P81 - HPCS Diesel Generator

Question 1

How can diesel be started in the maintenance mode?

Answer 1

automatic and remote starts are disabled, but may be started locally

Question 2

what are the start and stop auto signals for the fuel oil pump in reference to the day tank?

Answer 2

18.8” - 41”

Question 3

What should the exhaust temperature maintain between the 2 engines?

Answer 3

Within 200ºF of each other (111ºC)

Question 4

What is the minimum air pressure allowed by the tech spec?

Answer 4

175 psig

Question 5

what’s the tech spec limit for fuel level? How long will this allow it to run?

Answer 5

44,616 gallons (7 days) or >6.2 feet

Question 6

What temperature does the temp control valve maintain?

what temp does the jacket water heater maintain?

Answer 6

180ºF

140-155ºF

Question 7

what is the power supply to the motor driven air compressor?

Answer 7

12B51

Question 8

When does the motor driven compressor cycle on and off?

Answer 8

ON - 220 psig

OFF - 235 psig

Question 9

When does the diesel driven compressor cycle on and off?

Answer 9

ON - 190 psig

OFF - 225 psig

Question 10

If diesel is carrying the bus alone with NO offsite power, what happens if LOCA signal is received?

Answer 10

Nothing, the diesel keeps the bus

Question 11

What is the purpose of the scavenging pump?

Answer 11

Runs durin operation to filter and cool lube

Question 12

what is the purpose of the soak back pump?

Answer 12

Circulate oil from lube oil pump to turbo bearing to cool bearing after oil system has shut down. It circulates through lube oil cooler to pick up heat while in STBY

Question 13

What are the Electrical Trips?

Answer 13

RLOG

• Reverse power
• Loss of excitation
• Overcurrent with voltage restraint
• Generator differential

Question 14

What are the mechanical trips?

Answer 14

• Overspeed 1035 rpm
• Low lube oil pressure <20psig
• High jacket water temp >205ºF
• High crankcase pressure 1” water column

Question 15

How long will the diesel attempt to start after receiving a start signal?

Answer 15

5 seconds

Question 16

When is air supply cut off when starting

Answer 16

150 rpms

Question 17

When can the starting motors be re-engaged?

Answer 17

< 50 rpms

Question 18

How can starting logic be reset after a failed start?

Answer 18

Engine lockout pushbutton must be depressed

Question 19

How does diesel respond to a LOCA signal? (with no other signal)

Answer 19

Diesel will start and wait as long as BUS still has voltage. breaker cannot be closed manually or automatically with only LOCA signal present

Question 20

What’s the tech spec rating of DIV 3

Answer 20

3300 kw

Question 21

What trips are in on a LOCA and BUV signal?

Answer 21

Generator differential and overspeed

Question 22

How does diesel shutdown on normal shutdown?

Answer 22

Engine runs for 10 minutes @ 450 RPMs to allow engine to cool prior to shutdown

Question 23

How does diesel shutdown in emergency shutdown?

Answer 23

Shuts down immediately

Question 24

What is the purpose of the Div 3 diesel?

Answer 24

provide backup power to HPCS

Question 25

How long can diesel run on Day tank?

Answer 25

2 hours

Question 26

what is the tech spec limit for fuel oil day tank?

Answer 26

220 gallons?

Question 27

What initiation logic can be reset even while it is still sealed in?

Answer 27

Drywell pressure

Question 28

What happens if Diesel detects a BUV or LOCA during the 10 minute cooldown?

Answer 28

increases back to 900 rpm, but will not take the BUS until voltage reset pushbutton is depressed