AOP-3 "Main Feedwater Transients"

Question 1

AOP-3 entry conditions

Answer 1

• EK-0143 “FW Pump P1A Turbine K7A Trip”
• EK-0149 “FW Pump P1B Turbine K7B Trip”
• EK-0148 “FW Pump P1A Lo Suction Flow or Lo Disch Press” (2500 gpm or 800 psig)
• EK-0154 “FW Pump P1B Lo Suction Flow or Lo Disch Press” (2500 gpm or 800 psig)
• EK-0146 “FW Pump Lo Suction Press Channel Trip” (250 psig)
• EK-0160 “Fdwtr Pump Lo Suction” (305 psig)
• EK-0155 “Condensate Pump Trip”
• EK-0157 “Condensate Pump P2A Discharge Lo Pressure” (390 psig)
• EK-0163 “Condensate Pump P2B Discharge Lo Pressure” (390 psig)
• EK-0170 “Heater Drain Pump Trip”
• EK-0961 “Steam Generator E-50A Hi Level” (84.7%)
• EK-0962 “Steam Generator E-50A Lo Level” (55%)
• EK-0963 “Steam Generator E-50B Hi Level” (84.7%)
• EK-0964 “Steam Generator E-50B Lo Level” (55%)
• Indications of a Main Feedwater transient in progress
• Condensate Cleanup System leak
• Main Feedwater piping rupture
• Heater Drain Pump malfunction

Question 2

AOP-3 automatic actions

Answer 2

• CV-0608, Moisture Separator Drain Tank T-5 Level Control fully opens (Low Feedwater suction pressure 270 psig)
• Main Feed Pumps, trips (Low Feedwater Pump suction pressure 250 psig after a 3 second time delay)
• AFAS initiation (S/G level of 30%)
• Reactor trip (S/G level of 28%)
• CV-0701, E-50A Feed Regulating Valve, closes by high level override (84.7%)
• CV-0703, E-50B Feed Regulating Valve, closes by high level override (84.7%)

Question 3

AOP-3 reactor trip criteria

Answer 3

• Either S/G level lowers to 30%
• No Main Feed Pump operating
• EK-0961 “Steam Generator E-50A High Level” is alarming, AND S/G level(s) are less than 60% and lowering
• EK-0963 “Steam Generator E-50B High Level” is alarming, AND S/G level(s) are less than 60% and lowering
• Any operating Main Feed Pump trips (> 80% power)
• CV-0711, Feed Pump P-1A Recirculation Valve fails open (> 80% power)
• CV-0710, Feed Pump P-1B Recirculation Valve fails open (> 80% power)
• Either S/G level > 90% AND the high level override has not lowered feedwater flow (>= 15% power)
• Either S/G level > 95% (>= 15% power)

Question 4

AOP-3 turbine trip criteria

Answer 4

• Either S/G level > 90% AND the high level override has not lowered feedwater flow (< 15% power)
• Either S/G level > 95% (< 15% power)

Question 5

AOP-3 immediate actions

Answer 5

• Take manual control of the following as necessary ot restore/stabilize S/G levels:
  - Feed Reg Valves
  - Feed Reg Bypass Valves
  - Combined Feed Pump Speed Control
  - Individual Feed Pump Speed Controls

-If either S/G high level alarms are in, then verify S/G levels >= 60% and <= 90%