ML20207L256
| ML20207L256 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 06/30/1986 |
| From: | Watson R CAROLINA POWER & LIGHT CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| CON-NRC-460, REF-PT21-86, REF-PT21-86-277-000 215, HO-860313-(O), PT21-86-277, PT21-86-277-000, NUDOCS 8607300245 | |
| Download: ML20207L256 (4) | |
Text
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P Cp&L Carolina Power & Light Company ETE 1.14tylM E Kir72t'PumMpf. Ll1r Mai.YNT57 VEX 'img HARRIS NUCLEAR PROJECT C-P.O. Box 165 I-New Hill, N.C.
27562 ra JUN 3 01986 File Number:
SHF/10-13510 Letter Number: H0-860313 (0)
'i Dr. J. Nelson Grace United States Nuclear Regulatory Commissi~n o
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 GRADE CORE EXIT THERMOCOUPLES, ITEM 215
Dear Dr. Grace:
Attached is a final report on the subject item, which was deemed reportable per the provisions of 10CFR50.55(e) and 10CFR, Part 21 on May 28, 1985. With this report, Carolina Power & Light Company considers this matter closed.
If you have any questions concerning this matter, please do not hesitate to contact me.
Yours very truly, R. A. Watson Vice President Harris Nuclear Project MW:crm Attachment cc: Messrs. G. Maxwell (NRC-SHNPP)
J. M. Taylor (NRC) 8607300245 860630 DR
,,JCK 05000400 PDR fG 3.J NBI-OS1 M1
t CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1-FINAL REPORT WESTINGHOUSE SAFETY GRADE CORE EXIT THERMOCOUPLES ITEM 215 REPORTABLE UNDER 10CFR50.55(e) AND 10CFR, PART 21 IBMD-WKKF04-OS4/ Item 215
e.
v.
SUBJECT:
Shearon Farris Nuclear Power Plant - Unit No. 1 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 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
.l NRC (Mr. A. Hardin) that the item was reportable i
under the provisions of 10CFR50.55(e) and 10CFR, Part 1
21.
l 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 made known to CP6L via a revised Westinghouse submittal to the NRC i
(NS-NRC-86-3099 dated February 20, 1986) l l
l IBMD-WKKF04-OS4/ Item 215 L
o t
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 DEFICIENCY 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 has revised the required setpoints consistent with the current Westinghouse Owner's Group recommendations. Regarding the RVLIS temperature compensation, Westinghouse has prepared and submitted to CP&L a design package and material to change from thermocouple compensation to loop RTD compensation. This design change is essentially complete, with only a minor installation interference to be corrected by July 15, 1986.
IBMD-WKKF04-OS4/ Item 215