ML19257D646
| ML19257D646 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 12/27/1979 |
| From: | Moody D VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-79-25, NUDOCS 8002050243 | |
| Download: ML19257D646 (2) | |
Text
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C VER310NT YAN KEE NUCLEAR POWER CORPORATION SEVENTY SEVEN GROVE STR EET gf RUTLAND, YER.510 NT O!,701 l47 REPLY TO:
ENGINEERING OFFICE TURNP!KE RO An
' ESTDORO. M ASS ACHUSETTS 01581 9
TELEPHONE 617-366-9014 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 Attention:
Office of Inspection and Enforcement Mr. Boyce H. Grier, Director
Reference:
(1) License No. DPR-28 (Docker No. 50-271)
(2) USNRC Letter to VYNPC dated November 2, 1979; IE Bulletin 79-25
Dear Sir:
Subject:
NRC IE Bulletin No. 79-25; Westinghouse BFD Relays As required in Reference (2), we are providing the following information.
Vermont Yankee has conducted an investigation of the application of the subject relays in safety related systems.
It has been determined that BFD relays with coil style 503C428G21 are utilized in each of the emergency diesel generator control circuits.
BFD relays with unverified style numbers are also used in miscellaneous safety circuits.
1.
The BFD relays in the diesel generator control circuits are used for indication, trips and alarms, and generator starting. All these relays are normally de-energized except for the following three relays:
- Control power failure alarm relay. This relay remains energized at all times as long as control power is available.
- Engine low speed relay and engine nor=al speed relay.
These two relays are continuously energized only during diesel generator operation.
Diesel generator relays which perform an active function during starting and operation of the diesels are verified operable conthly by the monthly start and test operation of the diesels. Other relays only operate for abnormal conditions. Ver=ont Yankee will make inspection of these relays part of the annual diesel inspection procedure. Vertont Yankee does not have any record of past failures of these relays and does not see the need to establish a program to replace them.
1872 077 k 800005 0 24 3
United States Nuclear Regulatory Comaission December 2 7, 1979 Attn: Office of Inspection and Enforcement Page 2 2.
BFD relays are used in motor control circuits for valves, pumps and f ans which are. part of the following systems:
High Pressure Coolant Injection System Reactor Core Isolation Cooling System Residual Heat Removal System Main Steam Line Drain Isolation System Reactor Water Cleanup System The BFD relays in the above systems are used to provide seal-in contacts in valve opening and closing circuits, to provide contacts for valve position or motor status indicating lights, and to provide contacts for various interlocks.
The style numbers of these relays cannot be verified during plant operation. These relays will be physically checked during the forthcoming plant shutdown scheduled to begin on or about February 16, 1980, to de termine if they have style numbers listed in Reference (2).
If such relays are identified, and, if the identified relays have not been periodically tested as part of an existing surveillance program, Vermont Yankee will develop a su rveillance procedure to periodically verify operability of these relays.
We trust that you find this information satisfactory; however, should you desire additional information, please contact us.
Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION M
E. Moody Manager of Operations GTs/jgh 1872 078