ML20092D971

Part 21 Rept Re Thermal Nonrepeatability & Other Calibr Errors in Barton Lot 1 Transmitters.Initially Reported on 840615.Transmitter Defects Identified & Expected Error Deviations Calculated.Utils Notified

ML20092D971
Person / Time
Site:	Salem, Sequoyah, North Anna, Diablo Canyon, Farley, Cook, 05000000
Issue date:	06/15/1984
From:	Rahe E WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:	Deyoung R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
References
REF-PT21-84-277-000 NS-EPR-2931, PT21-84-277, PT21-84-277-000, NUDOCS 8406220230
Download: ML20092D971 (4)

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[ ]s Westinghouse Water Reactor Box 355 PittsburghPa11syNania 15230 Electric Corporation Divisions NS-EPR-2931 June 15, 1984 Mr. R. C. DeYoung, Director i

Division of Inspection and Enforcement U.S. Nuclear Regulatory Commission Phillips Building 7920 Norfolk Avenue Bethesda, Maryland ,

20014

Dear Mr. DeYoung:

This is to confirm the telephone conversation of June 15, 1984, between Messrs. C. Draughon and D. Rawlins of Westinghouse and Mr. G. Lanik of the NRC. In that conversation, Westinghouse notified the NRC of a reportable item associated with the Barton Lot 1 transmitters supplied by Westinghouse to several NSSS customers. This item was reported under 10CFR 21 for three operating plants (Farley 1, D. C. Cook 2, and Sequoyah 1) as discussed below.

Westinghouse has advised these utilities of this issue.

In addition to these plants which have installed Lot 1 transmitters that do not meet the required accuracy, Westinghouse has shipped a number of other Lot 1 transmitters that could result in a similar condition if they were installed in an operating plant. Our information currently indicates that these devices are no longer installed in the plants to which Westinghouse shipped them. The affected transmitters as well as those installed in operating plants are listed in Table 1.

On October 13, 1983, in letter NS-EPR-2837, Westinghouse reported the issue of

" thermal non-repeatability" as it affected Westinghouse customers of Barton transmitters from the manufacturing Lots 2 through 7. As noted, Barton discovered excessive errors at both abnormal and accident temperature conditions and determined two separate causes. Barton's calibration technique for temperature compensation was found to result in previously undefined errors at both abnormal and accident temperatures. Barton also discovered that an electrical leakage path thru the wiper arm and shaft of the zero and span calibration potentiometers to the instrument case creates significant errors at high temperatures. Transmitters procured by Westinghouse from Barton Lots 1, 2, 4, 5, and 7 were potentially affected. In the October 13, 1983 letter, Westinghouse committed to supply the results of the ongoing evaluation of the Lot 1 transmitters to the NRC as necessary.

S PDR Ab'OCK84062 050002750230 840615 S PDR 0146G/RBM/6-84 gg 4 i ~

Westinghouse has recently received information o's Barton Lot 1 transmitters and has evaluated the thermal non-repeatability issue and other calibration errors and has found that for some plants there is insufficient margin in all function setpoints to absorb the additional errors identified. The additional calibration errors determined on Lot I were due to special temperature compensation techniques employed by Barton only on Lot 1 Transmitters. The Westinghouse evaluation has concluded that these techniques caused the error for initiating trip functions to exceed the tolerance specified if the transmitter internal temperature is in the range of 200-250 F.

Based on a review of the calibration data from Barton on each Lot 1 transmitter supplied to Westinghouse, we have calculated the expected error deviations and discussed the effect of any additional deviations on the functions performed by these transmitters with the affected utilities. The containment high pressure trip provides a backup to the safety injection, reactor trip and auxiliary feedwater pump initiation functions for which steam generator narrow range level is the primary trip so the utility may want to demonstrate the adequacy of this trip rather than change the steam generator 10-10 level setpoint.

If you have any questions or would like to discuss this issue further, please contact Clarence Dratghon of my staff at 412-374-5761.

Very truly yours, E. P. Rahe, Manager 4 Nuclear Safety Department CGD/ KEG

-0146G/RBM/6 _

r Table 1 Plant Function Serial Number A. Operating plants with installed affected Lot 1 transmitters.

D. C. Cook 2 Pressurizer Pressure 763-316 Pressurizer Pressure 763-317 SG NR LYL 764-193 SG NR LVL 764-194 SG NR LVL 764-195 SG NR LVL 764-196 SG NR.LYL 764-200 SG NR LVL 764-342 SG NR LYL 764-197 SG NR LVL 764-198 Farley 1 SG NR LVL 764-128 SG NR LVL 764-129 SG NR LVL 764-130 SG NR LVL 764-132 SG NR LYL 764-137 SG NR LVL 764-162 SG NR LVL 764-163 Sequoyah 1 SG NR LVL 764-221 SG NR LYL 764-223 SG NR LVL 764-225 SG NR LYL 764-226 SG NR LVL 764-228 B. Plants to whom affected Lot 1 transmitters were shipped by Westinghouse, but which our best information indicates that the devices are no longer installed.

Salem 2 SG NR LVL 764-151 SG NR LVL 764-152 SG NR LVL 764-153 SG NR LVL 764-155 SG NR LVL 764-156 SG NR LYL 764-159 Diablo Canyon 1 SG NR LVL 764-138 SG NR LYL 764-139 SG NR LVL 764-140 SG NR LVL 764-143 SG NR LVL 764-145 SG NR LYL 764-146 SG NR LVL 764-147 SG NR LVL 764-149 0146G/RBM/6-84

m Table 1 Plant Function Serial Number Diablo Canyon 2 3G NR LVL 764-119 SG NR LVL 764-123 SG NR LYL 764-124 SG NR LVL 764-122 SG NR LVL 764-126 North Anna 1 Pressurizer Pressure 763-137 North Anna 2 Pressurizer Pressure 763-311 Pressurizer Pressure 763-312 Pressurizer Pressure 763-313 0146G/RBM/6-84