Auxiliary Feedwater System Alarms Flashcards
EK-0137, “AFAS-FOGG SUBSYSTEM TRIP”
EK-0137, “AFAS-FOGG SUBSYSTEM TRIP”
indicates that either a sensor channel has tripped or an actuation channel has tripped.
Check AFAS status array to find out which channel or actuation circuit has tripped.
If AFAS has occurred, check AFW system operation for proper response
EK-0138, “AFAS-FOGG SUBSYSTEM BYPASSED”
EK-0138, “AFAS-FOGG SUBSYSTEM BYPASSED”
his alarm indicates either:
- A level sensor channel is bypassed
- An actuation channel is blocked via push buttons on AFAS-FOGG Channel ‘A’ or ‘B’ modules on Panel C-11. Note that use of these buttons is not in any plant procedure.
- AFAS actuation is blocked via test switches at C-187.
- If an actual AFAS occurs, block is automatically removed and the signal processed
- CV-0736 or CV-0737 is open
Check AFAS status array to determine which channel is bypassed or actuation circuit is blocked.
Check Panel C-187 to determine reason for bypass or block
EK-0139, “AUX FEEDWATER PUMP TRIP”
EK-0139, “AUX FEEDWATER PUMP TRIP”
This alarm indicates that P-8A or P-8C control switch is in the “after-close” position but the breaker is open.
Check P-8A or P-8C status lights, discharge pressures on Panel C-01and AFW Status Array, flow on Panel C-11.
EK-0140, “AUX FWP LO SUCTION PRESSURE”
EK-0140, “AUX FWP LO SUCTION PRESSURE”
This alarm indicates that any of the AFW pumps have tripped on low suction pressure.
Check P-8A or P-8C status lights, discharge pressures on Panel C-01and AFW Status Array, flow on Panel C-11
EK-1108, “CONDENSATE STORAGE TANK T-2 HI-LO LEVEL”
EK-1108, “CONDENSATE STORAGE TANK T-2 HI-LO LEVEL”
Sensor:
- LIA-2021, T-2 Level Alarm
- LIA-2022, T-2 Level Alarm
Trip Setpoints:
- High: 98%
- Low: 73%
For a low level, this indicates that CV-2010, Condensate Storage Tank T-2 Makeup, has not opened or there is a problem with the Demineralized Water supply system.
Check T-2 level indication on panel C-13
EK-1108, “CONDENSATE STORAGE TANK T-2 HI-LO LEVEL” additional actions
If level lowers to 7.5% all AFW pumps must be manually tripped if running and placed in MANUAL to prevent start on AFAS.
IF in ELAP, THEN do not trip P-8B, Steam Driven Auxiliary Feedwater Pump until T-2, Condensate Storage Tank level reaches 0%.
What is the ILT-2 light on the C-150 panel?
This is an amber warning light only to notify the operator that P-8A/B suction pressure is 7.0 psig. Note that Low suction pressure trip setpoint is 6.7 psig. P-8B will not trip on low suction pressure when being operated from Panel C-150
