ML20214K283

Special Rept 86-005:on 861018,19 & 31,ESF Switchgear Rooms I & II Exceeded Max Temp Limit Specified in Tech Specs. Caused by Inoperability of Cooling Unit

ML20214K283
Person / Time
Site:	Wolf Creek
Issue date:	11/18/1986
From:	Koester G KANSAS GAS & ELECTRIC CO.
To:	Martin R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
86-005, 86-5, KMLNRC-86-221, NUDOCS 8612020247
Download: ML20214K283 (3)

Text

W .i KANSAS GAS AND ELECTRIC COMPANY T&4E ELECTRC COMPANY otrun t norstra November 18, 1986 W4Cf PetSJOINT NUCLEAR Hr. R. D. Martin, Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000

@@MOMM W Arlington, Texas 76011 U '

KMLNRC 86-221 Re: Docket No. STN 50-482 Subj: Special Report 86-005

Dear Mr. Martin:

The enclosed Special Report is submitted pursuant to Technical Specifications 6.9.2 and 3.7.12.

Yours very truly, 4Lau -

Glenn L. Koester Vice President - Nuclear GLK:see cc: P0'Connor (2)

JCummins 8612O20247 861118 PDR ADOCK 05000482 S PDR -

QV 11k 6 1

201 N. Market - Wictuta, Kansas - Mail Address: PO. Box 208 I Wichita, Kansas 67201 - Telephone: Area Code (316) 261-6451

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SPBCIAL REPORF 86-995 AREA TI!MPERATURE LIMIT ExmFPFn on October 19, 1986, the temperature in Engineered Safety Features (ESF)

Switchgear Room II exceeded the maximum temperature limit specified in Technical Specification 3.7.12 for more than eight hours. On October 31, 1986, the temperature in ESF Switchgear Room I also exceeded this temperature limit. Wis Special Report is being subnitted pursuant to Technical Specifications 6.9.2 and 3.7.12, Action Statement 'a', and contains details of the time and amount by which the temperature exceeded the limit and information concerning continued operability of the affected equipment.

On October 18, 1986, at approxircately 2020 Car, the ESF Switchgear Room II Cooling unit, SGK05B, ceased to operate. This allowed the Room II temperature to briefly exceed the 87 degree Fahrenheit limit specified in Technical Specification 3.7.12. Plant personnel began monitoring the room temperature on an hourly basis, and various doors were opened and fans started in an attempt to cool the room. At approximately 2110 CDP, the temperature had decreased to 84 degrees Fahrenheit and remained below the 87 degree limit until approximately 0715 CUT on October 19, 1986, at which time the limit was exceeded for approximately 40 minutes. At approximately 1204 CDP, the temperature rose to 88 degrees Fahrenheit and remained above the 87 degree limit until approximately 1800 CDT on October 20. From this time until restoration of the roan cooler to service at approximately 1235 CST, on Ibvember 1,1986, the room temperature was intermittently above 87 degrees Fahrenheit.

Between October 19 and tbvember 1 at 1300 CST, the temperature in ESF Switchgear Room II exceeded the Technical Specification limit for-approximately one hundred hours. The temperature was within the limit for approximately two hundred and twenty four hours. The temperature reached a maximum of 100 degrees Fahrenheit on November 1, 1986, at approximately 0100 CST, and remained at this elevated temperature for approximately one hour.

The average room temperature throughout this period was 87.4 degrees Fahrenheit.

On October 31, 1986, at approximately 0828 CST, the room cooler in ESP Switchgear Room I also ceased to function properly. This resulted in the temperature in ESF Switchgear Room I also exceeding the Technical Specification temperature intermittently between approximately J900 CST on October 31 until 0100 CST on Ibvember 1,1986. Plant personnel r:onitored the temperature in ESF Switchgear Room I on an hourly basis during this time period.

During this time period, the temperature in Room I exceeded the lin.it for approximately nineteen hours, and was within the temperature limit for approximately ten hours. We temperature averaged 89.2 degrees Fahrenheit and reached a maximum of 97 degrees Fahrenheit at approximately 0400 CST on November 1, and remained at this elevated temperature for approximately two hours.

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W e normal opercting temperature for the ESF Switchgear Rooms varies from 60 degrees Fahrenheit (minimum) to 90 degrees Fahrenheit (maximum) . It is

- noted that the Technical Specification area temperature limitation of 87 degrees includes an allowance for instrument error of plus or minus 3 degrees Fahrenheit. Safety related equipnent and components within the ESF Switchgear Rooms include redundant trains of 4.16 kilovolt switchgear, 480 volt load centers,.a 480 volt motor control _ center, load center transformers,'an auxiliary relay rack, lockout relay racks, local control' stations, Control Roan isolation protection cabinets, and heating, ventilating and air conditioning system isolation dampers. We components with the most limited operating temperature conditions are the 480 volt load centers, 480 volt load center transformers, 480 volt motor control center and 4.16 kilovolt switchgear. These components can' tolerate service conditions up to 104 degrees Fahrenheit. We other equipment is capable of withstanding temperatures of 110 degrees to 120 degrees Fahrenheit for specified durations. Because these limits were not exceeded during-this event, it is concluded that the temperature deviation had no detrimental effect on the equipment contained in ESF Switchgear Rooms, r Special Report 86-003 discusses a previous occurrence of the temperature in ESF Switchgear Room II exceeding the Technical Specification temperature limit.

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