INSTRUMENT/STATION AIR Flashcards
(19 cards)
What is the required pressure for two-hour air to satisfy Decay Heat Removal Tech Spec?
1500#
What is the pressure range that should be maintained for two-hour air prior to RCS >250°F?
1700-2500#
What precaution should be taken when depressurizing IA upstream of IA/CW cross-tie?
Ensure proper isolation to prevent CW from back-flowing into the IA system.
What are the trip conditions for IA-P-4?
High outlet temperature (428°F) and high inlet temperature (158°F).
At what pressure does IA-Q-2 Dryer Bypass Valve (IA-V-2133) open?
75# lowering.
What happens to IA-Q-2 Dryer Bypass Valve when pressure is restored?
It stays open if in AUTO.
What is the pressure control range for IA-P-1A/B in AUTO and HAND?
AUTO: 95-105#, HAND: 100-110#.
What is the function of IA-V-2104A/B?
Opens at 85# to allow IA-P-1A/B to supply the header.
What happens to IA-V-2104A/B on loss of power?
It fails open and must be manually closed after opening.
At what pressure does SA-P-1A/B auto-start?
90# lowering.
At what pressure does IA-V-1 (SA to IA cross-connect) open?
80# lowering.
What is the function of IA-P-2A/B?
Supplies CO-V-5/7/8, FW-V-16/17A/B, and MS-V-3s.
At what pressure do IA-V-1533/1542 block valves open?
70# lowering.
What is the purpose of IA-Q-1?
It is the air dryer for IA-P-1A/B.
What happens at 60# bottle pressure in the two-hour air system?
IA-V-1625A/B vent valves open to relieve pressure, and IA-V-1626A/B 3-way valve isolates the IA header from critical valves.
What actions are taken at the 60# milestone per AOP-28?
Trip Rx, IA-V-26 closes to isolate non-essential IA loads, and IA-V-1626A/B isolates two-hour air from the header.
What happens to MS-V-3s if normal secondary side IA header is lost?
Control is maintained at 20% due to BUIA.
What happens if a leak occurs at MS-V-3 after IA-V-26 closes?
Pressure will continue to lower.
What happens to MS-V-3s if they are at 20% and the normal secondary side IA header is lost?
Control will be maintained at 20%.
