United States Nuclear Regulatory Commission - Protecting People and the Environment

LICENSEE: SYNCHRO-START CORPORATION
SITE: COLTEC INDUSTRIES EN NUMBER: 35369
DOCKET: EVENT DATE: 01-20-99
RX TYPE: EVENT TIME:
VENDORS: NOTIFY DATE: 02-15-99
EMERGENCY CLASS: N/A REGION: 3 STATE: WI TIME: 15:26
OPS OFFICER: LEIGH TROCINE
10 CFR SECTION: CCCC UNSPECIFIED PARAGRAPH
10-CFR-PART-21 NOTIFICATION FROM COLTEC INDUSTRIES, FAIRBANKS MORSE ENGINE DIVISION, REGARDING SYNCHRO-START -- ESSB-4AT SPEED SWITCHES, MODEL SA2110

The following text is a portion of a facsimile received from the Coltec Industries:

"On January 20, 1999, Coltec Industries, Fairbanks Engine Division (FMED), became aware of a potential safety hazard associated with the Synchro-Start -- ESSB-4AT speed switches supplied to PSE&G -- Hope Creek Nuclear Power Station. FMED had supplied four Synchro-Start ESSB-4AT Model-SA2110 speed switches to Hope Creek in late 1997 and early 1998, which malfunctioned after approximately 70 hours of energization. Hope Creek had previously evaluated the failures as not being a substantial safety hazard.

"In the ... root cause investigation, FMED evaluated the starting circuitry and confirms that this is not a substantial safety hazard at Hope Creek due to redundant circuitry. However, the investigation revealed that it is likely that one more ESSB-4AT Model-SA2 110 speed switch manufactured by Synchro-Start may have been supplied to the nuclear industry or non-nuclear application by a supplier other than Coltec Industries. The list of possible recipients of the suspect speed switch are: Wolf Creek Nuclear, Engine Systems Inc, Florida Keys Electric, Interstate Power Company, Rolls Royce, and Traycanna. Therefore, notification is being made of the potential substantial safety hazard that might exist at other nuclear facilities that have purchased an ESSB-4AT speed switch in late 1997 and early 1998.

"The Engineering Report also determined the root cause of the speed switch failures to be personnel error at Synchro-Start. A personnel error was made by picking the wrong current limiting resistor from stock for installation into the speed switch power supply circuit card. Corrective actions have been taken by Synchro-Start to prevent recurrence including moving the stock location of the resistors, retraining personnel, and changing procedures to verify proper resistor during bench testing.

The Engineering Report from Coltec Industries also stated, "While the degradation described in the Part 21... pertains only to PSE&G at Hope Creek and the ESSB-4AT speed switch, Coltec Engineering has also evaluated the applicability to other power stations that use a similar speed switch, such as models ESSB-2AT and --3AT, in a similar circuit arrangement. These other models of speed switch would also use the same internal power supply. Coltec identifies the power stations listed below. It should be noted that Hope Creek is the only installation that employs the ESSB-4AT for speed switch requirements. Coltec has not been notified of any other speed switch degradations at any of the other nuclear power stations; Hope Creek is the only instance.

Alabama Power--Farley
Entergy--Arkansas Nuclear One
Georgia Power--Hatch I
Detroit Edison--Fermi 2
Northeast Utilities--Millstone 3
Public Service New Hampshire--Seabrook
Angra Brazil
Duquesne Light--Beaver Valley
SCE&G--V C Summer
PECO--Limerick
Union Electric--Callaway
Kansas Gas and Electric--Wolf Creek
PSE&G--Hope Creek

"Coltec Engineering has also reviewed the starting circuitry for the above mentioned power stations. All of the above stations have the similar redundant starting circuitry found at Hope Creek with four exceptions. The four exceptions are Alabama Power, Detroit Edison, Northeast Utilities, and Angra Brazil. At these four plants, if the installed speed switch should fail, the diesel would then fail to start, because of the failed speed switch, and not perform its intended design function. At this time, there is no substantive safety hazard because none of these plants have received any suspect speed switches.

"Therefore, this investigation and finding at Hope Creek is not considered a substantial safety hazard as defined by [10 CFR] Part 21. This is due to the redundancy in the starting circuitry. However, since there may be one remaining speed switch with an improper internal power supply, there may be a safety hazard depending on the configuration of the starting circuitry and the incorporation of redundancy at that site."

(Call the NRC operations officer for a contact address and telephone number.)


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