ML20215N349
| ML20215N349 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/31/1986 |
| From: | Bailey J GEORGIA POWER CO. |
| To: | Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| RTR-REGGD-01.075, RTR-REGGD-1.075 0822V, 822V, GN-1143, NUDOCS 8611050270 | |
| Download: ML20215N349 (2) | |
Text
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- Georgis Pbwer Company -
- Post Offica Box 282 Waynesborn Georgi 2 30830
~ Telephone 404 554-9961
~ 404 7244114 Southern Company Services, Inc.
Post Office Box 2625 Birmingham, Alabama 35202 Telephone 205 870-6011 gp g
October 31,11986 Director of Nuclear Reactor Regulation File: X7BC35 Attention:
Mr. B. J. Youngblood Log:
GN-1143 PWR Project l Directorate #4 Division of PWR Licensing A U. S. Nuclear Regulatory Commission Washington, D.C.
20555 REF:
(1) BAILEY (GPC) TO DENTON (NRC), GN-997, 7/15/86 (2) YOUNGBLOOD (NRC) TO. FOSTER-(GPC), 11/26/85' NRC DOCKET NUMBERS 50-424 AND 50-425 CONSTRUCTION PERMIT NUMBERS CPPR-108 AND CPPR-109 V0GTLE ELECTRIC GENERATING PIANT - UNITS 1 AND 2 SER OPEN ITEM 14b: SAFETY PARAMETER DISPLAY SYSTEM (SPDS)
Dear Mr. Denton:
Reference 1 provided a response to your staff's request, reference 2, concerning isolation devices used in the Plant Vogtle SPDS. On July 23, 1986 your staff contacted GPC by telephone requesting additional testing of the isolation devices with respect to maximum credible fault current and voltage.
As discussed with your staff, the SPDS derives its inputs via the Emergency Response Facility (ERF) computer from three sources:
(1) The NSSS analog signals via the 7300 system' cabinets; (2) The BOP digital inputs which utilize the Reliance Electric Company Isomate digital isolation system; and (3) The NSSS digital inputs via the plant safety monitoring system (PSMS) data link, described in FSAR Appendix 4A, and the process and effluent monitoring system (PERMS) data link, described in FSAR subsection 11.5.2.
As noted in reference 1 the isolation of the NSSS analog signals is addressed in WCAP-8892A. The additional testing requested by your staff on the BOP digital isolation devices has been completed and is discussed below.
N 8611050270 861031 PJR ADOCK 05000424
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Director of Nuclear Reactor' Regulation File: X7BC35 October 31, 1986 Log:
GN-1143 Page 2 The test was conducted by Corporate Consulting and Development Company Ltd., a subcontractor of the isolator. supplier, United Controls Inc. The. isolator
' board was tested to Plant Vogtle's maximum credible fault of 1050 amperes and a sustained overcurrent of 70 amperes at 125VDC for this application. The test results show that'when the fault current or sustained overcurrent was applied to the non-class 1E circuit (output) until such time as the current was interrupted by the self fusing characteristic of the components on the board, no effect was propagated to the class 1E circuits (input). Applicable documentation related to the test including the supplier's test report is available in project files.
It is our conclusion that the test has confirmed that the Reliance Isomate Digital Isolator board meets the requirements as an isolation device per Regulatory Guide 1.75, IEEE 279 and IEEE 384.
l The NSSS digital safety signals fed _into the ERF computer via the PSMS or PERMS data links has' been completed. _ ' Results of these tests as they relate to your questions, reference 2, will be provided to your. aff within one week.
If your staff requires any additional information, please do not hesitate to contact me.-
S ce rely,
.l.
J. A. Bailey Project Licensing Manager JAB /sm xc:
R. E. Conway NRC Regicnal Administrator NRC Resident Inspector R. A. Thomas J. E. Joiner, Esquire D. Feig:
l B. W. Churchill, Esquire R. W. )!cMaaus M. A. Miller (2)
.L. T. Gucwa
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B. Jones, Esquire Vogtle Project File l
G. Bockhold, Jr.
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0822V I
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