Section 3.1 Reactivity Control Systems Flashcards
- LCO 3.1.3.1 Movable Control Assemblies*
- *
When is LCO 3.1.3.1 Movable Control Assemblies Applicable?
MODES 1 and 2
All S/D and Control Banks shall be OPERABLE AND within ± 12 steps of their group step counter demand position.
- LCO 3.1.1.1 SDM*
- *
What is the definition of SDM?
Amount of reactivity by which the Rx is subcritical or would be subcritical assuming all full-length RCCA’s (S/D and Control) are fully inserted w/ highest reactivity RCCA stuck at top of core.
- LCO 3.1.1.1 SDM*
- *
What is the bases for the different regions of the SDM curve in the COLR?
Constant SDM Region (1.3 % ∆p)
Protect against uncontrolled C/D from SLB
Variable SDM Region
Protect against boron dilution accident
- LCO 3.1.1.1 SDM*
- *
When must SDM be verified prior to criticality?
MODE 2 w/ keff < 1
Within 4 hrs prior to criticality
Also performed prior to operations > 5% RTP after refueling.
LCO 3.1.1.3 MTC
What is the limit for negative MTC at core EOL?
-62.6 pcm / ˚F
It cannot be positve at 100% at EOL
Note:
No limit at BOL
- LCO 3.1.3.1 Movable Control Assemblies*
- *
What are your ≤ 1 hour action(s) if > 1 rod is trippable but inoperable due to something other than being immovable due to friction / mechanical interference?
- LCO 3.1.3.1 Movable Control Assemblies*
- Action D*
- *
Power Operation may continue provided that:
- Remainder of Rods in group aligned to within ± 12 steps on group counter while maintaining rod sequence and insertion limits of COLR [1 hr]
- Thermal power restricted per LCO 3.1.3.6 Control Rod Insertion Limits [1 hr]
- LCO 3.1.3.2 Position Indication Systems - Operating*
- *
When is LCO 3.1.3.2 Position Indication Systems - Operating Applicable?
MODES 1-2
- LCO 3.1.3.1 Movable Control Assemblies*
- *
What are your ≤ 1 hour action(s) if 1 rod is trippable but inoperable due to something other than being immovable due to friction / mechanical interference OR > ± 12 steps from it’s group counter?
- LCO 3.1.3.1 Movable Control Assemblies*
- Action B*
- *
Power Operation may continue provided:
- Rod restored to OPERABLE status [1 hr]
OR
- Rod declared INOPERABLE [1 hr]
- Remainder of Rods in group aligned to within ± 12 steps on group counter while maintaining rod sequence and insertion limits of COLR [1 hr]
- Thermal power restricted per LCO 3.1.3.6 Control Rod Insertion Limits [1 hr]
OR
- Rod declared inoperable [1 hr]
- Verify SDM [1 hr]
- LCO 3.1.3.6 Control Rod Insertion Limits*
- *
When is LCO 3.1.3.6 Control Rod Insertion Limits Applicable?
MODES 1-2
- LCO 3.1.3 Movable Control Assemblies*
- *
What are the bases for LCO 3.1.3 Movable Control Assembly Section Specifications?
Ensures that acceptable power distribution limits are maintained.
Ensures that the minimum SDM is maintained
Ensures potential effects of rod misalignment on associated accident analysis are limited
LCO 3.1.1.4 Minimum Temperature for Criticality
What are your ≤ 1 hour action(s) if any loop’s Tavg < 561 ˚F?
- LCO 3.1.1.4 Minimum Temperature for Criticality*
- Action A*
- *
- Restore Tavg ≥ 561 ˚F [15 mins]
OR
- Be in MODE 3 [15 mins]
- LCO 3.1.3.4 Rod Drop Time*
- *
What are the entry conditions for LCO 3.1.3.4 Rod Drop Time?
Tavg ≥ 561 ˚F
All RCPs running
Rod drop time should be ≤ 2.8 secs
- LCO 3.1.1.1 SDM*
- *
When is LCO 3.1.1.1 SDM Applicable?
MODES 1 - 5
LCO 3.1.1.4 Minimum Temperature for Criticality
When is LCO 3.1.1.4 Minimum Temperature for Criticality Applicable?
MODES 1-2
- LCO 3.1.1.1 SDM*
- *
While in MODES 3-5, SDM must be evaluted once per 24 hrs. Which factors must be taken into consideration?
RCS Boron Concentration
Xenon Concentration
RCCA position
Tavg
Fuel Burnup
LCO 3.1.1.4 Minimum Temperature for Criticality
What is the bases for the Minimum Temperature of Criticality?
MTC is within its analyzed temperature range
The trip instrumentation is within its normal operating range
The PZR is capable of being in an OPERABLE status with a steam bubble
The reactor vessel is above its minimum RTNDT
- LCO 3.1.3.5 S/D Rod Insertion Limit*
- *
When is LCO 3.1.3.5 Shutdown Rod Insertion Limit Applicable?
MODES 1-2
- LCO 3.1.1.1 SDM*
- *
What are your ≤ 1 hour action(s) if SDM is not within the limits specified in the COLR?
- LCO 3.1.1.1 SDM*
- Action A*
- *
Initiate Boration to restore SDM [15 min]
- LCO 3.1.1.1 SDM*
- *
What must SDM be greater than in MODES 1 -2?
> 1.3 % ∆p
SDM: The instantaneous amount of reactivity by which the reactor is subcritical or would be subcritical from its present condition assuming:
- All RCCAs fully inserted
- Highest reactivity RCCA fully withdrawn
LCO 3.1.1.3 MTC
When is LCO 3.1.1.3 MTC Applicable?
BOL (+MTC) Limit
MODES 1-2
EOL (-MTC) Limit
MODES 1-3
- LCO 3.1.3.5 S/D Rod Insertion Limit*
- *
What are your ≤ 1 hour action(s) if 1 S/D rod is NOT fully withdrawn?
- LCO 3.1.3.5 Shutdown Rod Insertion Limit*
- Action A*
- *
- Fully withdraw S/D Rod [1 hr]
OR
- Declare rod inoperable [1 hr]
AND
- Apply LCO 3.1.3.1 Movable Control Assemblies [1 hr]
- LCO 3.1.3.1 Movable Control Assemblies*
- *
What are your ≤ 1 hour action(s) if ≥ 1 rods inoperable due to being immovable due to friction / mechanical interference or is known to be untrippable?
- LCO 3.1.3.1 Movable Control Assemblies*
- Action A*
- *
- Determine SDM [1 hr]
- LCO 3.1.3.4 Rod Drop Time*
- *
When is LCO 3.1.3.4 Rod Drop Time Applicable?
MODES 1-2
