IR 05000410/1987005

Insp Rept 50-410/87-05 on 870202-05.No Violations Noted. Major Areas Inspected:Msiv Control & Electrical Power Supplies

ML20205G881
Person / Time
Site:	Nine Mile Point
Issue date:	03/23/1987
From:	Anderson C, Paulitz F NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20205G850	List: IR 05000410/1987005 ML20205G844
References
50-410-87-05, 50-410-87-5, NUDOCS 8703310569
Download: ML20205G881 (6)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /87-05 Docket N License N NPF-54 Category B Licensee: Niagara Mohawk Power Corporation 300 Erie Boulevard, West Syracuse, New York 13202 Facility Name: Nine Mile Point, Unit No. 2 Inspection At: Scriba, New York Inspection Conducted: February 2-5, 1987 Inspector: Of0 h. f

'F. Raulitz, Reactor' Engineer

Date 3 7 Approved by: O 3 L1 /1 C. d. Anderson, Chief Plant Date Systems Section, EB, DRS Inspection Summary: Inspection on February 2-5, 1987 (Report N /87-05).

Areas Inspected: Routine, unannounced inspection of the licensee's main steam isolation valves control and electrical power supplies by one region based inspecto Results: No Violations were identified.

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PDR ADOCK 05000410 PDR

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a DETAILS 1.0 Persons Contacted 1.1 Niagara Mohawk Power Company

• R. Abbott, Station Superintendent M. Jones, Superintendent of Operation

• W. Connolly, QA Program Manager

• A. Pinter, Site Licensing Engineer A. Kovac, Quality First Program /QA Audits L. Fenton, Lead Audit Group

• J. Bunyan, Lead Electrical Engineer A. Julka, Electrical Engineer N. Kabarwal, Electrical Engineer 1.2 New York State Electric and Gas Corporation

• P. Macewan, Site Representative 1.3 Rochester Gas and Electric Corporation

• Larizza, Site Representative 1.4 New York State Power Service Commission

• P. Eddy, Site Representative 1.5 United States Nuclear Regulatory Commission

• Cook, Senior Resident Inspector Units 1&2

• Schmidt, Resident Inspector Units 1&2

• C, Marschall, Resident Inspector Units 1&2

Denotes those present at exit meeting on February 5,198 .0 Main Steam Isolation Valves 2.1 Background During the August 1986 Pre-operational testing of the Main Steam Isolation Valves (MSIV), valve 2 MSS *HYV78 failed to close within the 3-5 seconds required by the Technical Specifications. This Construc-tion Deficiency was reported by the licensee, as required by 10 CFR 50.55(e), on September 12, 1986. A final report on this problem was submitted by the licensee in October 1986. The response time deficiency was attributed to the design of the mechanical latching and actuating devic .

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The corrective action taken by the licensee was the replacement of the mechanical latching and actuation device with a different desig The new design utilized two tripping solenoids and a test solenoid for each of the four inboard and the four outboard MSIVs. These solenoids are designed to be energized to keep the MSIV open. Since the loss of either of the redundant power supplies would cause valve closure, the design incorporated into the Solenoid Operated Valve (SOV) provides an automatic power supply transfer. This transfer would detect a degraded power condition from either channel and dis-connect the degraded supply and reenergize the S0V from the other redundant suppl On December 3, 1986 this transfer was inadvertently actuated. During this transfer, the redundant channel power supplies were cross con-nected. This cross connection resulted in the loss of both supplie These power supplies are also utilized by the Reactor Protection System (RPS) Channel This failure which caused a reactor scram was reported by the licensee, as required by 10CFR 50.73, on December 23, 198 The licensee met with the Office of Nuclear Reactor Regulation (NRR) staff on December 18,1986 to discuss the problem identified on December 3, 1986. Additional meetings were held on this subject on December 22, 1986 (telecon), January 6,1987, and January 9,1987 (telecon). The NRC Safety Evaluation related to the MSIV Actuation Logic Design sent to the licensee, by letter dated January 14, 1987, concluded that the automatic transfer of MSIV logic power from one safety related chan-nel to the other was unacceptabl .2 Design Modification In a letter dated January 15, 1987 the licensee proposed a modifi-cation which would eliminate the auto transfer feature discussed above. Also, in this letter, the licensee provided information con-cerning issues raised during the January 9, 1987 telephone. conference with NRR. These issues are as follows:

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l Qualification of the ITE/Telemechanique (Gould) relay type J10 used for cross channel trip isolation.

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Control of fuse replacement for the double fuses used as iso-lation devices.

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Safety-related S0V testin *

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Testing of the MSIVs I

j A followup meeting was held on January 28, 1987 with NRR. A telecopy

letter was sent to NRR on February 2, 1987 providing the following l information

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The licensee would test the Gould relay in accordance with the procedure sent to NRR.

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The licensee has a Station Administrative Procedure to control the replacement of fuse *

The safety-related solenoids have a reed switch associated with an indication light on the main control board. This indication I can be used to verify operabilit *

The MSIVs are required to be full stroke tested per ASME Section XI,part IWV 3412. The above ASME code is a requirement of the Technical Specification 4. .

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2.3 Inspection Scope This inspection was to review the licensee actions resulting from the NRR concerns mentioned abov ,

"1 2.4 Findings The following are findings associated with this inspection:

A maximum credible fault test of the Gould J10 relay was con-ducted by the licensee on February 3, 1987. The test was de-

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signed to duplicate failures which could occur between the relay coil and its contacts. TF normal coil failure mechanism is due to progressive heating resulting from degraded insulation and shorted coil wires. This heating of the coil could affect the contacts. This degraded coil condition occurs over a long time period. The end of life condition coil temperature was achieved by a gradual increase in the voltage applied to the coil. The maximum voltage applied was 360 volt This voltage caused the current to increase from a design current of 0.133 ampere to ampere. This current increase to 70 times rated current caused

the coil winding to open circuit. This had no effect on the contacts. The inspector reviewed the test procedure, test set-

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up, relay condition after the test, and preliminary test dat No deficiencies were identifie !

The licensee has a Standing Order, #14 " Operations Department Fuse Control Program", Revision 0, which should preclude the improper replacement of the fuses used for electrical isolation of the test solenoid and its circuits from the safety related *

l power supply. The inspector has reviewed this procedure. No '

deficiencies were identified.

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The licensee provided the inspector with a Technical Manual for Target Rock Corporation Solenoid Operated Valves. This manual is not specific for the 50Vs associated with the MSIVs.

, However, it does indicate that the reed switch is only actuated by movement of the solenoid plunger. A review of the vendor, EPG, MSIV Elementary Diagram No. 2538-E-1101, Revision K,

indicated that when both the A & B SOV are closed a green i

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light is illuminated. When both solenoids are open a red light is illuminated. The inspector determined that the design pro-vides a means to verify that the redundant trip solenoids have inde-pendently ope. rated upon demand. The verification of these lights by the control room operator is required prior to open-ing of the MSIV to assure that the redundant solenoids have served their safety functio The inspector determined that this verification is required in Operating Procedure for Main Steam System No. N2-0P-1, Revision 0, Revision 1 Draft, Section 1.0 MSIV Open Operation and Section 2.0 MSIV Close Operatio *

The MSIVs as presently designed can not be tested using the trip solenoids without causing complete valve closure because the design does not have means of preventing the oil dump when either trip solenoid is deenergized. This is a fail safe de-sig *

The Technical Specification (TS) 4.4.7 Surveillance Requirements requires that the MSIVs shall be demonstrated OPERABLE by veri-fying full closure between 3 and 5 seconds when tested pursuant to Specification 4. Surveillance Requirement 4.0.5(a) states in part that .. Inservice Inspection of ASME Code Class 1,2 & 3 components shall be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Cod ASME Section XI - Inservice inspection of Nuclear Power Plant Com-ponents Section Article IWV-3410 Valve Exercising Test states in part that... fail-safe valves which can not be tested every three (3)

months shall be tested during each cold shutdown not to exceed more than every three (3) month The inspector discussed with the licensee the TS requirements of MSIV testing and the TS requirement for testing of the logic power supply, Electrical Protective Assembly (EPA). The EPA surveillance test fre-quency is every six (6) months. Opening of the EPA breaker will cause MSIV closur In addition, the inspector observed that the failure of any normally energized (8) test solenoid and the (32) isolation fuses would cause an MSIV closure and a potential unit trip. It appeared to the inspector that this design is subject to failure resulting in unnecessary challenges to safety systems. This observation was discussed with the license The EPA surveillance test and the susceptability of the MSIV control system to excessive MSIV closure and unit trip is unresolved item 50-410/87-05-0 .

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3.0 Exit Interview An exit interview was held on February 5, 1987 with members of the licen-see staff, denoted in Paragraph 1, at the conclusion of the inspectio The inspector summarized the scope and findings of the inspection at that tim No written material was provided to the licensee by the inspector.