Containment Purge (CP)

Question 1

The Containment Purge system is used to maintain nitrogen cover gas on the steam generators during wet layup conditions.

True of False?

Answer 1

True

The GA System uses a regulator to releases nitrogen into the CP System during the time that a cover gas is being maintained within the Steam Generators.

Question 2

What is the pressure band for Containment pressure per Tech Spec 3.6.4, Containment Pressure?

Answer 2

3.6.4 Containment Pressure

LCO 3.6.4 Containment pressure shall be > -0.3 psig and < +2.5 psig.
APPLICABILITY: MODES 1, 2, 3, and 4.
ACTIONS - COND ITION REQUIRED ACTION COMPLETION TIME 1 hour
A. Containment pressure not within limits.
A.1 Restore containment pressure to within limits.

Question 3

What is the power supply for the Refueling Purge Containment Isolation Valves?

Answer 3

Refueling Purge CIVs (4)
* 42” ducting
* 2 supply / 2 exhaust duct CIVs (motor operated)
* Power: PHA/PHB
* Modes 1-4:
o Closed / de-energized / isolated with blind flange
o Not qualified for auto closure under DBA conditions. (LCO 3.6.3 bases)
* Auto isolates (CIAS or CPIAS)
o Signals can be overridden

Question 4

What is the cooling source for the Refueling Purge Normal AHU’s?

Answer 4

Refueling Purge Normal AHU (2)
* Oil impingement air cleaner, cooling coils, heating elements, and 2 (50% capacity) fans
* Cooled by Normal Chilled water (WC)

Question 5

What is the primary concern with ventilation changes if PCN-V118 is open?

Answer 5

• If transfer valve (CTMT to SFP) is open, water level changes could occur during ventilation changes.

Question 6

What has a higher capacity Refueling Purge Normal Suppy or Exhaust Fans?

Answer 6

Refueling Purge Normal Exhaust Fans (2)
* Higher capacity than supply fans
* Maintains CTMT at a negative pressure.

Question 7

What is the Open interlock for Power Access Purge Supply Containment Isolation Valves (4A/5A)?

Answer 7

• PKA/PKB
• Fail closed
• Operated in pairs from 2 MCR HSs
• Normally energized and closed
• Air is normally isolated to outside CIVs (4A/5B)
• Auto isolate (CIAS or CPIAS)
  o Isolate < 12 seconds (3.6.3 bases)
  o Signals can be overridden
• Inlet CIVs (4A/5A)
  Open interlock
  CTMT pressure < 0.03 psig (1” H2O)
   (PT-492A/493B)
  o Prevents damage to supply fan duct due to high pressure.