The licensee notified the NRC Resident Inspector and will notify the State of
To top of pagePower Reactor Event Number: 45848
Region: 1 State: NJ
Unit:  [ ] [ ]
RX Type:  W-4-LP, W-4-LP
NRC Notified By: MATT MOG
HQ OPS Officer: HOWIE CROUCH Notification Date: 04/16/2010
Notification Time: 22:08 [ET]
Event Date: 04/16/2010
Event Time: 16:41 [EDT]
Last Update Date: 04/16/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
MEL GRAY (R1DO)
Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N N 0 Refueling 0 Refueling
Event Text UNPLANNED EMERGENCY DIESEL GENERATOR START DUE TO LOSS OF A 4160 V BUS
"At 1641 hours [EDT] on April 16, 2010, an [unplanned] automatic start signal was generated for the 1C Emergency Diesel Generator (EDG). Surveillance testing was being performed on the 1C 4160 volt bus to verify the ability to swap between the 13 and 14 Station Power Transformers (SPT) which are the offsite power in-feeds for the 1C 4160 volt bus. The [failure to] swap from the 13 SPT to 14 SPT resulted in a loss of power to the 1C 4160 volt vital bus generating the automatic start signal for the 1C EDG. The 1C EDG started but the output breaker did not close. Abnormal operating procedure S1.OP-AB.4KV-0003 was entered for loss of the 1C 4160 volt vital bus. Salem Unit 1 was in Mode 6 with core reload (fuel movement) in progress. Fuel movement was stopped as a result of the loss of the 1C 4160 volt bus. All fuel assemblies were placed in a safe position. There was no impact to shutdown cooling and no loss of spent fuel pool cooling. Core reload has been suspended until power is restored to the 1C 4160 volt bus. Initial investigations determined the suspected cause to be a failed auxiliary contact associated with a SPT in-feed breaker. This prevented the opposite in-feed and EDG breaker from closing. Extent of condition review and repairs are in progress."
Fuel movement was suspended due to loss of the fuel handling building exhaust fan which is powered by the 1C 4160V bus. There was no further impact on any safety related equipment required in Mode 6.
The license will notify the NRC Resident Inspector, Lower Alloways Creek Township, the State of New Jersey, and the State of Delaware.