ML20101P063
| ML20101P063 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 04/04/1996 |
| From: | Carns N WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| WM-96-0044, WM-96-44, NUDOCS 9604090258 | |
| Download: ML20101P063 (2) | |
Text
I W$LF CREEK NUCLEAR OPERATING CORPORATION Neil S. " Buzz" Carns Chairman, President and April 4, 1996 Chief Executwe Officer WM 96-0044 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station F1-137 Washington, D.
C.
20555
Subject:
Docket No. 50-482:
Response to Request for Review of Draft Information Notice Regarding Fires in Emergency Diesel Generator Exciters During Operation Following l
Undetected Fuse Blowing Gentlemen:
This letter provides Wolf Creek Nuclear Operatang Corporation's (WCNOC) comments on the draft Information Notice.
The draft Information Notice discusses events at the Wolf Creek Generating Station that involved fires in both trains of the Emergency Diesel Generator excitor potential transformers.
The first three comments involve phrasing suggestions.
The last two comments below reflect actions that have been taken or completed.
Comment Number 1:
Page 1 of 4,
last paragraph states that the progressive insulation breakdown was caused by sustained current well in excess of the winding ampacity (emphasis added).
Evaluation of the condition indicated the current was in excess of the winding ampacity, but not significantly so.
The use of the word "well" is not quantifiable and could be misinterpreted. WCNOC suggests deleting well.
Comment Number 2:
Page 2 of 4,
first full paragraph states the fuses had blown in each case as the result of manual engine shutdown.
Manual should be changed to mechanical to more appropriately reflect technical terminology.
Comment Number 3:
Page 2 of 4, last paragraph states the reason for the blown fuses at Wolf Creek revealed another apparent design deficiency.
The design functions were reviewed, and it was determined that no design deficiencies existed.
This was particularly true in the case of manual shutdown by mechanical means, i.e.,
use of the emergency stop lever.
The lever is provided by the manufacturer on all medium to large engines and is not unique to nuclear applications.
The lever is provided as a means to allow emergency stopping of the engine when all other means to secure the engine have proved unsuccessful and immediate shutdown is required because the overriding concern is to secure the engine.
WCNOC suggests rewording to state,
...ruvealed areas for design awareness."
9604090258 960404 PDR ADOCK 05000482 O
PDR P O Bon 411/ Burhngtort KS f4839 / Phone (316) 364-8831 I E An Ew opwturwty Ernptovar M 1 McM f 1
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- WM %-0044 Page 2 of 2 J
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i Comment Number 4:
Page 4 of 4, fiist paragraph states the fuse indication is I
being evaluated. The fuse indication has been installed.
Comment Number 5: 'Page 4 of 4, second paragraph states-that the licensee, in consultation with ' others, is evaluating the design.
A design change to 1
install volts-per-hertz protection has been evaluated and installed.
'I WCNOC appreciates the opportunity to review the draft Information Notice and I
provide these comments.
If you have any questions concerning this matter, please call me at (316) 364-8831, extension 4100, or Mr. Richard D.
Flannigan at extension 4500.
Very truly yours, l
j Neil S. Carns i
l NSC/jra 1
cc:
L.
J. Callan (NRC) l W. D. Johnson (NRC)
{
J.
F. Ringwald (NRC)
J. C. Stone (NRC)