Manual Trips

Question 1

List Manual Turbine Trip Criteria.

Answer 1

• Bearing 1 - 6 metal > 250°F
• Bearing 7 - 8 or Thrust Bearing metal > 225°F
• Any bearing oil drain > 180°F
• Emergency Oil Trip Press < 1000 psig
• Unbalanced Phase Current, AM-880 >20% (pegged high), generator damage after 20 sec
• SG Level > 80 [75] % NR
• Turbine Vibration > 14 mils
• Turbine AVG Hot Gas Temp > 113°C
• Condenser Back Pressure
• > 8.5 inHgA
• Δ > 2.5 inHgA

Question 2

List Turbine Auto Trips.

Answer 2

• Overspeed > 1998 rpm
• Bearing Oil Press < 6.0 psig
• Thrust Bearing Position > 40 mils
• Exhaust Hood Spray > 250°F
• Condenser Vac: 8.859 inHgA
• Thrust Bearing Position: +40 mils
• ET Trip Header Press: 1000 psig
• SG Level > 90 [81]% NR
• Rx Trip Switchgear Undervoltage

Question 3

List Manual Reactor Trip Criteria.

Answer 3

RCS Leak > available charging pump capacity
SG Level < 40% NR due to:
* Loss of Main Feed Pump
* Loss of Cond Pump
* MFP Recirc failing open
* Feed Reg Valve problems
Main Steam Leak, 2 of 4 Rx Pretrips:
* Power High
* Cont Press >2.5 psid
CEAs:
* Motion with Rod Control in Off
* >1 CEA: misaligned >15” or dropped
Instrument Air Press < 60 psig
Traveling Screen 40” Δ & CW Pump Throttled

Question 4

List RCP Manual Trip Criteria (AFTER Tripping Rx)

Answer 4

Motor Stator > 311°F
Motor Amperes > 600 amps
[Motor Vibration > 14 mils]
Pump Vibration > 25 mils
CBO Flow is 0 gpm for > 30 minutes
CBO or Lower Seal Cavity Temp:
* 300°F
* 250°F for > 10 minutes
CCW Flow is LOST for > 10 minutes
Seals: 3 Failed
Guide Bearings > 185°F
Thrust Bearings > 200°F
Valid Oil Reservoir Level Off Scale (+ 5”)
Main Spray Valves, PCV-1100E or F stuck open

Question 5

List Rapid Downpower Criteria.

Answer 5

RCS Leak: If requires T.S. shutdown
SGTL > 100 gpd (<50% in 1 hr, M3 next 2 hrs)
SG Lowering Levels:
* Loss Heater Drain Pump (~90%)
* Heater Tube Rupture (~90%)
Main Steam Leak in Cont Press >1 psig/hr
Instrument Air Press < 75 psig
RCP due to:
* Oil Reservoir Leak > 0.5”/hour
* Seals: 2 Failed
* CBO Flow > 3 gpm
Turbine due to:
* Loss of both Isophase fans (<15.99 KAmps)
Cold Gas maintain > 50.7°C due to:
* TCW problems
* ICW problems
TCW leak into H2 Cooler (<80%)
* Stator Temp (<80%)
* MAX HOT GAS DELTA REDUCE VALUE
* MAX HOT GAS DELTA TRIP VALUE
Loss of RCB Cooling Fans:
* HVE-21A & B, CEDM
* HVS-2A & B, Rx Cavity
* HVE-3A & B, Rx Support
* HVS-1A > D & Cont Temp > 120°F
Traveling Screen 20” Δ