VA

Question 1

What system supplies cooling water to the ABSUs (Auxiliary Building Supply Unit)?

Answer 1

YV

Question 2

What signals will shutdown the ABSUs?

Answer 2

• Associated ABUFXF stops
• Motor overload
• Smoke detectors (Shutdown both ABSUs)

Question 3

With its control switch in “AUTO”, when does the ABSU automatically start?

Answer 3

When its associated unfiltered exhaust fan starts (manually or automatically), following a one-minute delay to allow inlet dampers to open (damper position follows supply unit operation)

Question 4

What signals will shutdown the ABUXF (Auxiliary Building Unfiltered Exhaust Fan)?

Answer 4

• Shutdown of the ABFXF
• EMF-35, 36 Trip 2
• Safety Injection signal

Question 5

What signals will start the ABUXF (Auxiliary Building Unfiltered Exhaust Fan)?

Answer 5

When VC/YC is transferred to LOCAL (Train related, A Train VC/YC to local will start ABUXF-1A and -2A)

Question 6

What signals will start the ABFXF (Auxiliary Building Filtered Exhaust Fan)?

Answer 6

• VC/YC to LOCAL (Train related, A Train VC/YC to local will start ABUXF-1A and -2A).
• Safety Injection Signal (Train Related – Unit 1 A Train Safety Injection will start ABFXF-1A and -2A).

Question 7

What signals will STOP the ABFXF (Auxiliary Building Filtered Exhaust Fan)?

Answer 7

• Motor overload
• Tornado actuation

Question 8

What signals will place VA in filter mode?

Answer 8

• Trip 2 signal on Radiation Monitor 0-EMF-41. (Unit and Train Independent - 1A, 1B, 2A, and 2B Filter Units will all realign to the filter mode.)
• Trip 2 signal on the Unit Vent Stack Radiation Monitor, 1(2) EMF-35, 36. (Unit Related – 1EMF-35 will realign 1A and 1B Filter Units to the Filter Mode)
• Safety Injection Signal (Train Related – Unit 1 Train A Safety Injection will realign 1A and 2A Filter Units to the Filter Mode)

Question 9

What system provides the normal cooling to the ASPSUs? What is the back-up source?

Answer 9

Normal is KC
Backup is RN (Manually aligned)

Question 10

What signals will start the ASPSU (Auxiliary Shutdown Panel Room Supply Units)?

Answer 10

Blackout (Unit and train related)
Safety injection - will initially trip off the ASPSU, and then the ASPSU will be restarted by the load sequencer.

Question 11

Will the VA system go to LOCA mode of operation if tornado isolation is activated?

Answer 11

No

Question 12

What occurs in the VA system when VC/YC is taken to “Local”?

Answer 12

• Starts both Units’ train related filtered exhaust fans. All trips are blocked.
• Starts both Units train related unfiltered exhaust fans (no permissive needed from filtered exhaust fans, all trips are blocked except motor overcurrent) which results in the associated supply fans starting which also has all its trips blocked except motor overcurrent.

Question 13

What occurs in the VA system when 0EMF-41 (Auxiliary Building Radiation Monitor) Trip 2 comes in?

Answer 13

Aligns all of Unit 1 and Unit 2 Exhaust Filter Units (4 total) to the Filter Mode of Operation

Question 14

What occurs in the VA system when EMF-36,36 Trip 2 (Unit Vent Radiation Monitors) comes in?

Answer 14

Trips the unit related unfiltered exhaust fans and aligns the unit related Filter Exhaust Units to Filter Mode of Operation. (i.e. 1EMF-36 trip signal trip ABUXF-1A and -1B and realigns 1A and 1B Filters to Filter Mode.)

Question 15

What occurs in the VA system when Tornado Actuation button is depressed?

Answer 15

• ABFXF trips
• ABUFXF trips due to trip of ABFXF
• ABSU trips due to trip of ABUFXF
• ABUFXF discharge tornado dampers close
• ABSU inlet tornado dampers close
• Tornado dampers close to isolate the Auxiliary Building from the Auxiliary Service Building (Unit 1 Train A switch)
• VC/YC pressure filter train supply check dampers close