ML20069L565
| ML20069L565 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 04/15/1983 |
| From: | Haisler R BELOIT CORP. |
| To: | Moore D, Murphy NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II), SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| REF-PT21-83 PT21-83, NUDOCS 8304280240 | |
| Download: ML20069L565 (5) | |
Text
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50-595 td !.ggsjgp maen Anna WW 535 M 608/365-4 91 W 60029 April 15,1983 N
f United States Nuclear Regulatory Commission g
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,A Suite 3100 p2 Atlanta, GA 30303 12 5 na~z Attention: Mr. Murphy p c M } k ji-)$ p W
_ South Carolina Electric & Gas q!
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P. O. Box 764 Columbia, SC 29218
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Manager of Quality Assurance y
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Subject:
Potential ~ Defect in a Westinghouse SA-1 4F(6 Generator Differential Relay, Shipped
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to-South Carolina Electric & Gas Virgil B. Summerstation Gentlemen :
Please be advised that Westinghouse has advised us of a potential defect in relays known as SA-1 relay. This potential defect can cause the relay to trip in a condition when it should not trip.
If this occurs, it will trip the generator circuit breaker, causing loss of the standby generator output, which is safety related.
Westinghouse advises that the problem is an SCR ccnufactured by ST. Semicon and were first purchased January 10, 1980. They also advise to check the unit to see if the units contain an SCR manufactured by ST Semicon, If it 'does, then notify yo'ur closest Westinghouse Sales Office per the attached Westinghouse letter dated 4/11/83.
Our history shows that one (1) relay is involved.
It is at the Virgil B.
-Summer Generating Station, South Carolica Electric & Gas.
South Carolina Electric & Gas Purchasa Order #Q311-777 to Colt Ind. FMED Colt Service Order Number 11-726170 Colt P.O. to' Louis Allis Beloit Power Systems Number 8441272-0 Beloit Power Systems Sales Order Number 586197 BPS Ship Date 6/24/82 Colt Ship Date 7/29/82 BPS Part Number 01703321-lE All other relays shown on the Westinghouse letter of 4/11/83 are located at Louis Allis Beloit Power Systems and Westinghouse is being notified that 611 the relays here contain the St Semicon SCR's.
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2-Please advise me when final disposition of this relay has been obtained.
If I can be of further assistance, please call or me.
Sincerely, Richar K. Haisler Manager of Qual!ty Assurance -
Louis Allis Beloit Power Systems RKH/bkw Attachment I
cc: Ken Rehard Colt (w/attacilment)
Dick Keyser Colt ("
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Harlan Leusink BPS
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Shef Massey BPS
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Walt Liermann, Sr. - BPS
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'815,398 3591 April 11, 1983 Beloit Power Systems 555 Lawton Avenue Beloit, Wi 53511 Attn:
Mr. Roger Churchill Subj: Class 1E SA-1 Relays Uninitiated Trip Output Potential
Dear Roger:
We have had reports from the field that ccmmercial relays have trip outputs when there have been no system conditions war provided put.
on - becoming conductive with no gate input) of a silicon ranting an out-ng rectifier in the trip output circuit.
happening in SA-1 relays, commercial or Class lE, but the SA-1 utiliThere h same SCR in a similar trip circuit.
zes the Q.A. and Engineering have been intestigating these reports.
have been tested. devices returned from the field and over 150 d Eighteen we have learned to date.The following comments anc conclusions are based on whatuse 1.
Certain SCR's can provide a random trip output.
2.
single manufacturer, ST Semicon.The phenomena appears to be e
rom a devices on January 10, 1980.
We first started to purchase these 3.
of ambient temperature, voltage and time.The tendency to pro story The higher any of these parameters, the more likely an ST Semicon SCR wi'.1 orovide a random trip.
4.
out" devices that may exhibit this ter4dency.ST Semicon ha e ng
" Burning-in" consists of placing an SCR in an 80 degree C. ambient for 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> with 500VDC applied, anode to cathode.
without becoming conductivt Devices which go through this process are believed to be good devices.
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Mr. Roger Churchill 4/11/83 5._ Our investigation is continuing and we have not, at this time, decided on a corrective action.
Please review the SA-1 relays below. Any relays containing SCR's that were manufactured by Westinghouse (identified by a (W) logo and 2N1850 printed on the barrel) or SYNTRON (identified by a -E}K: logo and 184A614) are not
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believed'co be subject to this phenomena.
SCR's manufactured by ST Semicon (identified by a logo and CR127) are suspect. Aside from the " burn-in" of11 tem 4 above, we do not have any method of determining which particular ST Semicon'SCR's will exhibit-this tendency.
Serial No.
(W) G.O. Number & Item Customer Order Number 15256A.
RK43470-N1-9 01507' 5257A RK43470-N1-9 01507 5258A
'RK43470-N1-9 01507 5259A RK43470-N1-9 10507 5486 RK43330-N1-25 01401 7 5487.
RK43330-N1-25 01401./
7437 RK44202-N1-3 32476'}
7438 RK44202-N1-3 32476 7439 RK44202-N1-3 32476 7440 RK44202-N1-3 32476 r-7441 RK44202-N1-3 32476 7442 RK44202-N1-3 32476 32476) 7443 RK44?02-N1-3 32476 7444
- RK44202-N1-3 7455 RK44202-N1-3 33858 -
Since we have not completed our investigation and do not have a final solution at this time, we-would like to postpone making any revisions to SA-1 relays in-the field. The purpose for sending this letter is to alert
-you toothe situation and propose interim actions if you have SA-1 relays applied where the potential for a random trip, as-evidenced by the presence of_an ST Semicon SCR in the relay, should be removed.
Our proposed interim action is to replace the existing-SCR with a " Burned-in" SCR.
This may'be accomplished by returning the relay to us as an RMR.
We will' replace the SCR with a " burned-in" device, recalibrate, re-inspect and test.in Q.A. and provide new replacement. Engineering has indicated taht the SCR may be replaced without affecting the calibration of~the relay.
If field replacement is decided upon, we recommend that the " Adjustments and Maintenance" and Electrical CheckpointsY sections of I.L. 41-348-11
" Type SA-1 Generator Differential Relay for Class lE applications" be followed.
If field replacement is accomplished, we request that a memo so stating be sent to me so our Class.1E records for each serialized relay can be kept up-to-date.
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Mr. Roger Churchill '4/11/83 Since've have not decided upon a final corrective action, the above may turn out to be an interim action to reduce the probability of a random trip output being produced by a SA-1 relay.
It may be necessary at a later date to recall. relays modified as proposed above, to further modify them in line with our final corrective action.
This would only be necessary if we believe that " burn-in" is not as effective as our-final corrective action.
We do not have' application information or knowledge necessary to perform an evaluation to determine if the potential for random trips from Class lE SA-1 relays with ST.Semicon SCR's as described above, could. create a substantial safety hazard in your application of these relays.
If you have the required application information or knowledge, you should determine if this potential is creating a substantial safety hazard in the Class lE application of these relays.
If,you determine that a safety hazard exists you should take appropriate reporting action as required by NRC Regulation.10CFR Part.21, " Reporting.of Defects'and Non-Compliance".
One of the purposes of this lettar is to initiate a chain of reporting that wi11' continue until the person (s) who-is able to make this determination is informed of the potential for random trip output.
If relays are to be returned or " burned-in" SCR's are to be supplied; arrangements should be made.
Sincerely,
& Sw Brad Cannon Asst. Sales Engineer ik
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