ML18054B102

Provides Interpretation of Setpoints Specified in Tech Spec 3.1.8 to Allow +22 Psia for Pressure Instrument Inaccuracy & +/- 4.5 F for Temp Instrument Inaccuracy.Nrc Approval of 890922 Change to Tech Spec Will Obviate Interpretation

ML18054B102
Person / Time
Site:	Palisades
Issue date:	11/14/1989
From:	Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TAC-72889, NUDOCS 8911210082
Download: ML18054B102 (2)

Text

f.

consumers Power Kenneth W Berry Director POWERiNii Nuclear Licensing MICHlliAN'S PROliRESS General Offices: 1945 West Parnall Road, Jackson, Ml 49201 o (517) 788-1636 November 14, 1989 Nuclear Regulatory Connnission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR~20 - PALISADES PLANT -

TECHNICAL SPECIFICATION 3.1.8 - LETTER OF INTERPRETATION Technical Specification 3.1.8 specifies that when the PCS temperature is less than or equal to 300°F, two PORVs with a lift setting of less than or equal to 310 psia shall be operable; and, when the PCS temperature is greater than 300°F but less than 430°F, two PORVs with a lift setting of less than or equal to 575 psia will be operable.

Consumers Power Company interprets the 310 psia and 575 psia PORV maximum setpoints specified in Technical Specification 3.1.8 to allow +22 psia for pressure instrument inaccuracy. Consumers Power Company also interprets the 300°F and 430°F setpoints specified in Technical Specification 3.1.8 to allow

+/-4.5°F for temperature instrument inaccuracy. These tolerances are technically justifiable because the maximum allowable setpoints specified in the Technical Specifications are at least 32 psi lower than the 10 CFR 50 Appendix G curve, providing ample margin for instrument inaccuracies plus pressure overshoot (Ref. 1). In addition, the required 10 CFR 50 Appendix G pressure/temperature limits as displayed on Figures 3-1 and 3-2 of the Technical Specifications include an additional allowance of 30 psi for pressure measurement errors and 5°F for temperature measurement errors.

A proposed change to Technical Specification 3.1.8 that changed the maximum allowable PORV setpoints and addressed the consideration of_allowable setpoint tolerances was submitted September 22, 1989 (Tac No. 72889). NRC approval of that proposed change will obviate this Letter of Interpretation, thus, this letter of interpretation shall be terminated at that time. Meanwhile, Consumers Power Company will not consider it a reportable event if the PORV setpoints are found to deviate from the specified pressure (310 psia or 575 psia) or temperature* (300°F or 430°F) setpoints as long as the deviations are with in the allowable instrument inaccuracy ranges (+/-22 psia and +/-4.5°F).

rl=:91--1::::*1~C1!*i-c**-:*

. - * - * . - - .. - ,_,.,:;,. ___ ,_,_ *L 1--1---"--~

• =*o:::i** ,,..... *""1'.

• PDR ADOCK Ct50<J0255, /\oo f

p "PDC ~

OC1189-0011-NL02 A CMS ENERGY COMPANY

• _r J

.. -~

e **

Nµelear Regulatory Commission Palisages Nuclear Plant TS 3.1.8 - Ltr of Interpretation November 14, 1989

• 2 This letter supersedes Consumers Power Company letter dated July 12, 1989.

The earlier letter of interpretation for technical sp~cification addressed only the allowable variation of the pressure setpoint.

Kenneth W Berry Director, Nuclear Licensing CC Administrator, Region III, USNRC NRC Resident Inspector ~ Palisades Reference

1. Engineering Analysis E-PAL-89-015-01, LTOP Setpoint Margins.

OC1189-0011-NL02