ML20095E831

Proposed TS Bases 2.2.1,deleting Unnecessary Details Re Time Delay Requirements for Undervoltage & Underfrequency RCP Trip Setpoints

ML20095E831
Person / Time
Site:	Comanche Peak
Issue date:	12/15/1995
From:	TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:
Shared Package
ML20095E824	List: ML20095E820 ML20095E831
References
NUDOCS 9512180169
Download: ML20095E831 (3)

Text

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BASES EDE TECHNICAL SPECIFICATION SECTION 2.2.1 REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS UNDERVOLTAGE AND UNDERFREQUENCY - REACTOR COOLANT PUMP BUSSES e

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PDR 1

CPSES - TECHNICAL SPECIFICATIONS AMENDMENT-42 DETAILED DESCRIPTION Prefix Page Page 1 (as amended)

Group Deerintion B2

-8 2

Delete unnecessary details from Technical Specification Bases (2.2.1) regarding time delay requirements for the Undervoltage and Underfrequency Reactor Coolant Pump trip setpoints.

' Revision Technical Specification Bases 2.2.1 describes the undervoltage and underfrequency reactor coolant pump trip requrements. The specific statements regarding the response time for the RCP undervoltage (l.2 seconds) and the underfrequency (0.3 second) is deleted from the Technical Specification Bases 2.2.1. The statements regarding the "1.2" and "0.3" q

seconds were part of the Westinghouse Standard Technical Specifications (NRC letter to CPSES dated 8/14/87). The specific time intervals discussed in these statements are not explicitly used in the accident analyses of FSAR Chapter 15 or the Reactor Trip System instrumentation Response Times in TRM Table 1.1.1. The requirements for undervoltage and underfrequency response times exist and belong in Technical Requirements Manual Table 1.1.1.

Change Request Number TS 7

.1 Related SER 16 SSER : 22 SER/SSER 1mpact

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LIMITING SAFETY SYSTEM SETTINGS t

i RASES

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i Undervoltaae and Underfrecuency - Reactor Coolant P"=a Russes f

The Undervoltage and Underfrequency Reactor Coolant Pump Bus trips provide

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core protection against DN8 as a result of complete loss of forced coolant flow. The specified setpoints assure a Reactor trip signal is generated before the Low Flow Trip Setpoint is reached. Time delays are incorporated in iAe Underfrequency and Undervoltage trips to nrevent sourious Reactor trips fNa

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momentary electrical power transients.R:7 xd:rnit:::, th: 5:!:; t: nt n "th:t r: ^^ n n ;;; n : Tr :.4;t: t: rr ? th: ".r t:r tri; tr n i:n f:ll;u-f ; th; ;init. x x LH ; Of tr :r = = = =t:r erl =t ;

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t.;. hec;.h.11 nt :n nd 1.d c r:dr.

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'-'-+t it rr?:d 559 et rrf 0.? cr^-d J on decreas'ng power the Undervoltage and Underfrequency Reactor Coolant Pump Bus trips are automatically blocked by P-7 (a power level of approximately 105 of t

RATED THERMAL POWER with a turbine first stage chamber pressure at approxi-mately 10% of full power equivalent); and on increasing power, reinstated i

automatically by P-7.

Turbine Trio A Turbine trip initiates a Reactor trip. On decreasing power the Reactor trip from the Turbine trip is automatically blocked by P-9 (a power level of approximately 50% of RATED THERMAL POWER); and on increasing power, reinstated automatically by P-g.

Safety Iniection Innut from ESF If a Reactor trip has not already been generated by the Reactor Trip System 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 3.3-2.

d COMANCHE PEAK - UNITS 1 AND 2 B 2-7

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