ML19322E948
| ML19322E948 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 03/27/1980 |
| From: | UNION ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML19322E943 | List: |
| References | |
| IEC-80-01, IEC-80-1, NUDOCS 8004040368 | |
| Download: ML19322E948 (1) | |
Text
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.{N 10CFR50.55(e) FINAL REPORT sl GENERAL ELECTRIC PROTECTIVE RELAYS CALLAWAY PLANT UNIT 1
1.0 INTRODUCTION
In compliance with 10CFR50.55(e) this final report is submitted covering potentially defective induction disc relays f
' identified in General Electric Service Advisory 721-162.2 dated March 1, 1978.
This problem is described in NRC IE Circular 80-01 dated January 17, 1980.
Our discovery of defective relays of this type at Callaway was initially reported to the NRC Resident inspector on February 29, 1980.
2.0 DESCRIPTION
OF DEFICIENCY The NRC IE Circular 80-01 " Service Advice for General LElectric Induction Disc Relay" dated January 17, 1980, indicated that General Electric induction disc type relays have been found with a higher than normal pick-up voltage caused by petroleum jelly lubricant which under high temperature conditions can migrate to the backstop.
At room temperature the lubricant becomes adhesive and causes pickup voltage to be higher than setpoint values.
We have checked the relays installed at Callaway Plant against the code letters of the relays listed in IE Circular No. 80-01.
On February 28, four relays having the listed identification code letters were found in applications which could have adversely affected safe operation of the plant.
These relays were Type IAV with Date Codes of 17BN, 17J1, and 17KM.
3.0-ANALYSIS OF SAFETY IMPLICATIONS The four. Type IAV relays listed in Paragraph 2.0 were installed as 4-kV Class IE bus offsite feeder undervoltage relays which permit tripping of the offsite feeder breaker when the offsite supply is in an undervoltage condition.
The emergency diesel associated with the respective 4-kV Class IE bus is started by other undervoltage relays in a two-out-of-four logic circuit, but the emergency diesel breaker cannot close until the offsite feeder breaker has tripped.
4.0 CORRECTIVE ACTION TAKEN Arrangements have been made to have General Electric Company come to Callaw ay to modify or replace all deficient relays, regardless of_their use in Class IE or Non-class IE circuits.
8004040 t
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