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This 60-day telephone notification is bein … This 60-day telephone notification is being submitted in accordance with paragraphs 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A) to report an invalid actuation of the Auxiliary Feedwater (AFW) system at Watts Bar Nuclear Plant Unit 1.</br>On March 17, 2015, at 1306 EDT, Watts Bar Unit 1 was in Mode 1 at 100% power, when during the performance of 6.9 Kv phase verifications for the FLEX Diesel Generator, maintenance technicians were installing a multimeter (Simpson 260 Series) which resulted in starting the Unit 1 train B: motor-driven auxiliary feedwater pump, centrifugal charging pump, component cooling pump and thermal barrier booster pump, and isolated steam generator 1 and 3 blowdown. A secondary 6 ampere fuse opened due to an overcurrent and actuated (dropped-out) the associated blackout relays which started the identified pumps. At the time of the event, the train B standby diesel generator was removed from service for maintenance. The 6.9 Kv shutdown board did not lose power during the event and safety injection system and standby diesel generator features were not actuated. </br>The maintenance technicians performing the phase verifications immediately recognized that several supply breakers had closed after the last test lead was connected and promptly reported the event to the control room. Work was halted and TVA conducted a prompt investigation. While not conclusive, it is likely that the maintenance technicians created a shunt or ground condition while installing test equipment, causing a circuit overcurrent which opened the fuse, activating the black-out relays and actuating the identified pumps and valves. Plant operators responded appropriately to the event and the applicable Technical Specification Required Actions were exited at 1612 EDT, when equipment restoration had been completed. TVA is continuing to evaluate this event in accordance with the corrective action program (reference: PER nos.1003213 and 1027101).</br>The NRC Resident Inspector has been notified. NRC Resident Inspector has been notified.
17:06:00, 17 March 2015 +
51,079 +
15:45:00, 18 May 2015 +
17:06:00, 17 March 2015 +
This 60-day telephone notification is bein … This 60-day telephone notification is being submitted in accordance with paragraphs 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A) to report an invalid actuation of the Auxiliary Feedwater (AFW) system at Watts Bar Nuclear Plant Unit 1.</br>On March 17, 2015, at 1306 EDT, Watts Bar Unit 1 was in Mode 1 at 100% power, when during the performance of 6.9 Kv phase verifications for the FLEX Diesel Generator, maintenance technicians were installing a multimeter (Simpson 260 Series) which resulted in starting the Unit 1 train B: motor-driven auxiliary feedwater pump, centrifugal charging pump, component cooling pump and thermal barrier booster pump, and isolated steam generator 1 and 3 blowdown. A secondary 6 ampere fuse opened due to an overcurrent and actuated (dropped-out) the associated blackout relays which started the identified pumps. At the time of the event, the train B standby diesel generator was removed from service for maintenance. The 6.9 Kv shutdown board did not lose power during the event and safety injection system and standby diesel generator features were not actuated. </br>The maintenance technicians performing the phase verifications immediately recognized that several supply breakers had closed after the last test lead was connected and promptly reported the event to the control room. Work was halted and TVA conducted a prompt investigation. While not conclusive, it is likely that the maintenance technicians created a shunt or ground condition while installing test equipment, causing a circuit overcurrent which opened the fuse, activating the black-out relays and actuating the identified pumps and valves. Plant operators responded appropriately to the event and the applicable Technical Specification Required Actions were exited at 1612 EDT, when equipment restoration had been completed. TVA is continuing to evaluate this event in accordance with the corrective action program (reference: PER nos.1003213 and 1027101).</br>The NRC Resident Inspector has been notified. NRC Resident Inspector has been notified.
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100 +
00:00:00, 18 May 2015 +
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>.
01:47:43, 2 March 2018 +
15:45:00, 18 May 2015 +
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61.944 d (1,486.65 hours, 8.849 weeks, 2.036 months) +
17:06:00, 17 March 2015 +
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.