Protective Interlocks Flashcards
Describe the permissive, setpoint, coincidence, and function of P-4.
Reactor Trip
Rx trip and bypass breakers open
N/A
1. Trips main turbine
2. Feedline isolation with low Tavg (564F)
3. Prevents re-actuation of SI after manual reset
4. Transfers steam dumps from load rejection to plant trip
Describe the permissive, setpoint, coincidence, and function of P-6.
Source Range
IR greater than 10^-10 amps
1/2
Permits block of SR trip, HV off
Describe the permissive, setpoint, coincidence, and function of P-7.
At Power
P-10 or P-13
1/2
Automatically unblocks the following trips:
1. PZR low pressure
2. PZR high level
3. Low flow in more than one loop
4. RCP undervoltage
5. RCP underfrequency
Describe the permissive, setpoint, coincidence, and function of P-8.
3 Loop Flow
PR greater than 48%
2/4
Automatically unblocks low flow in one loop Rx trip
Describe the permissive, setpoint, coincidence, and function of P-9.
Turbine Trip - Rx Trip
PR greater than 50%
2/4
Unblocks Rx trip on turbine trip
Describe the permissive, setpoint, coincidence, and function of P-10.
Nuclear at Power
PR greater than 10%
2/4
1. Feeds P-7
2. Blocks SR HV
3. Permits block of IR Rx trip and rod stop
4. Permits block of PR High flux (low setpoint) trip
Describe the permissive, setpoint, coincidence, and function of P-11.
Pressure SI
Pressure less than 1970 psig
2/3
1. Permits block of PZR pressure and steam pressure SI signals
2. Allows steam line isolation on high pressure rate
Describe the permissive, setpoint, coincidence, and function of P-12.
Low-Low Tavg
Tavg less than 550F
2/4
Block steam dumps
Describe the permissive, setpoint, coincidence, and function of P-13.
Turbine at Power
Impulse pressure greater than 10%
1/2
Feeds P-7
Describe the permissive, setpoint, coincidence, and function of P-14.
SG High Level
Level greater than 78%
2/4 channels on 1 of 4 SGs
1. Trips Feedwater control valve
2. Trips Main Feedwater Pumps
3. Trips Main Turbine
4. Closes Feed Isolation valves
