ML13308B527
| ML13308B527 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/14/1976 |
| From: | Head J SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| IEC-76-02, IEC-76-2, NUDOCS 8103110127 | |
| Download: ML13308B527 (1) | |
Text
Southern California Edison Company P. 0. BOXBoo 2244 WALNUT GROVE AVENUE J.
T.
HEAD, JR.
ROSEMEAD, CALIFORNIA 91770 TELEPHONE
-ICE PPESl~eN 213-572-1472 October,14, 1976 U. S. Nuclear Regulatory Commission Region V Office of Inspection and Enforcement Walnut Creek Plaza, Suite 202 1990 North California Boulevard Walnut Creek, California 94596 Docket No. 50-206 Attention: R. H. Engelken, Director
Dear Sir:
IE Circular No. 76-02 Relay Failures - Westinghouse BF (ac) and BFD (dc) Relays Reference is made to your correspondence of August 18, 1976 forwarding the subject circular.
San Onofre Unit 1 utilizes 53 Westinghouse BF and BFD relays in plant tripping circuits. A study was made to determine the function and operating parameters of these relays. Additionally, electrical schemes and test/calibration procedures were examined to determine if the operability of these relays was verified through normal surveillance testing, other routine testing or normal operation of the plant.
The study revealed 46 of the 53 relays are operationally tested at a frequency not exceeding six months. The remaining seven relays are tested at refueling inter vals. However, these seven relays are required to operate each time the plant is shut down and/or started up.
Based on the above, it is our conclusion that these relays are operationally tested at sufficient intervals to assure continuing reliability and no additional testing is required.
Sincerely, cc: Director, Office of Inspection and Enforcement Division of Reactor Inspection Program, Washington, D. C.
I