Browse wiki
Jump to navigation
Jump to search
This event is being reported in accordance … This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A), an event or condition that resulted in a valid actuation of emergency AC electrical power systems.</br>At 0104 EDT on November 5, 2010, the plant was in Mode 5 Cold Shutdown in a refueling outage. Maintenance personnel were performing post maintenance testing on the main generator relay panel when the 'B-SB' Safety Bus was inadvertently de-energized, resulting in automatic starting of the 'B-SB' Emergency Diesel Generator. Safety systems responded as expected during the event, and the 'A-SA' Emergency Bus remained operable with power available from both offsite power and the 'A-SA' Emergency Diesel Generator throughout the event. The 'B-SB' Safety Bus was powering shutdown cooling, which was restored using 'B-SB' Residual Heat Removal system at 0107 EDT with the 'B-SB' Emergency Diesel Generator supplying the bus. The testing procedure was not intended to result in the safety bus being de-energized nor automatic start of the Emergency Diesel Generator. Although the specific cause of the safety bus being de-energized is not known at the present time, it appears that it was directly related to the testing being performed.</br>The licensee notified the NRC Resident Inspector.</br>The 'B-SB' Safety Bus has been returned to its normal offsite power source and the 'B-SB' Emergency Diesel Generator secured and returned to standby status.or secured and returned to standby status. +
05:04:00, 5 November 2010 +
46,396 +
06:50:00, 5 November 2010 +
05:04:00, 5 November 2010 +
This event is being reported in accordance … This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A), an event or condition that resulted in a valid actuation of emergency AC electrical power systems.</br>At 0104 EDT on November 5, 2010, the plant was in Mode 5 Cold Shutdown in a refueling outage. Maintenance personnel were performing post maintenance testing on the main generator relay panel when the 'B-SB' Safety Bus was inadvertently de-energized, resulting in automatic starting of the 'B-SB' Emergency Diesel Generator. Safety systems responded as expected during the event, and the 'A-SA' Emergency Bus remained operable with power available from both offsite power and the 'A-SA' Emergency Diesel Generator throughout the event. The 'B-SB' Safety Bus was powering shutdown cooling, which was restored using 'B-SB' Residual Heat Removal system at 0107 EDT with the 'B-SB' Emergency Diesel Generator supplying the bus. The testing procedure was not intended to result in the safety bus being de-energized nor automatic start of the Emergency Diesel Generator. Although the specific cause of the safety bus being de-energized is not known at the present time, it appears that it was directly related to the testing being performed.</br>The licensee notified the NRC Resident Inspector.</br>The 'B-SB' Safety Bus has been returned to its normal offsite power source and the 'B-SB' Emergency Diesel Generator secured and returned to standby status.or secured and returned to standby status. +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
00:00:00, 5 November 2010 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
02:08:29, 2 March 2018 +
06:50:00, 5 November 2010 +
false +
false +
0.0738 d (1.77 hours, 0.0105 weeks, 0.00242 months) +
05:04:00, 5 November 2010 +
Valid Actuation of an Emergency Diesel Generator Following Inadvertent De-Energization of Safety Bus +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.