05000361/LER-1982-090, Forwards LER 82-090/03L-0.Detailed Event Analysis Submitted

Forwards LER 82-090/03L-0.Detailed Event Analysis Submitted

ML20067A048
Person / Time
Site:	San Onofre
Issue date:	09/03/1982
From:	Ray H SOUTHERN CALIFORNIA EDISON CO.
To:	Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML20065B011	List: 05000361/LER-1982-090, Forwards LER 82-090/03L-0.Detailed Event Analysis Submitted 05000361/LER-1982-090-03, /03L-0:on 820807,turbine Isolation Valves Declared Inoperable Due to Inability to Place Turbine Overspeed Protection Sys in Exercise Mode.Caused by Intermittent Sticking of Hydraulic Dump Valve Position Switches
References
NUDOCS 8209140199
Download: ML20067A048 (2)

LER-1982-090, Forwards LER 82-090/03L-0.Detailed Event Analysis Submitted

Event date:
Report date:
3611982090R00 - NRC Website

text

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s8 Southern California Edison Company a-

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S AN ONOF RE NLCLEAR GE NER A TING S T A TION

/j p.O. 13 O M 126 SAN C L EME N T E, C A LIF OR NI A 92672 H. B. R A Y ictapso%e

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Septemoer 3, 1982 U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596-5368 Attention:

Mr. R. H. Engelken, Regional Administrator

Dear Sir:

Subject:

Docket No. 50-361 30-Day Report Licensee Event Report No.82-090 San Onofre Nuclear Generating Station, Unit 2 This submittal is in accordance with the reporting requirements of Section 6.9.1.13b of Appendix A to Facility Operating License NPF-10.

It describes a reportable condition involving Limiting Condition for Operation (LCO) 3.3.4 associated with the Turbine Overspeed Protection System (TOPS). A completed copy of LER 82-090 is enclosed.

While in Mode 2, at 2121 on August 7, 1982, the weekly TOPS valve testing in accordance with procedure S023-3-3.34 was in progress.

Due to inability to place the TOPS in the exercise mode for valve cycling tests in accordance with Technical Specification 4.3.4.2.a, the turbine isolation valves were declared inoperabic. As required by the associated Action Statement, the Main Steam Isolation Valves (MSIV's) and MSIV bypasses were verified shut, isolating the turbine from the steam supply.

The inability to place the TOPS in the exercise mode is attributable to problems associated with sticking of contacts on hydraulic dump valve position switches ZSL 8204-A and ZSL 8205-B.

After jumpers were placed across tMse switches the turbine isolation valves were successfully tested and declared operable at 0230 on August 8, 1982.

8209140199 820903 PDR ADOCK 05000361 S

PDR gf y 2A -317

f Mr. R. H. Engelken September 3, 1982 Further investigation revealed that the switch problem (contacts sticking) was intermittent since the valves have been tested successfully (without the jumpers) on two occasions following this event. A check of the surveillance testing history for the TOPS indicates that this was the first time that problems with the switches have occurred at this plant.

These switches are not part of the safe ty related trip function, and since the MSIV's and bypasses remained closed throughout the event, there was no impact on health and safety of plant personnel or the public.

If there are any questions regarding the above, please contact me.

Sincerely,

[

Enclosure:

LER 82-090 cc:

A. E. Chaf fee,(USNRC Resident inspector, San Onof re Unit 2)

U. S. Nuclear Regulatory Commission Office of inspection and Enforcement U. S. Nuclear Regulatory Commission Of fice of Management Information and Program Control Institute of Nuclear Power Operations 4