SSPS

Question 1

What does the Bistable Test Switch in test do?

Answer 1

• Gives SSPS a trip signal for both trains
• Used to place bi-stable in “Trip” (if it fails in its non trip direction)

Question 2

What does the RPS Bypass Switch in bypass do?

Answer 2

• Prevents getting a trip signal
• Puts power to logic bay regardless of input, allowing you to test the input drawer (using bistable test switch) without chance of causing an actuation.

(keyed switch)

Question 3

What powers Train A Slave Relays?

Answer 3

CRID I
(120v AC)

Question 4

What powers Train B Slave Relays?

Answer 4

CRID IV
(120v AC)

Question 5

What power failure will prevent an actuation of ESF equipment?

Answer 5

• A loss of either CRID I or CRID IV (Train Specific) will prevent an ESF actuation
• (Master and Slave Relays are normally de-energized. Loss of a supplying CRID won’t allow the SLAVE Relays to energize on a trip)

Question 6

Where does the SSPS General Warning come from?

Answer 6

Logic Cabinets

Question 7

What will cause an SSPS General Warning?

Answer 7

• Bypass Bkr Closed
• Output mode selector switch in test
  As well as:
• Loss of 48v DC or 15v DC (CRID lost)
• Input Error inhibit switch in INHIBIT
• Multiplexer switch in INHIBIT
• Any circuit board removed except isolation boards
• Permissive switch out of OFF
• Memories switch out of OFF
• Grounded return fuse blown

Question 8

A loss of which SSPS power supplies will cause a Rx trip?

Answer 8

Both 15v DC pwr supplies
OR
Both 48v DC pwr supply

Question 9

How do the Trip Coils on the RTBs cause the Reactor Trip Breakers to trip?

Answer 9

Energize to trip

Question 10

How do the UV Coils on the RTBs cause the RTB to trip?

Answer 10

Deenergize to Trip (loss of 48v DC)

does NOT need control power

Question 11

How do the Rx Trip switches trip the Rx?

Answer 11

Either Rx Trip Switches will energize both Rx Trip and Bypass Breaker Trip Coils (all 4)

Question 12

What does the Shunt Coil do for the RTB?

Answer 12

Energizes the trip coil
(RTBs only, they are not on the Rx Trip Bypass Bkrs)

uses control power

Question 13

If both Rx Trip Bypass Bkrs are closed in at the same time, what will happen?

Answer 13

Trips both Bypass Breakers

Question 14

If you put bistable test switch to test, what happens?

Answer 14

Trips (actuates) bistables with the exception of CTS

(CTS bistables are bypassed. They are energize to actuate)

Question 15

What is provided power directly from the SSPS Input Bays?

Answer 15

Input Bay Direct Feeds

Question 16

What are the Input Bay Nondirect feeds powered by?

Answer 16

Protection racks

Question 17

Is the General Warning light visible with the Logic Cabinet door closed?

Answer 17

Yes, it is visible on the Logic Bays

Question 18

Which RTB and Rx Trip Bypass Bkrs are tripped by Train A SSPS?

Answer 18

• Rx Trip Bkr A
• Rx Trip Bypass Bkr B

Question 19

Which RTB and Rx Trip Bypass Bkrs are tripped by Train B SSPS?

Answer 19

• Rx Trip Bkr B
• Rx Trip Bypass Bkr A

Question 20

What will happen if you get a General Warning on Both Trains of SSPS?

Answer 20

Reactor will trip

Question 21

What does the Isolation Amplifier do?

Answer 21

Ensures failure in control system does not cause the same issue in the protection system

Question 22

If the Output Mode Selector Switch is taken to test, what happens?

Answer 22

Disables all slave relays for an entire train
(by replacing 120 vAC power with 15 vDC)

Question 23

What does the Input Error Inhibit Switch do?

Answer 23

Keeps logic cards from sensing a change in input. The signals will NEVER get to the logic cabinet, which allows testing.

SI Switch for that Train WILL work

Question 24

What does the MULTIPLEXOR DO?

Answer 24

Only goes to status lights, alarms, PPC

Question 25

What are the inputs to OTΔT? What does it protect from?

Answer 25

RCS ΔT, Tavg, AFD and Pzr Pressure (Protects from DNB)

Question 26

What are the inputs to OPΔT? What does it protect from?

Answer 26

RCS ΔT and Tavg (Protects from KW/ft) | No P in OPΔT!!!

Question 27

What's the only ESFAS trip that cannot be reset with a trip signal still standing?

Answer 27

Steamline Isolation

Question 28

What is the high level flowpath for SSPS from a signal in the field to the pump and valve actuations?

Answer 28

Question 29

If CRID 1 is lost, what is the significance for SSPS?

Answer 29

Train A Slave Relays are lost, so auto actuations for that train won’t work. Train A SI Switches will NOT work. Pumps and valves can be aligned manually

Question 30

If CRID 4 is lost, what is the significance for SSPS?

Answer 30

Train B Slave Relays are lost, so automatic ESF actuations won’t happen. Train B SI switches will NOT work. Pumps and valves would have to be aligned manually

Question 31

The following conditions exist: - Containment pressure instrument Channel #1, 2-PPP-303 (PT-937) declared inoperable. - Required actions per 2-OHP-4022-013-011 Containment Instrumentation Malfunction have been completed. - Required Technical Specification Actions have been taken for Channel #1, 2-PPP-303 (PT-937) What is the REMAINING coincidence for the SAFETY INJECTION ACTUATION and CTS ACTUATION?

Answer 31

SI = 2/3 CTS= 2/3 (The CTS Actuation Bistable is placed in the BYPASSED condition to prevent inadvertent actuation. This changes the remaining channel coincidence to 2/3 instead of the previous 2/4. Only 3 channels (Channels 2, 3, & 4) feed the SI Actuation This channel does NOT feed SI so the SI coincidence remains at 2/3)

Question 32

Given the following plant conditions: - Unit 2 is at 100% power - Containment pressure instrument Channel #3, 2-PPP-301, declared inoperable - Required actions per 2-OHP-4022-013-011 CONTAINMENT INSTRUMENTATION MALFUNCTION have been completed CRID 2 has just lost power. Explain the impact on the Safety Injection system.

Answer 32

Train 'A' and 'B' Safety Injection actuation logic were satisfied. Both Trains equipment will automatically actuate.

Question 33

Will the Manual SI Switches work if the Output Mode Selector Switch is in TEST?

Answer 33

No! Must be done manually if required.

Question 34

Will the Manual SI Switches work if the Input Error Inhibit Switch is in INHIBIT?

Answer 34

Yes!

Question 35

Does a loss of 250 vDC control power result in a Reactor Trip? Why or why not?

Answer 35

YES! The trip is a result of loss of DC power to the underfrequency relays that sense a Low Frequency condition that requires a reactor trip.

Question 36

What happens if you lose CRID 1 and 2?

Answer 36

Both Train A 48 and 15 vDC power supplies go away. Reactor trips

Question 37

What does the Mode 5 and 6 switch do?

Answer 37

Maintains 120 vAC to slave relays for CVI relays, even with the Output Mode Selector Switch in Test.

Question 38

What is the normal source of power to the Rod Control Logic Cabinets?

Answer 38

120 vAC stepped down from 260 vAC Rod Drive MG Set Output