ML18053A552

Proposed Tech Specs Re Core Exit Thermocouples

ML18053A552
Person / Time
Site:	Palisades
Issue date:	09/02/1988
From:	CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18053A551	List: ML18053A550 ML18053A552
References
NUDOCS 8809070322
Download: ML18053A552 (5)

Text

• ATTACHMENT Consumers Power Company Palisades Plant Docket 50-255 PROPOSED PAGES TECHNICAL SPECIFICATIONS CHANGE REQUEST CORE EXIT THERMOCOUPLES I 880907 0 I ~DR ADS~ 880902 05000255 RNU 4 Pages OC0888-0088-NL04

3.17 INSTRUMENTATION AND CONTROL SYSTEMS (Contd)

If the bypass is not effected, the out-of-service channel (Power Removed) assumes a tripped condition (except high rate~of y~hange of power, high power level and high pressurizer pressure), which results in a one-out-of-three channel logic. If, in the 2 of 4 logic system of either the reactor protective system or the engineered safeguards system, one channel.is bypassed and a second channel manually placed in a tripped condition, the res~lting logic is 1 of 2. At rated power, the minimum operable high-power ,level channels is 3 in order to provide adequate flux tilt detection. If only 2 channels are operable, the reactor power level is reduced to 70% rated power which protects the reactor from possibly exceeding design peaking factors due to '

undetected flux tilts and from exceeding dropped rod peaking factors in the event that a turbine runback signal is required from the power range channels.

The engineered safeguards system provides a 2 of 4 logic on the signal used to actuate the equipment connected to each of the 2 emergency diesel generator units.

Two start-up channels are available any time reactivity changes are deliberately being introduced into the reactor and the neutron p~wer is not visible on the log-range nuclear instrumentation or above 10 % of rated power. This ensures that redundant start-up instrumentation is available to operators to monitor effects of reactivity changes when neutron power levels are only visible on the start-up channels. In the event only one start-up range channel is available and the neutron power level is sufficiently high that it is being .monitored by ~oth channels of log-range instrumentation, a startup can be performed in accordance with footnote (d) of ~able 3.17.4.

Sixteen (four per core quadrant) environmentally qualified core exit I thermocouples (cable and connectors) with readout from 0 to 2300°F are I provided for monitoring the potential approach to inadequate core I cooling. The core exit thermocouples are in integral part of the I incore detector assembly and are located at the top of .each incore I assembly to measure primary coolant core outlet temperatures. I References (1) Update FSAR, Sections 7.2.2 and7.2.7. I 3~77 Amendment. No. ~.

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Table 3~17.4 (Cont'd)

Minimum Minimum Permissible Operable Degree of Bypass No Functional Unit Channels Redundancy Conditions

8. Pressurizer Water 2 1 Not required in Level (LI-0102) Cold or Refuel-ing Shutdown

9. Pressurizer Code 1 per None Not Required Safety Relief Valves Valve below 325°F Position Indication (Acoustic Monitor or Temperature Indication)

10. Power Operated R~lief 1 per None Not required when Valves (Acoustic Valve PORV isolation valve Monitor or Temperature is closed and its Indication) indication system is operable

11. PORV Isolation Valves 1 per None Not required when Positipn Indication Valve reactor is depressurized and vented through a vent i:::l.3 sq.in.

12. Subcooling Margin 1 None Not required Monitor below 515°F

13. Auxiliary Feed Flow 1 per flow) None Not required Rate Indication Controh) below 325°F Valve

14. Auxiliary Feedwater 2 per stetW) 1 Not required Actuation System generator below 325°F Sensor Channels

15. Auxiliary Feedwater. 1 Not required Actuation System below 325°F Actuation Channels

16. Excore Detector None None

( )* Core Exit 4/core None Not required I Thermocouples Quadrant below 325°F I (1, m, n, o) I 3-Sla Amendment No. ~7.~S, 9~,

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• Table 3.17.4 (Cont'd)

(e) Auxiliary Feedwater System Actuation System Sensor Channels contain pump auto initiation circuitry. If two sensor channels for one steam generator are inoperable, one of the steam generator low level bistable modules in one of the inoperable channels must be in the tripped condition.

(f) With one Auxiliary Feedwater Actuation System Actuation Channel inoperable, in lieu of the requirement of 3.17.2, provide a second licensed operator in the control room within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. With both inoperable, in lieu of following the requirements of 3.17.2, start and maintain in operation the turbine driven auxiliary feed pump.

(g) Calculate the Quadrant Power Tilt using the excore readings at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when the excore detectors deviation alarms are inoperable.

(h) With two flow rate indicators inoperable for a given control valve, the control valve shall be considered inoperable and the requirements of 3.5.2(e) apply.

(1) The provisions of Specification 3.0.4 are not applicable. I (m) The environmentally qualified core exit thermocouples are I used in determining the minimum channels operable requirement. I (n) With the number of OPERABLE Core Exit Thermocouples less than four per I core quadrant but greater than or equal to two per core quadrant, I in lieu of the requirement of 3.17.2, either restore the inoperable I channel(s) to OPERABLE status within 7 days if repairs are feasible I without shutting down or prepare and submit a Special Report to the I Commission within 30 days following the event outlining the action I taken, the cause of the inoperability and the plans and schedule for I restoring the system to OPERABLE status. I (o) With the number of OPERABLE Core Exit Thermocouples less than two I per core quadrant, in lieu of the requirements of 3.17.2, either I restore two core exit thermocouples per core quadrant to OPERABLE I status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, or be in HOT SHUTDOWN or below within the I next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. I 3-8lb Amendment No. 9~. 9S, OC0888-0088-NL04

TABLE 4.1.3 Minimum Frequencies for Checks, Calibrations & Testing of Miscellaneous Instrumentation and Controls (Contd)

Channel DescriEtion 6

21 Core Exit Thermocouples( ) a.

b.

Function Check Calibrate Frequencl'.:

M (6) a.

b.

Surveillance Method Comparison of Channels Known voltage substituted for thermocouple

/.

I I

(6) Only.applicable to the environmentally qualified core exit thermocouples.

calibrated on a refueling cycle frequency.

These thermocouples will be I I

4-llb Amendment No.

OC0888-0088-NL04