ML19318A992
| ML19318A992 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/17/1980 |
| From: | Crouse R TOLEDO EDISON CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8006240494 | |
| Download: ML19318A992 (3) | |
Text
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TOLEDO
%mm EDISON A,cemo p CmouSE Vw.e Omsa:ent Docket No. 50-346 jl7lg 3,g License No. NPF-3 Serial No. 622 June '7,1980 Director of Nuclear Reactor Regulation Attention:
Mr. Robert W. Reid, Chief Operating Reactors Branch No. 4 Division of Operating Reactors United States Nuclear Regulatory Commission Washington, D.C.
20555
Dear Mr. Reid:
This letter is in reply to your letter of 5/5/80 on loss of off-site power. Davis-Besse Unit #1 has had two incidents of total loss and three inciderts of partial loss.
These incidents were previoush' brought to your attention via Licensee Event Reports as outlined below.
Type of Loss Date LER Total 11/29/77 NP-33-77-98 Partial 12/6-7/77 NP-33-77-106 Partial 2/13/79 NP-33-79-29 Partial 2/28/79 NP-32-79-01 Total 10/15/79
!?-32-79-11 Below are answers to the specific questions in your May 5, 1980 inquiry:
A.
For losses of off-site power where less than off-site pow vas lost:
1.
How many circuits to the off-site natwork are normally available, and how many were lost during the event?
['002 See LER's referenced above.
See also FSAT. figure 8-Ja.
S
/[6 THE TCLEDO EDISON COMPANY EDISON PLAZA 300 MADISCN AVENUE TOLECO. CHIO 43S52 8M0 Vf
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- Docket No. 50-346; Lic:nsa No. NPF-3 Serial No. 622; June 17,1980 2.
What was the cause of the event?
See LEP'1 lieted above.
3.
Why did the other lines not fail when some did fail?
See LER's referenced above.
4.
Was any voltage increase or decrease experienced just prior to or during the outage? If so, please give details, voltages reached, effects, etc.
See LER's referenced above.
5.
Was any frequency decay experienced just prior to or during the outage? If so, please give details, lowest frequency reached, decay rate, effects on equipment operation, etc.
The Toledo Edison system does not experience fluctuations in frequency.
Specifically, for the LER's referenced above there was no frequency decay.
6.
How long was power unavailable from the circuit?
Reference LER's listed above.
7.
Date of event.
Reference LER's listed above.
B.
For losses of all off-site power:
1.
How long was power off? How long for partial recovery? Please give details.
Reference LER's listed above.
2.
If turbine trip occurred, how soon after did loss of off-site power occur?
Reference LER's listed above.
3.
If power was recovered promptly (ten minutes or less), was it due to automatic or manual actions?
i Reference LER's listed above.
4.
Was any voltage increase or decrease experienced just prior to or during the outage? If so, please give details, voltages reached effects, etc.
Reference LER's listed above.
l
. - - Docket No. 50-346; Licensa No. NPF-3 S2rici No. 622; Jun317,1980 5.
Was any frequency decay experieaced just prior to or during the outage? If so, please give details, lowest frequency reached, decay rate, effects on equipment operation, etc.
Reference item A.S. above and LER's referenced above.
6.
Date of event.
Reference LER's listed above.
Yours very truly, 4
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