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During a review it was determined that theDuring a review it was determined that the Diesel Generator load calculation (EA-ELEC-LDTAB-005) did not account for worst case load from the Containment Air Cooler Fan Motors (V-1A, V-2A, V-3A). Initial review indicates that with the worst case fan motor loading, Diesel Generator 1-2 could be loaded beyond its 2 hour rating following a Loss of Coolant Accident (LOCA) during the time period prior to Recirculation Actuation (RAS).</br>The horsepower loading for the motors used in the Diesel Generator load calculation was based on the original specification for the motors. In 1993 calculation EA-DPAL93-110 was done to determine the impact of partial flooding of the air coolers coils on the cooling fan performance. The 1993 calculation calculated a fan motor load that was higher than what is used in the diesel generator load calculation. However, the diesel generator load calculation was not updated as a result of the 1993 calculation.</br>The higher motor power requirement is 17 kW per fan. There are 3 Containment Air Cooler fans loaded on Diesel Generator 1-2. The extra loading, when combined with the possible additional load from operating the diesel generator at increased frequency, raises the calculated load to 2782 kW, which is above the 2 hour rating of 2750 kW. The overload only applies during a time segment of the diesel generator load profile prior to RAS. This could result in the loss of the diesel generator. </br>There is only 1 Containment Air Cooler Fan Motor (V4A) loaded on Diesel Generator 1-1 and has 121 kW margin available. Therefore, there is no concern about overloading Diesel Generator 1-1.</br>Placed hand switches (42-299CS & 42-277CS) for Turbine Generator Emergency Air Side Seal Oil Backup Pump (P-23) and Turbine Turning Gear Oil Pump (P-26) in Pull-To-Lock position, which prevents the pumps from automatically starting. This reduces the potential load on 1-2 D/G by 71 kW. This restores the load on the diesel to within the margin.</br>Licensee has notified the NRC Resident Inspector</br>* * * RETRACTION AT 1416 EST ON 12/30/08 FROM DAVIS TO HUFFMAN * * *</br>Entergy Nuclear Operations Inc. (ENO) is retracting Event Notification EN #44645 which reported a loss of a safety function due to the 1-2 emergency diesel generator (EDG) load calculation not accounting for the worst-case load from the containment air cooler fan motors. The initial review indicated that, with the worst-case fan motor loading, the 1-2 EDG could have been loaded beyond the 2750 kW two-hour peak loading limits following a loss-of-coolant accident during the time period prior to a recirculation actuation signal. This condition may have caused 1-2 EDG to become inoperable, and could have prevented fulfillment of a safety function.</br>In a subsequent evaluation of loading capability, completed on December 18, 2008, ENO determined the 1-2 EDG was operable. The EDGs are rated for 2750 kW two-hour peak operation. It was determined that the postulated peak load for the 1-2 EDG would have been 2819 kW for a period of approximately thirty-eight minutes. However, based on engineering information obtained from the vendor of the 1-2 EDG, Fairbanks-Morris Engine, and reviewed by ENO, the 1-2 EDG could have been operated up to 2830 kW for fifty minutes before any susceptibility to damage might occur. In addition, under the peak loading condition of 2819 kW, the speed of the 1-2 EDG would have remained above the Technical Specification limit of 59.5 Hz. The subsequent review confirmed that the safety function would have been fulfilled. Therefore, ENO is retracting this event notification.</br>The licensee has notified the NRC Resident Inspector. R3DO (Cameron) notified. Resident Inspector. R3DO (Cameron) notified.  
19:41:00, 7 November 2008  +
44,645  +
22:00:00, 7 November 2008  +
19:41:00, 7 November 2008  +
During a review it was determined that theDuring a review it was determined that the Diesel Generator load calculation (EA-ELEC-LDTAB-005) did not account for worst case load from the Containment Air Cooler Fan Motors (V-1A, V-2A, V-3A). Initial review indicates that with the worst case fan motor loading, Diesel Generator 1-2 could be loaded beyond its 2 hour rating following a Loss of Coolant Accident (LOCA) during the time period prior to Recirculation Actuation (RAS).</br>The horsepower loading for the motors used in the Diesel Generator load calculation was based on the original specification for the motors. In 1993 calculation EA-DPAL93-110 was done to determine the impact of partial flooding of the air coolers coils on the cooling fan performance. The 1993 calculation calculated a fan motor load that was higher than what is used in the diesel generator load calculation. However, the diesel generator load calculation was not updated as a result of the 1993 calculation.</br>The higher motor power requirement is 17 kW per fan. There are 3 Containment Air Cooler fans loaded on Diesel Generator 1-2. The extra loading, when combined with the possible additional load from operating the diesel generator at increased frequency, raises the calculated load to 2782 kW, which is above the 2 hour rating of 2750 kW. The overload only applies during a time segment of the diesel generator load profile prior to RAS. This could result in the loss of the diesel generator. </br>There is only 1 Containment Air Cooler Fan Motor (V4A) loaded on Diesel Generator 1-1 and has 121 kW margin available. Therefore, there is no concern about overloading Diesel Generator 1-1.</br>Placed hand switches (42-299CS & 42-277CS) for Turbine Generator Emergency Air Side Seal Oil Backup Pump (P-23) and Turbine Turning Gear Oil Pump (P-26) in Pull-To-Lock position, which prevents the pumps from automatically starting. This reduces the potential load on 1-2 D/G by 71 kW. This restores the load on the diesel to within the margin.</br>Licensee has notified the NRC Resident Inspector</br>* * * RETRACTION AT 1416 EST ON 12/30/08 FROM DAVIS TO HUFFMAN * * *</br>Entergy Nuclear Operations Inc. (ENO) is retracting Event Notification EN #44645 which reported a loss of a safety function due to the 1-2 emergency diesel generator (EDG) load calculation not accounting for the worst-case load from the containment air cooler fan motors. The initial review indicated that, with the worst-case fan motor loading, the 1-2 EDG could have been loaded beyond the 2750 kW two-hour peak loading limits following a loss-of-coolant accident during the time period prior to a recirculation actuation signal. This condition may have caused 1-2 EDG to become inoperable, and could have prevented fulfillment of a safety function.</br>In a subsequent evaluation of loading capability, completed on December 18, 2008, ENO determined the 1-2 EDG was operable. The EDGs are rated for 2750 kW two-hour peak operation. It was determined that the postulated peak load for the 1-2 EDG would have been 2819 kW for a period of approximately thirty-eight minutes. However, based on engineering information obtained from the vendor of the 1-2 EDG, Fairbanks-Morris Engine, and reviewed by ENO, the 1-2 EDG could have been operated up to 2830 kW for fifty minutes before any susceptibility to damage might occur. In addition, under the peak loading condition of 2819 kW, the speed of the 1-2 EDG would have remained above the Technical Specification limit of 59.5 Hz. The subsequent review confirmed that the safety function would have been fulfilled. Therefore, ENO is retracting this event notification.</br>The licensee has notified the NRC Resident Inspector. R3DO (Cameron) notified. Resident Inspector. R3DO (Cameron) notified.  
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2.314815e-5 d (5.555556e-4 hours, 3.306878e-6 weeks, 7.61e-7 months)  +
00:00:00, 30 December 2008  +
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>.
02:12:57, 2 March 2018  +
22:00:00, 7 November 2008  +
false  +
0.0967 d (2.32 hours, 0.0138 weeks, 0.00318 months)  +
true  +
19:41:00, 7 November 2008  +
Load Calulations for Edg Were Incorrect  +
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.
1  +