TS 3.3.1 Reactor Protective System (RPS) Instrumentation - Operating Flashcards
3.3.1 RPS Instrumentation - Operating
LCO 3.3.1 ___ RPS trip and bypass removal channels for each Function in Table 3.3.1-1 shall be OPERABLE
Four
APPLICABILITY: According to Table 3.3.1-1
The RPS is segmented into four interconnected modules: Measurement channels Bistable trip units RPS Logic Reactor Trip circuit breakers
LCO 3.3.1 addresses ___ and ___. It also addresses ___
Measurement channels
Bistable trip units
ALSO automatic bypass removal feature for those trips with operating bypass
For LCO 3.3.1, the CPC’s provide outputs to drive display indications (___ ___ ___) and provide ___ and ___ pretrip and trip signals (from TS Bases 3.3.1)
DNBR Margin, LPD margin, calibrated neutron flux power levels
Provide DNBR-Low and LPD-High pretrip and trip signals
For LCO 3.3.1, regarding Bistable Trip Units…
“A channel is inoperable if its actual set point is ___ with respect to its Allowable Value”
Non-conservative
Each RPS set point is chosen to be consistent with the functions of the respective trip. The basis for each trip set point falls into 1 of 3 general categories:
1 - To ensure that the SLs are not exceeded during AOOs
2 - To assist the ESFAS during accidents
3 - To prevent material damage to major plant components (equipment protective)
The RPS-VOPT can provide protection against core damage during the following events:
1 - Uncontrolled CEA Withdrawal from subcritical and Low Power (AOO)
2 - CEA Ejection (Accident)
In Modes 3,4, or 5, with RTCB’s open or the CEAs not capable of withdrawal, the Log Power Level - High trip DOES or DOES NOT have to be Operable?
DOES NOT have to be Operable
- Indication and alarm functions required to indicate a boron dilution event are addressed in LCO 3.3.12 BDAS
The PZR Pressure - High trip provides protection for the high RCS Pressure SL. With PZR Safeties and MSSV’s, it provides protection against over pressurization of the RCPB during the following events:
1 - Loss of Condenser Vacuum
2 - CEA withdrawal from low power conditions
3 - CVCS Malfunction (AOO)
4 - Main FW System Pipe Break (Accident)
Per LCO 3.3.1 every Function has an Applicability of Modes 1 and 2 EXCEPT for ___
Log Power Level - High
- Applicable in Mode 2 ONLY
What is the NOTE for LCO 3.3.1?
Separate Condition entry is allowed for each RPS function
LCO 3.3.1 Condition A -
One or more Functions with one automatic RPS trip channel inoperable.
What are the Required Actions and Completion Times?
A.1 - Place channel in bypass or trip (1 Hour) AND
A.2 - Restore channel to OPERABLE status (Prior to entering Mode 2 following next Mode 5 entry(
LCO 3.3.1 Condition B -
One of more Functions with 2 automatic RPS trip channels inoperable.
Required Actions and Completion Times?
B.1 - Place 1 channel in bypass and the other in trip (1 Hour)
LCO 3.3.1 Condition C -
One or more Functions with 1 automatic bypass removal channel inoperable.
Required Actions and Completion Times?
C.1 - Disable channel bypass (1 Hour) OR
C.2.1 - Place affected auto trip channel in bypass or trip (1 Hour) AND
C2.2 - Restore bypass removal channel and associated auto trip channel to OPERABLE status (Prior to entering Mode 2 following next Mode 5 entry)
LCO 3.3.1 Condition D -
One or more Functions with 2 auto bypass removal channels inoperable.
Required Actions and Completion Times?
D.1 - Disable bypass channels (1 Hour) OR
D.2 - Place 1 affected auto trip channel in bypass and place the other in trip (1 Hour)
LCO 3.3.1 Condition E -
Required Action and associated Completion Time not met.
Required Actions and Completion Times?
E.1 - Be in Mode 3 (6 Hours)
The general relationship among PVNGS trip set point terms is as follows:
The calculated limiting set point is determined within the plant specific set point analysis and is based on the ___ and the ___
Analytical Limit and the Total Loop Uncertainty
The Log Power Level - High Trip operating bypass is auto removed when log power decreases below ___
1E-4% NRTP
When indicated Log power channel is failed HIGH (>1E-4%), the auto Hi-Log power trip bypass removal feature in that channel CAN or CANNOT function?
Cannot Function
- Both auto DNBR-LPD and Hi-Log Power bypass removal features are affected by a failed Log power channel and should therefore be considered INOPERABLE
The SG Level-Low RPS trip set point ensures that there will be sufficient water inventory in the SG at the time of the trip to provide margin of at least ___ minutes before AF is required to prevent degraded core cooling.
10 Minutes
The SG Level-High RPS trip set point is set low enough to ensure a reactor trip occurs before the level reaches the ___
Steam dryers
A CPC IS or IS NOT considered inoperable if CEAC inputs to the CPC are inoperable?
IS NOT considered inoperable
For LCO 3.3.1, Each CPC channel contains 6 processor modules. Failure of which module makes a CPC channel inoperable per LCO 3.3.1?
ONLY CPC Processor Module failure. Aux CPC Processor Module failures do NOT make the CPC channel inoperable.
- CEAC 1/2 and CPP 1/2 area addressed in LCO 3.3.3
Compliance with LCO 3.3.1 Condition C.1 is met by placing the ___ and ___ for the Hi-Log power and DNBR/LPD bypasses respectively.
CR switches in “off” and “normal”
Most trips are not required to be OPERABLE in Modes 3,4 and 5. Exceptions to this are:
- Log Power Level - Protects Boron dilution and CEA withdrawal events
- SG Pressure-Low - Protects MSLB in Mode 3
