ML20078A641
| ML20078A641 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 09/08/1983 |
| From: | Tramm T COMMONWEALTH EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, 10CFRE-50.55E, 7270N, 82-11, 82-12, NUDOCS 8309230355 | |
| Download: ML20078A641 (2) | |
Text
'
- j v'
[N Commonwealth Edison
[
l ) on) First N:tiorni Pipa Chictgo, Ittinois Addrtss R; ply to: Post Office Box 767 v
Chicago, Illinois 60690 September 8, 1983 Mr. James G. Keppler, Regional Administrator U.S.-Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137
Subject:
Byron Generating Station Units 1 and 2 Braidwood Generating Station Units 1 and 2 Barton Instrument Accuracy NRC Docket Nos. 50-454, 50-455, 50-456, and 50-457 References (a):
January 28, 1983, letter from T. R. Tramm to J. G. Keppler.
(b):
March 28, 1983 letter from T. R. Tramm to J. G. Keppler.
(c):
June 1, 1983, letter from T. R. Tramm to J. G. Keppler.
l
Dear Mr. Keppler:
1 References (a), (b), and (c) provided interim reports on a l
deficiency reportable pursuant to 10 CFR 50.55(e) regarding the accuracy l
of Barton electronic instrument transmitters being installed at Byron and l
Braidwood stations.
This letter provides a fourth interim report.
For NRC tracking purposes this deficiency is numbered 82-11 for Byron and l'
82-12 for Braidwood.
i As described in the previous interim reports on this deficiency, a design change involving the addition of an insulating washer into the j
l transmitter eliminates the majority of the instrument inaccuracy at acci-1 dent environment temperatures (3250F).
However, an accuracy problem still exists when the transmitter is exposed to abnormal environment i
temperatures (1300F).
I Barton has discovered that this remaining accuracy problem was caused by an incorrect manufacturing methodology used during the j
temperature compensation process.
The corrective action is a revised i
temperature compensation procedure.
The effect on transmitters compensated with the incorrect methodology is a possible increase in the temperature coefficient at 1300F and 3250F.
Ohho!oOkl4 PDR
\\
%2J7
J. G. Keppler 2-September 8, 1983 A final report on this deficiency is expected to be available in 60 days.
This report will include a list of transmitters that require the addition of an insulating washer and a list of transmitters that are affected by the improper temperature compensation.
Corrective actions being considered to eliminate the temperature compensation problem are transmitter recalibration, instrument setpoint adjustment, or evaluation of the transmitter inaccuracy for its specific application.
The final report will also include the corrective action for each transmitter affected by the temperature compensation problem.
Please address questions regarding this matter to this office.
Very truly yours, Tokf T. R. Tramm Nuclear Licensing Administrator 1m cc:
Director of Inspection and Enforcement 7270N
'I r
r.
e
,w---
--v,,- -. --=,
,-n.
- - -, _.