ML20210H204
| ML20210H204 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 03/20/1986 |
| From: | Watson R CAROLINA POWER & LIGHT CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| CON-NRC-431, REF-PT21-86, REF-PT21-86-142-000 215, HO-860249(O), HO-860249-(), HO-860249-(O), NBI-051, NBI-51, PT21-86-142, PT21-86-142-000, NUDOCS 8604030006 | |
| Download: ML20210H204 (4) | |
Text
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CP&L Carolina Power & Light Company 1
HARRIS NUCLEAR PROJECT P.O. Box 165 c:
New Hill, N.C.
27562
~
MAR 2 01999 r;
p File Number:
SHF/10-13510 C
~~
Letter Number: HO-860249 (0)
NRC-431 r0 Dr. J. Nelson Crace United States Nuclear Regulatory Commission Region II 101 Marietta Street, Northwest (Suite 2900)
Atlanta, Georgia 30323 CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT 1986 - 900,000 KW - Unit 1 WESTINGHOUSE SAFETY CRADE CORE EXIT THERMOCOUPLES, ITEM 215
Dear Dr.' Grace:
Attached is our fourth interim report on the subject item, which was deemed reportable per the provisions of 10CFR50.55(e) and 10CFR, Part 21 on May 28, 1985.
CP&L is pursuing this matter, and it is currently projected that corrective action and submission of the final report will be accomplished by June 30, 1986.
Thank you for your consideration in this matter.
Yours ve:y truly,
$O R. A. Watson Vice President Harris Nuclear Project MW:ctm l
Attachment cc: Messrs. C. Maxwell (NRC-SHNPP)
(
J. M. Taylor (NRC)
)
l 8604030006 8 400 PDR ADOCK O DR S
NBI-OSI
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ag CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR P0'wsR PLANT UNIT 1
-FOURTH INTERIM REPORT WESTINGHOUSE SAFETY GRADE CORE EXIT THERMOCOUPLES ITEM 215-MARCH 18, 1986
. REPORTABLE UNDER 10CFR50.55(e) AND 10CFR, PART 21 i
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t IBMD-WKKF04-OS4
SUBJECT:
Shearon Harris Nuclear Power Plant - Unit No. I 10CFR50.55(e) and 10CFR21 Reportable Deficiency.
Testing of various components of the Safety Grade Core Exit T/C System indicates that the thermocouple signal will be maintained although some errors could be experienced during HELB. This potential error could exceed the allowance for certain systems using the thermocouple system.
ITEM:
Safety Grade Core Exit Thermocouples SUPPLIED BY:
Westinghouse NATURE OF DEFICIENCY:
As part of qualification testing done by Westinghouse during the WCAP 8587 Program, some errors were experienced in the thermocouple signal. These errors are postulated to be caused by a combination of moisture ingression and thermal expansion in the thermocouples, connectors, potting adapters, splices, and the reference junction box.
The thermocouple signal is used in three areas at Shearon Harris: Reactor Coolant System (RCS) subcooling margin, the detection of Inadequate Core
. t-Cooling (ICC), and temperature compensation of the Westinghouse Reactor Vessel Level Indication System (RVLIS).
DATE PROBLEM OCCURRED:
CP&L was notified May 10, 1985.
DATE PROBLEM REPORTED:
On May 28, 1985, CP&L (N. J. Chiangi) notified the NRC (Mr. A. Hardin) that the item was reportable under the provisions of 10CFR50.55(e) and 10CFR, Part 21.
SCOPE OF PROBLEM:
These potential errors affect the RCS subcooling margin calculation, the Inadequate Core Cooling detection, and the RVLIS temperature compensation.
Note that the effect on RVLIS was only recently made known to CP&L via a revised Westinghouse submittal to the NRC (NS-NRC-86-3099 dated February 20, 1986)
IBMD-WKKF04-0S4
SAFETY IMPLICATION:
Errors to the RCS subcooling and Inadequate Core Cooling systems have been shown to be within redefined accuracy requirements by Westinghouse..The thermocouple system is not, however, of sufficient accuracy as a RVLIS input to assure that appropriate operator actions are taken.
REASON DLFICIENCY IS
. REPORTABLE:
This is reportable as a design error since, as presently designed, the error in the thermocouple input to RVLIS is greater than that assumed in the present analysis.
CORRECTIVE ACTION:
With respect to RCS subcooling and Inadequate Core Cooling, CP&L is awaiting revised setpoint and accuracy information from Westinghouse so that design documents and procedures can be revised as necessary.
Regarding the RVLIS temperature compensation,
~
Westinghouse is preparing a design package and material to change from thermocouple compensation to loop RTD compensation.
FINAL REPORT: The final report on this item is pending completion of the corrective actions described above.
It is currently projected that the final report will be issued by June 30, 1986.
IBMD-WKKF04-OS4