ML19210D845
| ML19210D845 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 11/02/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Burstein S WISCONSIN ELECTRIC POWER CO. |
| References | |
| NUDOCS 7911280128 | |
| Download: ML19210D845 (11) | |
Text
02^<dA a}
NOV2 5 79 Docket No. 50-266 Docket No. 50-301 Wisconsin Electric Power Company ATTN:
Mr. Sol Burstein Executive Vice President Power Plants 231 West Michigat Milwaukee, WI a3201 Gentlemen:
Encloseo is IE Bulletin No. 79-25 which requires action by with regard to your power reactor facilities with an operating license or a construction permit.
Should you have questions regarding this Bulletin or the actions required of you, please contact this office.
Sincerely, James G. Keppler Director
Enclosures:
1.
List of IE Bulletins Issued in the Last Six Months cc w/ enc 1:
Mr. G. A. Reed, Plant Manager Central Files Directar, NRR/DPM Direct or, NRR/ DOR C. M. Trammell, ORB /NRR
'Ji35
?95 PDR Local PDR NSIC TIC Sandra A. Bast, Lakeshore Citizens for Safe Energy RIII RIII Heishan/ge K#ppler 11/2/79 3931280 /lbb
UNITED STATES LSINS No.:
6820 NUCLEAR REGULATORY COMMISSION Accession No.-
0FFICE OF INSPECTION AND ENFORCEMENT 7908220139 WASHINGTON, D. C.
20555 November 2, 1979 IE Bulletin No. 79-25 FAILURES OF WESTINGHOUSE BFD RELAYS IN SAFETY-RELATED SYSTEMS Description of Circumstances:
While conducting response time tests on Westinghouse BFD relays at the H. B.
Robinson facility, two relays were found to be stuck in the energized position with the coil de-energized.
The twenty relays being tested were installed spares and provided no safety-related or operational function.
The subject relay is identified as a Westinghouse Electric Corporation type BFD, style 5069A95G03, coil style 1259C71G19.
Upon discovery of the two stuck relays in the test pro-gram, the licensee conducted response tests on similar relays installed in the Reactor Protection System.
During this additional testing a reactor trip relay was found to be stuck in the energized position.
Detailed investigation of the problem by the licensee's staff indicated that the armature was sticking to the a mature stop post.
This condition is apparently created when heat generated by n;rmally energized coils causes a softening and resultant flow of epoxy adhesive used to attach the magnetic antistick disc to the top of the armature stop post.
Wher sufficient adhesive flows to the top of the armature stop, the armature becomes bonded to the stop post, resulting in the relay sticking in the energized position.
The epoxy adhesive had also discolored to a dark brown as opposed to clear in new relays.
After reviewing this problem, Westinghouse issued a service letter dated December 6, 1978.
A copy of this letter is enclosed for your information and appropriate use. Westinghouse recommended replacing affected relays with a relay identified as NBFD, style 5072A49, coil style 1271C50G01, 125/130 Volt DC 10 percent.
During installation and testing of the new NBFD relays identified by Westinghouse, H. B. Robinson determined i'at some of the new style relays exhibited marginal or unsatisfactory armature overtravel.
An investigation of the problem by Westinghouse indicated that the insufficient overtravel was limited 'n eight and twelve pole models of the NBFD relays.
Westinghouse issued a Technical Bulletin NSD-TB-79-05 to Licensees.
A copy of this Technical Bulletin is also enclosed for your information and use. Westinghouse recommended a testing method for identifying relays with insufficient over travel and also recommended replace-ment of relays with insufficient overtravel.
Action to be Taken by Licensees:
For all power reactor facilities with an operating license or construction permit:
1.
Determine whether or not the used or planned for use in sa a.
Type BFD, style 46E7352 DUPLICATE DOCUMENP4 3 5 ? 9 6 b.
Type BFD, style 5069A35, c.
Type BFD, style 5072A49, Entire documedt previously entered into system und r:
[
ANO No. of pages:
_