ML20084D635
| ML20084D635 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 04/23/1984 |
| From: | Tramm T COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 8502N, NUDOCS 8405010421 | |
| Download: ML20084D635 (2) | |
Text
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Commonwealth Edison
) one F fst Nitional Plaza. Chicago. Ilhnois
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~ 7 Address Reply to. Post Office Box 767 Q' Chicago, lihnois 60690 April 23, 1984 Mr. Harold R. Denton, Director Of fice of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Generating Station Units 1 and 2 Braidwood Generating Station Units 1 and 2 Diesel Generator Load Testing NRC Docket Nos. 50-454, 50-455, 50-456 and 50-457
Dear Mr. Denton:
The purpose of this letter is to clarify our intentions regarding the load testing of emergency diesel genertors at Byron and Braidwood stations.
A corresponding clarification of the Byron Safety Evaluation Report is needed to prevent future misunderstandings regarding our commitments.
The response to FSAR questions 40.93 and 40.115 delineate Commonwealth Edison's commitments regarding load testing of the emergency diesel generators.
Periodic load tests will be conducted to demonstrate diesel operability as prescribed by the plant Technical Specifications.
The same test will also be performed following diesel maintenance activities to verify operability.
If extended'no-load operation of a diesel is necessary, that diesel will be loaded to at least 25% of rated capacity for one hour following every eight hours of continuous no-load opration.
This should prevent the buildup of deposits in the cylinders and exhaust piping.
The Byron SER correctly documents these commitments and indicates that we have committed to load testing under other circumstances as well.
On page 9-47, item (3) indicates that if diesel troubleshooting activities continue for an extended period of time (three to four hours or more) the engine would be load tested for an' hour at a minimum of 25%
of rated capacity.
From discussions with NRC staff we understand that some diesel manufacturers recommend load testing after repeated starts during troubleshooting.
Cooper-Bessemer, the manufacturer of our diesels, has advised us that they do not impose any such limitation.
They believe that load testing after eight hours of no-load operation is adequate to protect their four-cycle diesels, regardless of the number of starts.
Accordingly, the operating and maintenance procedures at Byron and Braidwood contain no requirements for the load testing troubleshooting chich is contemplated in item (3) on page 9-47 of the Byron SER.
8405010421 840423 PDR ADOCK 05000454 E
PDR i o
y 1
H.
R. Denton April 23, 1984 It is requested that the NRC make an appropriate supplement to the SER.
Please contact this office if further discussions are needed.
Commonwealth Edison and Cooper-Bessemer personnel can be made available on short notice.
One signed original and fifteen copies of this letter are provided for NRC review.
Very truly yours, h#h T. R.
Tramm Nuclear Licensing Administrator 1m 8502N