ML20091A798

Proposed Tech Specs Allowing Installation of Interlock to Prevent Direct Reactor Trip Following Turbine Trip at or Below 50% Reactor Power

ML20091A798
Person / Time
Site:	Summer
Issue date:	05/23/1984
From:	SOUTH CAROLINA ELECTRIC & GAS CO.
To:
Shared Package
ML20091A787	List: ML20091A781 ML20091A798 ML20091A805
References
NUDOCS 8405300091
Download: ML20091A798 (5)

Text

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TABLE 2.2-1 (continued)

E REACTOR TRIP SYSTEM INSTRUNENTATION TRIP SETPOINTS c Total Functional Unit Allowance (TA) Z Trip Setpoint Allowable Value 5 S_

NA

18. Safety Injection Input NA NA NA NA from ESF  :; .

19. Reactor Trip System '

Interlocks ,

A. Intermediate Range NA .

NA NA 11 x IC 10 amps 16 x 10 11 amps Neutron Flux, P-6 B. Low Power Reactor Trips ,

Block, P-7

a. P-10 input 7.5 4.56 0 $10% of RTP 112.2% of RTP T 4.56 0 <10% turbine <12.2% of turbine-

" b. P-13 input 7.5 Tapulse pressure impuise pressure equivalent equivalent 4.56 C. Power Range Neutron 7.5 0 138% of RTP 140.2% of RTP Flux P-8 Low Setpoint Power 7.5 4.56 0 >10% of RTP 17.8% of RTP D.

Range Neutron Flux, P-10 Turbine Impulse Chamber 7.5 4.56 0 <10% turbine <12.2% turbine E. pressure equivalent Pressure, P-13 Tapulse pressure equivalent

q NA NA NA

20. Reactor Trip Breakers NA ,- NA u

NA

21. Automatic Actuation Logic NA ,NA , NA NA

~

8405300091 840523 RTP = RATED THERMAL POWER p DR ADOCK 05000395 PDR '

4 s0% ., RT P 6 52.."l% a, RTP Pm Ra c Nemou 7.5 9.ss o F.

Fw , P ci L_______ . _ __ - _ _ - -

'. LIMLTING SAFETY SYSTEM SETTINGS

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, BASES Steam /Feedwater Flow Mismatch and Low Steam Generator Water Level (Continued) level setpoint, as indicated by the narrow range instrument. These trip values include sufficie.J allowance in excess of normal operating values to preclude spurious trips but will initiate a reactor trip before the steam

. generators are dry. Therefore, the required capacity and starting time requirements of the auxiliary feedwater pumps are reduced and the resulting thermal transient on the Reactor Coolant System and steam generators is minimized. .

Undervoltage and Underfrequency - Reactor Coolant Pump Busses The Undervoltage and Underfrequency Reactor Coolant Pump Bus trips provide reactor core protection against DNB as a result of complete loss of forced coolant flow. The specified set points assure a reactor trip signal is generated before the low flow trip set point is reached. Time delays are incorporated in the underfrequency and undervoltage trips to prevent spurious reactor trips from momentary electrical power transients. For undervoltage, the delay is set so that the time required for a W 'al to reach the reactor trip breakers following the simultaneous trip of two or more reactor coolant pump bus circuit breakers shall not exceed 1.2 seconds. For underfrequency, the delay is set so that the time required for a signal to reach the reactor trip breakers after the underfrequency trip set point is reached shall not exceed 0.6 seconds. On

.(b' ',

decreasing power the Undervoltage and Underfrequency Reactor Coolant Pump Bus -

trips are -automatically blocked by P-7 (a power level:of approximately~10 per-cent.of RATED THERMAL POWER with a-turbine-impulse chamber pressure at - " -

approximately 10 percent of full power equivalent); and on increasing power, ,

reinstated automatically by P-7.

Turbine Trip ATurbineTripinitiatesareactortrip. On d::r::&g p: :r th: turbin:

trip ! -"t---tir-1?y 5!cchM by "-? (e p r 'e"el e# pp-e"-etely M pe cett-ef "'TE" T" P". . P^"2 wi th turbin: !--& ch tr et vpre..' :tely la pei;ei.; e7 full pe.es equiValei.tI, ;it. ;7. iiii;;;ir.;; p;.;;7, 7;ii.;t;t;d este.T.etically by P-7. 4 Safety Inject'. ion Input from ESF If a reactor trip has not already been generated by the reactor protective instrumentation, the ESF automatic actuation logic channels will initiate a reactor trip upon any. signal which initiates a safety injection. The ESF instrumentation channels which initiate a' safety injection signal are shown in

• Table 3.3-3.

On occas4smo eom, Tus as4eron rw mn rne ruums tm u.

I Automemc ALW B t oc.KED BY E-9 (A POWER LEVEL ta ss T uH og geV AL TO 50% o,. R ATED THERMAL POWER);3,o on ,uco 33,,o powen,

( BE W5 T ATE D AUTO M AT \C ALW BY SulHER'- UNIT 1 P ci .

B 2-7 l

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LIMITING SAFETY SYSTEM SETTINGS BASES Reactor Trip System Interlocks The Reactor Trip System Interlocks perform the following functions

' P-6 On increasing power P-6 allows the manual block of the Source Range reactor trip and de-energizing of the high voltage to the detectors.

On decreasing power, Source Range level trips are automatically '

reactivated and high voitage restored.

P-7 On increasing power P-7 automatically enables reactor trips on low -

flow in more than one primary coolant loop, more than one. reactor 4

coolant pump breaker open, reactor coolant pump bus undervoltage and underfrequency, turb b: tH;;, pressurizer low pressure and pressurizer high level. On dccreasing power the above listed trips are automati-cally blocked. -

P-8 On increasing power P-8 automatically enables reactor trips on low flow in one or more primary coolant loops, and one or more reactor coolant pump breakers open. On decreasing power the P-8 automatically blocks the above listed trips. -

P-10 On increasing power P-10 allows the manual block of the Intermediate

' Range reactor trip and the low setpoint Power Range reactor trip; and de-energizes and automatically the Source blockspower.

Range high voltage the Source Range On decrtasing po reactar trip'wer the Inte mediate Range reactor trip and the low setpoint Power Range reactor trip are automatically reactivated. Provides input to P-7.

P-13 Provides input to P-7.

P-9 Or4 INCRE. AS I N O POWG g

P Ci auronATic Au Y E N AS t. E 5 REACTOR TRIP ow Tuneiss inie. On oscasAsmo powca P cg BLOcv5 suyoor cou,y RfACTOR TRgP oN TURBnt4E TMP i

1 SUPMER - UNIT 1 B 2-8 A )

TABLE 3.3-1 (Continued) 9 REACTOR TRIP SYSTEM INSTRUMENTATION e

c MINIMUM E TOTAL NO. CHANNELS CHANNELS APPLICABLE FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERABLE MODES ACTION

]

19. Reactor Trip System Interlocks A. Intermediate Range

• Neutron Flux, P-6 2 1 2 2, 7 B. Low Power Reactor Trips Block, P-7 P-10 Input 4 2 3 1 7 P-13 Input 2 1 2 1 7 C. Power Range Neutron Flux, P-8 4 2 3 1 7 R

• D. Power Range Neutron Flux, P-10 -

4 2 3 1, 2 7 T.

u E. Turbine First Stage Pressure, P-13 2 1 2 1 7

20. eactor Trip Breakers 2 1 2 1, 2 8 2 1 2 3*, 4*, 5* 9

21. Automatic Trip Logic 2 1 2 1, 2 8 2 1 2 3*, 4*, 5* 9 t'

o' F. Powsa Raraos NEWRON Y 1 3  !

Fuw , P-9

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..-l E TABLE 4.3-1 (Continued) .

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REACTOR TRIP SYSTEM INSTRLMENTATION SURVEILLANCE REQUIREMENTS s

c TRIP 3

ANALOG ACTUATING MODES FOR CHANNEL DEVICE WHICH

" ACTUATION SURVEILLANCE CHANNEL CHANNEL OPERATIONAL OPERATIONAL FUNCTIONAL UNIT CHECK CALIBRATION TEST TEST LOGIC TEST IS REQUIRED D. Low Setpoint Power Range Neutron Flux, P-10 N.A. R(4) M (8) N.A. N.A. 1, 2 E. _ Turbine Impulse Chamber Pressure, P-13 N.A. R ,

M (8) N.A. N.A. 1

20. Reactor Trip Breaker N.A. N.A. N.A. M (7, 11) N.A.

1, 2, 3*, 4*, 5*

21. Automatic Trip Logic N.A. N.A. N.A. N.A. M (7) 1, 2, 3*, 4*, 5" Y

t

y, t... Powen buss N.A R(O Ml8) N.A. N.A. I i

Neorgs F ,P-9 4

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