
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18
Q

What are the Unit 1 EDG Electric Air compressor Auto Starts?

A

< 180 psig - Air dryer must be ON for the compressor to start (Dryer Switch must be on. If off, power is removed to the auto start permissive)

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19
Q

What are the Unit 2 EDG Electric Air compressor Auto Starts?

A

< 150 psig – Air dryer must be ON for the compressor to start. Air dryer is powered (Green light on) only when electric compressor is operating

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20
Q

What are the EDG Electric Air compressor Auto Stops?

A

> 200 psig all receivers AND minimum of 10 min run

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21
Q

Describe the Unit 1 EDG Air Start Blocked Relay.

A

Stops pulsing starting air to the EDG if either engine is:
EDG Speed >200 rpm
OR
Lube Oil pressure >20 psig

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22
Q

Describe the Unit 2 EDG Air Start Blocked Relay.

A

Starting air stops if either engine is:
EDG Speed >100 rpm
OR
Cooling Water pressure >20 psig

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23
Q

Describe the EDG Air Start Sequence.

A

EDG Start Signal energizes “Air Start Solenoid” passing signal air to lower air start motor pinion-engages the engine cranking ring Boost air is also supplied by “Air Start Solenoid.” Engagement of lower motor pinion uncovers lower motor air-port to allow signal air pressure to upper air start motor pinion-engages the engine cranking ring. Engagement of upper pinion uncovers air-port to allow air to the “Air Relay Valve.” Both pinions must engage to allow air supply to the “Air Relay Valve” actuator “Air Relay Valve” ports starting air to the air start motors which spin turning cranking ring. “Air Start Solenoid” open signal removed after 1.8 seconds-solenoid to VENT position. Motor pinions disengage and starting air blocked from “Air Relay Valve.” After 0.2 seconds, “Air Start Solenoid” is re-energized and cycle repeats

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24
Q

What is supplied by the Unit 1 EDG Main Lube Oil Pump?

A

Sucks on the Strainer Sump and discharges to main engine LO manifold above crankshaft, Cools & lubricates the Turbocharger and Bearings

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25
Q

What is supplied by the Unit 2 EDG Main Lube Oil Pump?

A

Gen Bearings only. Unit 2 has AC & DC LO Pumps

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26
Q

Describe the EDG Piston Cooling Pump.

A

Sucks on the Strainer Sump, discharges to pistons for cooling and lubrication.

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27
Q

Describe the EDG Scavenging Pump.

A

High capacity pump supplies oil from the Main Engine Sump to Strainer Sump via a strainer, filter and Lube Oil Cooler.

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28
Q

Describe the operation of the Unit 1 EDG Soak Back Pump.

A

Runs continuously
 Supplies oil to Turbocharger Bearings

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29
Q

Describe the operation of the Unit 2 EDG Soak Back Pump.

A

Runs continuously
 Circulates oil thru the engine to maintain it warm.

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30
Q

Describe the operation of the Unit 1 DC Soak Back Pump.

A
  • Same purposes as the AC Soak Back Pump

 Auto starts on loss of power to AC Pump

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31
Q

Describe the operation of the Unit 2 DC Soak Back Pump.

A
  • Same purposes as the AC Soak Back Pump
     Auto starts on low AC pump discharge pressure.
32
Q

Describe operation of the Unit 2 AC & DC Turbo LO Pumps.

A

Supply oil to Turbo and Engine bearings
DC pump auto starts:
* On low AC Pump discharge pressure (<10 psig)

33
Q

Describe the operation of the EDG immersion heaters.

A

Maintains the engine >85F in standby.
Heat DG Cooling Water which heats lube oil via NC cooler.
De-energize on DG start signal
Normally maintain cooling water 125 – 155F

34
Q

What are the EDG Lube Oil Temperature Limits?

A

Normally 165-180 when engine is running
< 65ºF; Disable the engine. May Damage EDG
< 85ºF; Declare EDG OOS per T.S. 3.8.1 or 3.8.2.
< 85ºF; No Fast Start Allowed
≤ 90ºF; IDLE Start EDG/Warm L.O.
> 150ºF; Stop & Do NOT Restart for Testing until ≥ 3 hours

35
Q

Describe the operation of the Unit 1 EDG Lube Oil system when the EDG is shutdown.

A
  • AC Soak Back Pump is running
  • Do not run < 300 KW for > 30 minutes due to accumulation of unburned fuel in the exhaust lines.
  • Procedures state: If the EDG has been running at low loads (<700KW) for >4 ½ hours, then run the EDG for at least 30 minutes at a load >1850KW.
36
Q

Describe the operation of the Unit 2 EDG Lube Oil system when the EDG is shutdown.

A
  • AC Soak Back Pump is running
  • AC Turbo Oil Pumps are running
37
Q

Describe the Unit 1 EDG Diesel Oil Storage Tanks.

A
  • 2 tanks
  • Tech Spec Minimum Limit: 19,000 gallons
  • BOTH tanks - 7 days operation - one EDG
  • One hour at 3500 KW will consume approx 280 gallons fuel oil (~3 inches of level in DOST)
38
Q

Describe the Unit 2 EDG Diesel Fuel Oil Storage Tanks.

A

2 tanks
42,500 gallons T/S Limit
ONE tank - 7 days operation - one EDG
@ 3685 KW will consume 300 gallons (~ 3 inches)

39
Q

Describe the Unit 1 Diesel Oil Day Tanks Tech Spec required level.

A

Tech Spec Minimum Limit: 152 gallons:
* Allows 32 minutes of run time at 3500 KW.

40
Q

Describe the Unit 2 Diesel Oil Day Tanks Tech Spec minimum level.

A

Tech Spec Minimum Limit: 238 gallons
* 47 minutes of run time at 3685KW.

41
Q

Describe the Unit 1 EDG Diesel Oil Day Tank Fill arrangement.

A
  • A single Solenoid fill valve for both tanks
  • Opens @ <21”, and tank gravity fills if level is ≥ 15”
  • FOTP starts if level <15”, and FOTP stops @ 21”
  • High Level alarm (22.5”) / Low Level alarm (12”)
42
Q

Describe the Unit 2 EDG Diesel Oil Day Tank Fill arrangement.

A
  • Individual day tank solenoids fill valves.
  • If level is low (<22.5”) in any respective day tank, that individual tank fill valve will open and the F.O. Transfer Pump starts
  • When the respective tank level is restored to normal (> 32.5”), that tank’s fill valve will close. The FOTP will then stop (provided the other day tank fill valve is also closed).
  • High Level alarm (33.5”) / Low Level alarm (21”)
43
Q

Describe the operation of the Unit 1 EDG Fuel Oil System.

A
  • DC Fuel Oil Pump:
     Starts on EDG start signal and shuts off when EDG speed >200 rpm.
     Engine Driven FO Pump supplies fuel oil
  • Low FO pressure alarm – 20 psig
  • A&B Fuel Transfer Pumps – 480V MCC A7 / B7
  • Diesel Day Tank Fill Solenoids – 120VAC Power Panel fed from 480V MCC A7 / B7
  • Note: Placing the DFOT pump on recirculation renders the DFOST pump incapable of performing its design function, and would result in EDG INOPERABILTY
44
Q

Describe the operation of the Unit 2 EDG Fuel Oil System.

A
  • DC Fuel Oil Pump:
     DC pump operates continuously
     Engine Driven FO Pump supplies fuel oil as well
  • Low FO pressure alarm – 10 psig (Engine FO pump failure alarm)
  • A&B Fuel Transfer Pumps – 480V MCC A7 / B7
  • Diesel Day Tank Fill Solenoids – 120VAC Power Panel fed from 480V MCC A7 / B7
  • Note: Placing the DFOT pump on recirculation renders the DFOST pump incapable of performing its design function, and would result in EDG INOPERABILTY
45
Q

What are the 125 VDC EDG loads?

A

125VDC – Supplies:
(125 VDC Bus 1A & 1B -feeds A & B EDG respectively)
* Air start solenoids
* Initial field flash
* Governor control
* Voltage Regulator Control
* Tripping Power
* EDG Breaker Control Power
* DC Powered Pumps
Have to have same train of DC power for EDG to start.

46
Q

What happens when the Unit 1 EDG DC Knife Switch is opened?

A

Unit 1 EDG remove all EDG control power (Called the DC Control Power Knife Switch)

47
Q

What happens when the Unit 2 EDG DC Knife Switch is opened?

A

Unit 2 EDG removes power to air start solenoids only (Called the Air Start Disc Knife Switch)

48
Q

What effect does loss of DC have on EDG?

A

EDG will NOT START if shutdown – Air Start Solenoids; No field flash
EDG will NOT TRIP if running – Have to manually trip over-speed trip levers on both units

49
Q

What are the EDG Auto Start signals?

A

The EDG’s will start on either of these two signals:

1) Loss of Off-site Power (LOOP); or
2) Safety Injection (SIAS)

Notes:
* LOOP – Signal is generated by under voltage or degraded voltage schemes.
* SIAS signals are train dependent (i.e. ‘A’ train SIAS starts the ‘A’ EDG)

50
Q

Describe the Unit 1 LOOP U/V & Degraded Voltage Schemes.

A

Unit 1 – 4160V (A3/B3)

  • U/V – 2/2
  • D/V – 2/2

Unit 1 – 480V Load Center (A2/B2)

A2 or B2:
* D/V – 2/2 with a SIAS / CIAS / MSIS

51
Q

Describe the Unit 2 LOOP U/V & Degraded Voltage Schemes.

A

Unit 2 – 4160V (A3/B3)

  • U/V – 2/2
  • D/V – 2/3 with a SIAS

Unit 2 – 480V Load Center (A2/B2 & A5/B5)

A2 or B2:
* U/V – 2/3
* D/V – 2/3
A5 or B5:
* U/V – 2/3
* D/V – 2/3

52
Q

Describe what happens when a LOOP is sensed.

A

The following occurs on the affected 4160V bus (A3/B3):
* 3-2 tie breaker(s) open
* Loads shed - (CCW, HPSI, LPSI, CS, AFW, PZR Htr)
* EDG(s) start
* EDG Output breaker(s) close - when EDG is at rated speed & voltage
* EDG(s) operate in isochronous mode

  • If LOOP occurs and the EDG’s were initially shutdown – An emergency bus U/V condition is generated, the 3-2 breakers open, and the EDG’s auto start in the Isochronous & Unity Modes on LOOP auto start signal. The output breaker closure should occur within 10 seconds. Normal previously running loads will then sequence on based on their particular load block.
  • If LOOP occurs and the EDG’s were initially running - EDG trips on over-current, and is locked out. An emergency bus U/V condition is generated, the 3-2 breakers open. EDG trips must be reset locally. Once trips have been reset, the EDG will automatically start and the output breaker will auto close. Previously running loads are sequenced back on to the bus.
  • If LOOP occurs coincident with a SIAS and EDG was shutdown- An emergency bus U/V condition is generated, the 3-2 breakers open, and the EDG’s auto start in the Isochronous & Unity Modes on LOOP auto start signal. The output breaker closure should occur within 10 seconds. All loads required for the SIAS will sequence on based on their particular load block.
53
Q

Describe the EDG response to a SIAS signal.

A
  • If off-site power is available, and a SIAS occurs – The associated train EDG will start in the emergency mode, but the output breaker will not close because the safety related emergency buses do not lose power. All SIAS related loads start at once. EDG operates in the emergency mode until manual action is taken to reset SIAS and stop EDG
  • If EDG running paralleled to the grid, and a SIAS occurs - SIAS trips EDG output breaker open (trip applied for 1.2 seconds), but the output breaker will not re-close because the safety related emergency buses do not lose power. All SIAS related loads start at once. EDG operates in emergency mode until manual action taken to reset SIAS and stop EDG
  • If the EDG running as the sole source of power, and a SIAS occurs - SIAS trips EDG output breaker open (trip applied for 1.2 seconds). The emergency bus U/V occurs and the 4.16 KV 3-2 breakers open. Bus load sheds. Individual breakers open on UV. The EDG output breaker re-closes. Loads sequence on the bus based on their particular load block.
  • EDG Surveillance Run Nearing Completion with SIAS - EDG running on shutdown timer during the 10 minute cooldown at 450 RPM. Get SIAS EDG increases speed to 900 RPM and remains running unloaded with output bkr open.
  • EDG surveillance just started and EDG at idle speed and emer. signal comes in - Idle signal over-ridden EDG speed increases to 900 rpm. EDG will then respond accordingly if a SIAS or LOOP. Note: if Start control switch [master start control] is in Isolate, the auto start signals are blocked to the EDG.
54
Q

Describe the Unit 1 EDG Load Block Sequence.

A

EDG Load Block Sequence
* 0 seconds – CCW, CHG (except 1C), BAM Pumps
* 3 seconds - LPSI Pumps
* 6 seconds - HPSI Pumps
* 9 seconds - ICW Pumps - Biggest Load
* 12 seconds - Containment Spray Pumps
* 15 seconds - AFW Pump(s)
* 18 seconds - 1C CHG Pump (if SIAS present)
* 35 seconds - Fire Pump (Will not auto start on SIAS)

55
Q

Describe the Unit 2 EDG Load Block Sequence.

A

EDG Load Block Sequence
* 0 seconds – CCW, CHG, BAM Pumps
* 3 seconds - LPSI Pumps
* 6 seconds - HPSI Pumps
* 9 seconds - ICW Pumps - Biggest Load
* 12 seconds - Containment Spray Pumps
* 30 seconds - AFW Pump(s)

56
Q

Describe the EDG Diesel Shutdown Sequence.

A

Normal EDG Shutdown
* Normal start / stop EDG switch will not work unless the EDG Bkr is open
* Once EDG is unloaded and output breaker is open, Taking the EDG switch to “STOP” will:
 Ramp down the EDG speed to 450 rpm and starts a 10 minute cooldown timer.
 After 10 minutes, the EDG shuts down

57
Q

What are the Unit 1 EDG trips?

A

EDG TRIPS – “COREWOOD”: KNOW ALL OF THESE
C - Crankcase Pressure High: > 1” H2O
O - Overcurrent
R - Reverse Power (Motoring)
E - Excitation Low
W - Water Temperature High: 205 °F & EDG Speed > 200 rpm
O - Oil Pressure Low: < 17 psig & EDG Speed > 200 rpm
O - Overspeed: 1040 rpm {alarm and lockout enabled above 200 rpm}
D - Differential Current
* Each of these trips will:
 Immediately stop the EDG, and
 Actuate the Lockout Relay to prevent future starts
 LO Relay needs to be reset on the EDG local control panel before the EDG can be restarted.

    ******* Very Important ******* *	If EDG has been started by an emergency start signal, (i.e… LOOP or SIAS), all EDG trips are automatically bypassed with the exception of: 	Overspeed 	Differential Current *	If EDG had been shutdown by ANY of the above trips, the EDG will not start on an emergency signal without first resetting the lockout relay (condition causing the non-essential trip does NOT have to be clear!)
58
Q

What are the Unit 2 EDG trips?

A

EDG TRIPS – “COREWOOD”: KNOW ALL OF THESE
C - Crankcase Pressure High: > 1” H2O
O - Overcurrent
R - Reverse Power (Motoring)
E - Excitation Low
W - Water Temperature High: 205 °F
O - Oil Pressure Low: < 20 psig & EDG speed > 100 rpm
O - Overspeed: 1035 rpm – no minimum speed to enable alarm/lockout
D - Differential Current
* Each of these trips will:
 Immediately stop the EDG, and
 Actuate the Lockout Relay and Shutdown Relay to prevent future starts
 LO & SD Relays need to be reset on the EDG local control panel before the EDG can be restarted.

  ******* Very Important ******* *	If EDG has been started by an emergency start signal, (i.e… LOOP or SIAS), all EDG trips are automatically bypassed with the exception of: 	Overspeed 	Differential Current *	If EDG had been shutdown by ANY of the above trips, the EDG will not start on an emergency signal without first resetting the lockout & shutdown relays (condition causing the non-essential trip does NOT have to be clear!)
59
Q

Describe how to Clear a Unit 1 EDG LOCKOUT condition.

A

Reset the LOCKOUT RELAY on the EDG local control panel

60
Q

Describe how to Clear a Unit 2 EDG LOCKOUT condition.

A
  • First - Reset the Lockout Relay by pressing the pushbutton on the EDG local control panel, then
  • Second - Reset the Shutdown Relay by:
     Depressing the Emergency Shutdown Reset Pushbutton on the DG panel OR
     Depress the Reset pushbuttons on the engine skid.
    [NOTE: electrical trips on unit 2 actuate the lockout relay, which in turn actuates the SDR]
61
Q

Describe what the EDG Bus 86 Lockout Relay Blue light being on means.

A
  • Blue Light is normally ON means:
     Relay NOT Tripped
     125VDC relay power is available
     Relay continuity check is SAT.
  • Blue light flashing indicates relay is tripped.
62
Q

What is the danger of operating the EDG at low loads?

A

<300 KW for > 30 minutes is procedural limit), Builds up carbon deposits in the exhaust and can cause a fire. Sometimes called “souping”

63
Q

What are the inputs to the Unit 1 “Ready to Start” permissive?

A

Unit 1: “SNL”
 Speed < 200 RPM
 EDG Start Control N/I Switch in NORMAL (Input for RTGB only)
 Lockout Relay is RESET

64
Q

What are the inputs to the Unit 2 “Ready to Start” permissive?

A

Unit 2: “SNLMES”
 Speed < 500 RPM
 EDG Start Control N/I Switch in NORMAL (Input for RTGB only)
 Lockout Relay is RESET
 Master Control Switch in AUTO
 Exciter Control Switch in AUTO
 Shutdown Relay is RESET

65
Q

Describe operation of EDG RTGB Emergency Trip Pushbutton.

A
  • Unit 1 - Does NOT have Emergency Trip Pushbuttons on the RTGB
  • Unit 2 - Will NOT stop EDG if running on ESF signal, used to quickly stop EDG by bypassing the cooldown if something goes wrong during a surveillance run only.
66
Q

Describe operation of EDG Engine Mounted Emergency Trip Pushbutton.

A
  • Unit 1 - Always works since signal is sent to Overspeed Trip Mechanism and this is one of the trips that is never bypassed
  • Unit 2 - Will NOT stop DG if running on a Safeguards signal
67
Q

Describe operation of EDG Overspeed Trip Levers on the Engines.

A

Always works
* On both Unit 1 & 2 manual stops will shutdown the EDG after a cooldown of 10 mins while at ~450 rpm (or immediately if Emergency Shutdown is used) by energizing the governor shutdown solenoid to dump governor oil to its sump allowing the fuel rack to go to no fuel position.

68
Q

Describe how to manually stop an EDG running on an ESFAS signal.

A
  • Unit 1: Trip the Overspeed Trip Levers OR Depress the Engine Mounted Emergency Trip Pushbutton on one engine.
  • Unit 2: Trip the Overspeed Trip Levers on one Engine
69
Q

Describe what happens to the EDG when the 3-2 Tie Breaker opens.

A
  • Sets Gov mode to Isochronous
  • Starts EDG
  • Allows EDG breaker to close (if N/I switch in NORMAL),
  • Sets VR (Non-Droop)
  • Trips 2-3 tie
  • Blocks Non Emergency trips
  • Taking the RTGB 101[201] SSS to the TIE-A3(B3) Position allows for manual speed control
70
Q

Describe the EDG response to a Vital 4160V Bus Lockout.

A

Bus X-Tie Breakers Open, EDG starts but breaker will not close until the bus lockout is cleared

71
Q

Describe the EDG response to a Loss of DC Power.

A
  • EDG will NOT Start
  • Air start Motor Solenoids fail closed
  • No DC to flash generator field, No indication
  • No Governor Control Power.
  • No power to trip EDG (Shutdown only via Auto or Manual, at the OST device, Overspeed trip)
  • No power to DC powered EDG pumps.
72
Q

Describe EDG Breaker Closure Logic.

A
  • Local Closure - Normal / Isolate Switch in Isolate, Local breaker switch placed in close
  • Remote Closure - (RTGB), Normal / Isolate Switch in Normal, Sync Select Switch in “DG” position, RTGB Output breaker Switch to close
  • Auto Closure - 4160 Bus Load Shed signal (LOOP), SS in Normal, CS in Normal, 3 to 2 Tie Breaker Open Signal
73
Q

Which are the Appendix R designated trains?

A

Unit 1: Train B
Unit 2: Train A

74
Q

Describe the operation of the EDG Output Breaker Normal / Isolate Switches.

A
  • Place in Isolate prior to closing breaker locally
  • Allows Breaker Control with Switch on Breaker Door
  • Prevents Breaker from closing on an ESFAS signal
  • Mechanical Close Button on the Breaker itself ALWAYS works
  • 1B & 2A EDG switches insert a new set of appendix R control power fuses
75
Q

List Important EDG Procedure Precautions / Limitations.

A
  • Starting the Diesel with lube oil temperature less than 65°F will result in serious damage to lube oil system components.
  • In an emergency with lube oil temperature less than 65°F and NO other power source available to the vital buses of that unit, then the EDG should be idle started and warmed up for 2 minutes before going to rated speed and being released for service.
  • Declare EDG inoperable if oil temperature is less than 85°F.
  • Do not fast start the EDG if oil temperature is less than 85°F.
  • If engine oil temperature decreases to less than 90°F as determined by calibrated pyrometer, the EDG should be idle started (450 rpm) for warmup and the standby heaters operation verified.
  • For an emergency start, the EDG requires NO support from other plant systems except 125 VDC from its respective DC bus. Long term operation, greater than 1 hour, requires 480 VAC power for the fuel transfer system.
  • If a Unit 2[1] EDG is removed from service for an extended Allowed Outage Time (AOT) of greater than 72 hours, a Unit 1[2] EDG shall be removed from service only for maintenance required to ensure or restore OPERABILITY of the Unit 1[2] EDG and for a period NOT to exceed 72 hours per ADM-17.16, Implementation of the Configuration Risk Management Program.

block 1 (4 decks)

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