RCS Flashcards
Purpose of RCS
Main- xfr heat from core to secondary
Sec- pressure boundary
- second fission product barrier - promote nat circ - moderate neutrons
RCS design bases
Ensure every penetration has 2 auto close cap- cnmt isolation
Leakage detection capabilities(rad mon, smp lvl, cfcu)- RCS integrity
Handle +/-10 %step, 5% ramp 100-15% pwr, 95% LR- reliable plant load chgs
Location PT-405
Loop 3 hot leg
Location PT-403
Loop 4 hot leg
Location PT-403A
Loop 4 hot leg
Location PT-405A
Loop 4 hot leg
WR RCS Press inputs
PT-403/ 405
- SCMM
- RVLIS
- SPDS
- PPC
- CR ind
WR RCS Press inputs
PT-403A/ 405A
- SPDS
- RHR intlk, (suct. vlvs won’t open if >390 psig)(8701/8702)
- Pzr PORV open signal if > 435 psig (if LTOP armed)
- CR ind
RCS flow xmtrs Lp 1 FT-414, 415, 416 Lp 2 FT-424, 425, 426 Lp 3 FT-434, 435, 436 Lp 4 FT-444, 445, 446
- SSPS (low flow Rx Trip, < 90% flow)
- CR ind
Delta T outputs
- indication
- RIL comp (PPC)
- OP(delta)T
- OT(delta)T
Tave outputs
- OP(delta)T
- OT(delta)T
- P-12 (low-low Tave permissive)
- FW iso
- PPC
- ind
- rod cntrl (auct hi)
- stm dmps (auct hi)
- Pzr lvl cntrl (auct hi)
Auctioneered delta T outputs
- delta T deviation alarm
- RIL calc (pwr input)
Auctioneered Tave outputs
- Tave deviation alarm
- Tave hi alarm
- Rod cntrl
- stm dmp cntrl
- Pzr lvl ref
- (if fails hi, thrown out if 10 deg deviation)
Precautions and limitations for RCS
- during dilutions maintain Pzr [B] and RCS [B] w/in 50 ppm
- max c/d 100 deg/ hr
- max h/u 60 deg/ hr
- maintain press / temp w/ in PTLR
- minimum temp criticality (>541 deg)
Unit differences
Rx vessel internals differences => unit 2 higher flow rate