ML20062K801
| ML20062K801 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 08/11/1982 |
| From: | Tramm T COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 4733N, NUDOCS 8208180011 | |
| Download: ML20062K801 (2) | |
Text
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^N Commonwealth Edison r
/ Oro First National Pirzt Chic 1go. Illinois 7 h Address Reply to: Post Office Box 767 (j Chicago, Illinois 60690 Augus t 11, 1982 Mr. Harold R.
Denton, Director Of fice of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 Residual Heat Removal System NRC Docke t Nos. 50-454, 50-455, 50-456, and 50-457 Re ference (a):
April 14, 1982 letter from T. R. Tramm to H. R.
Den to n.
Dear Mr. Denton:
This is to provide revised information regarding a Byron /Braidwood design feature which will aid the operator during switchover from ECCS injection to recirculation following a LOC A.
Review of this information should close Confirmatory Issue 27 of the Byron SER.
Attachment A to this letter contains the details of a circuit change which will provide control room indication of the safety injection S-signal status.
This will aid the operator during ECCS switchover and in other aspects of recovery from En accident.
Because of its broader usefulness, this circuit will be utilized at Byron and Braidwood in place of the one described in reference (a).
Summary information regarding this change will be incorpo-rated into the FSAR at the next amendment.
Please address further questions regarding this matter to this of fice.
One signed original and fif teen copies of this letter and the attachment are providad for your review.
Very truly yours,
/
AfbW T. R.
Tramm Nuclear Licensing Administrator 1m l
Attachment
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8208180011 820811 DT PDR ADOCK 05000454 4733N E
t-SARGENT & LUND'Y E N GlN E E N S
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August 5, 1982 ATTAC!! MENT A During safety injection when the water level in the RWST reaches a preset trip point, there is an automatic switchover from injection mode to recirculation mode.
Manual resetting of the safety injection signal will disable the automatic switchover.
The NRC's concern was that the operator would not be aware that the automatic switchover was disabled since no indication of the reset was provided.
The safety injection reset circuit will be revised to include an indicating light that will be " turned on" when a safety injection signal is present and " turned off" when the signal is reset.
The indicating light will also have a push-to-test feature that will allow the operator to verify that it has not burned out.
A typical schematic of the indicating light circuit is provided below:
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The K647 Relay is the Output Latch Relay for the Safety Injection Latch Relay K602 as shown.in the following sketch:
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R (SCPS)
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4 gco.2 T " K6474,q K602
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