Blackout

Question 1

What are entry conditions for blackout?

Answer 1

All 4160V buses de-energized

Question 2

When is ELAP declared and transition made to FDS-001 Unit 1 Extended Loss of AC Power to address feedwater?

Answer 2

If failure of P-7A occurs and one of following

1) 1 hour elapsed since blackout occurred.
2) Evident that blackout will exceed 1 hour
3) directed by TSC, EOF, or SM

Question 3

What actions are taken to minimize RCS losses?

Answer 3

1) Close CV-1223
2) RCP Bleedoff alternate path to close and manually close CV-1221 and CV-1274
3) Hot leg sample isolation closed

Question 4

What actions are taken for a LOSCM during blackout?

Answer 4

Perform RT-5 and if RV head void indicated then perform rapid cooldown.

Question 5

What actions are taken if offsite power is recovered and not degraded?

Answer 5

Perform Att 2 (recovery from blackout breaker alignment and UV relay defeat) if Att 1 was performed and energize applicable buses.

Question 6

What major steps are performed when offsite power restored to vital buses?

Answer 6

Ensure SW pumps start, Restore P-7B (If no EFW still available perform RT-4), return heaters to service > 55”, RT-9 and 22 for ICW, restore MU and SI, Restore RCPs etc

Question 7

What steps are performed if one hour elapsed since blackout or projected to exceed 1 hour?

Answer 7

Request TSC to supply power from unit 2 to unit 1 via AAC generator bus 2A9 and declare ELAP.

Question 8

What major steps are performed for blackout (Step 39)?

Answer 8

Purge generator, Break vacuum, ADVs on handjack

Question 9

What following problems might occur if power recovered from degraded offsite power?

Answer 9

(Caution Pg 28)

• Motors might trip on overload, overheat due to high running currents or stall
• MCC starter might not pick up energize loads
• AC Aux relays might not pick up to provide interlock or load energization features

Question 10

What actions are taken to restart equipment during degraded voltage condition?

Answer 10

• Ensure flowpath
• Review procedures to ensure pump services available
• Consider closing discharge valve to reduce starting current
• Dispatch operator to close dc control breaker and place it in remote
• Coordinate with U2 for starting loads on SU2
• Start one motor at a time and monitor winding temps

Question 11

What major actions are taken in Att 1 (Blackout breaker alignment and UV relay Defeat) in blackout?

Answer 11

• Place A-1, H-1, H-2, A-2 breakers in local and open breaker
• Pull fuses in same breakers for UV close permissive interlocks and UV trips
• Open A-3 and A-4 breakers and Test switches for UV trips
• Open B-6 and B-5 breakers
• Open breakers on MCCs 57,55,56,51,52,53,61,62,63,65