ML18153A191

LER 97-011-00:on 971030,determined That Periodic Test Procedures for Testing Reactor Trip Bypass Breakers Did Not Test Manual Undervoltage Trip.Caused by mis-interpretation of Term in-service. Procedures Revised

ML18153A191
Person / Time
Site:	Surry
Issue date:	11/26/1997
From:	Christian D VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML18153A190	List: ML18153A189 ML18153A191
References
LER-97-011, LER-97-11, NUDOCS 9712020116
Download: ML18153A191 (4)

Text

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB NO. 3150~104 (4-95) EXPIRES 4/30/98 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS.

., REPORTED LESSONS LEARNED ARE INCORPORATED INTO THE

-,,,, .-.* .. LICENSEE EVENT .REP.ORT (LER) ' . ***t LICENSING PROCCSS AND FED.*BACK TO INDUSTRY. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION ~ND RECORDS MANAGEMENT BRANCH (r-6 F33).

U.S NUCLEAR REGULATORY COMMISSION. WASHINGTON. DC

{See reverse for required number of digits/characters for each block) 20555-0001. AND TO THE PAPERWORK REDUCTION PROJECT (315M104). OFFICE OF MANAGEMENT AND BUDGET.

WASHINGTON. DC 20503.

FACILITY NAME (1) DOCKET NUMBER (2) PAGE (3)

SURRY POWER STATION , Unit 1 05000 - 280 1 OF 4 TITLE (4)

Improper Bypass Breaker Testinq Due to Inadequate Definition of In Service EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED 8)

SEQUENTIAL REVISION FACILITY NAME DOCUMENT NUMBER MONTH DAY YEAR YEAR MONTH DAY YEAR NUMBER NUMBER Surry Unit 2 05000-281 FACILITY NAME DOCUMENT NUMBER 10 30 97 97 -- 0 l l -- 00 11 26 97 05000-OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §. (Check one or more) (11)

MODE (9) N 20.2201(b) 20.2203{a){2)(v) X 50.73(a){2)(i) 50.73{a){2){viii)

POWER 20.2203(a)(1) 20.2203{a){3){i) 50. 73(a){2){ii) 50.73{a){2){x)

LEVEL (10) 100 °" 20.2203(a){2){i) 20.2203(a){3){ii) 50. 73(a){2){iii) 73.71 20.2203(a){2){ii) 20.2203{a){4) 50.73(a){2)(iv) OTHER 20.2203(a)(2){iii) 50.36{c){1) 50.73{a){2){v) Specify in Abstract below 20.2203(a)(2)(iv) 50.36{c){2) 50. 73(a){2){vii) or in NRC Form 366A LICENSEE CONTACT FOR THIS LER 12 NAME D. A. Christian, Station Manager COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT/131 1 ( ; ; ; ~ N ; ; ; : ; R ~ ; ; e Area Code)

CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE I

TO NPRDS TO NPRDS SUPPLEMENTAL REPORT EXPECTED (14) EXPECTED MONTH DAY YEAR I YES (If yes, complete EXPECTED SUBMISSION DATE).

IN I NO SUBMISSION DATE ABSTRACT {Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On October 30, 1997, with Unit 1 at 100% power and Unit 2 reactor critical with low power testing in progress, it was determined that the periodic test (PT) procedures for testing the reactor trip bypass breakers did not test the manual undervoltage trip prior to placing the breaker in service. Testing of the undervoltage trip had previously been conducted with the reactor trip bypass breakers racked into the connect position. Therefore, the breakers were actually in service at the time of the testing. The event was caused by a mis-interpretation of the term "in-service" and how it applied to the bypass breakers. The TS requirements were not properly incorporated into PT procedurF <, when they were revised. The PT procedures have been corrected and the bypass breakers have been satisfactorily tested.

No conditions adverse to safety resulted from this event and the health and safety of the public were not affected because testing of the reactor trip bypass breakers took place immediately after closing the bypass breakers and before the reactor trip breakers were open for testing. This event is being reported pursuant to 10 CFR 50.73(a)(2)(i)(B), any operation or condition prohibited by the plant's Technical Specifications.

9712020116 971126 PDR ADOCK 05000280 S PDR

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION, FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (3)

SURRY POWER STATION, Unit 1 YEAR I SEQUENTIAL NUMBER I REVISION NUMBER 05000 - 280 97 --011-- 00 20F 4 TEXT (If more space is required. use additional copies of NRC Form 366A) (17)

1.0 DESCRIPTION

OF THE EVENT

. Following the 1983 Salem Anticipated Transient Without Scram (ATWS) Event, Generic Letter (GL) 83-28, Generic Actions for Licensees and Staff in Response to the ATWS Events at Salem, Unit 1, was issued. Item 4.3 of this letter, Reactor Trip System Reliability, became the subject of GL 85-09, Technical Specifications (TS) for GL 83-28, Item 4.3 for Westinghour'3 Plants, and concluded that TS changes should be processed.

TS Amendment 117 dated February 17, 1988, for Surry Power Station Units 1 and 2, was issued by the NRG requiring surveillance testing of the reactor trip bypass breakers [EIIS-AA,BKR]. The TSs for bypass breaker surveillance testing were revised again by Amendment 137, dated February 5, 1990, for Surry Units 1 and 2, to reflect the current testing conditions. The current TSs specify that a test of the reactor trip bypass breakers be conducted once per month by tripping the remote manual undervoltage coil [EIIS-AA,CL]

prior to placing the breaker in service.

The reactor trip bypass breakers, Westinghouse Type DB-50, were maintained in the connect position during power operation. Periodic test (PT) procedures for performing the channel functional test on the bypass breaker specified that the breaker be closed and then tripped open from the test panel to verify operability. During the testing of the bypass breaker, Operations entered a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> clock as soon as the bypass breaker was closed, in accordance with TS Table 3.7-1, Reactor Trip Breaker Instrument Operability Conditions.

On October 30, 1997, with Unit 1 at 100% power and Unit 2 reactor critical with low power physics testing in progress, it was determined that testing of the bypass breaker may not be in verbatim compliance with TSs in that the breakers were actually connected and in service at the time of the testing. Therefore, operability was not being verified prior to placing the bypass breaker in service.

This report is being made pursuant to 10 CFR 50.73(a)(2)(i)(B), any operation or condition prohibited by the plant's Technical Specifications.

NRC FORM 366A (4-95)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

. TEXT CONTINUATION . ~~-~~~,u.--=*========.=====4 FACILITY NAME (1) DOCKET LER-NUMBER /6) PAGE (3)

SURRY POWER STATION, Unit 1 YEAR I s~~~:;~AL I ~~~!'i~

05000 - 280 97 --011-- 00 30F4 TEXT (If more space is required. use additional copies of NRC Form 366A) (17) 2.0 SAFETY CONSEQUENCES AND IMPLICATIONS No conditions adverse to safety resulted from this event and the health and safety of the

. public were not affected. The reactor trip bypass breakers were determined to be operable immediately upon closure by verifying that tripping the undervoltage coil would trip the bypass breakers. The bypass breakers were tested prior to opening the reactor trip breakers for testing. In addition, when the bypass breakers were closed, a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> clock was entered for an inoperable reactor trip crannel.

Prior to and subsequent to this event, testing of the reactor trip bypass breakers demonstrated that the breakers tripped on demand with no failures.

3.0 CAUSE The event was caused by a mis-interpretation of the term " in-service" and how it applied to the bypass breakers. The surveillance test procedures for the reactor trip breakers were revised in 1985 to test the bypass breakers by racking the bypass breaker into the connect position, closing the breaker, and then opening the bypass breaker by pushing the trip pushbutton on the test panel. On February 17, 1988, TS Amendment 117 was approved that required bypass breaker testing prior to placing the breaker in service. No changes were made to the surveillance procedures that modified the sequence of testing the bypass breakers. The reactor trip bypass breaker was understood to be in service when the reactor trip breaker for the opposite train was opened.

4.0 IMMEDIATE CORRECTIVE ACTIONS A Station Deviation Report was submitted documenting the verbatim compliance issue with the reactor trip bypass breaker surveillance testing.

5.0 ADDITIONAL CORRECTIVE ACTIONS The surveillance test procedures controlling the reactor trip bypass breaker testing were revised to ensure that bypass breakers are tested prior to placing them in service. The procedure requires the bypass breakers to be racked to the test position, the breaker closed, and then tripped open from the test panel.

Surveillance tests for Unit 1 and Unit 2 reactor trip bypass breakers were successfully completed following the revision to the surveillance procedures.

NRC FORM 366A (4-95)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION

• (4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION.

FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (3)

SURRY POWER STATION, Unit 1 YEAR I SEQUENTIAL NUMBER I REVISION NUMBER 05000 - 280 97 --011-- 00 40f 4 TEXT (If more space is required. use additional copies of NRC Form 366A) (17) 6.0 ACTIONS TO PREVENT RECURRENCE None 7.0 SIMILAR EVENTS None 8.0 ADDITIONAL INFORMATION None NRG FORM 366A (4-95)