Browse wiki

Jump to navigation Jump to search
ENS 41369
Show incoming properties 
Category
ENS Notification  and Power Reactor
CFR
10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat +, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition +, 10 CFR 50.72#b3iiB +  and 10 CFR 50.72#b3vB +
Current power
85  +
Current reactor mode
Power Operation +
Description
The licensee provided the following report … The licensee provided the following report via facsimile:</br>On February 3, 2005 at 1819 hours, Quad Cities Nuclear Power Station (QCNPS) confirmed a vulnerability with a 4160 VAC relaying and metering current transformer (CT) associated with the Unit and Reserve Auxiliary Transformers (i.e., the UAT and RAT) on both Unit 1 and Unit 2. Although the CT is currently fully operable, failure of the CT circuitry could cause the neutral overcurrent relay to trip and lockout the circuit breakers supplying feeds to safety related buses 13 (23) and 14 (24), isolating them from their normal and emergency power sources. Emergency power (i.e., the emergency diesel generator) would still be available to supply power to safety related buses 13-1 (23-1) and 14-1 (24-1), but the Residual Heat Removal Service Water (RHRSW) system may be without a source of power. If this failure occurred during a LOCA, then the RHRSW pumps may not be started within the ten minute requirement. A modification is in progress to eliminate this vulnerability. This event is being reported as a potential loss of safety function (10CFR50.72(b)(3)(v)(B)) and as a degraded or unanalyzed condition (10CFR50.72(b)(3)(ii)(B)).</br>The NRC Resident Inspector has been notified.</br>See similar events #41362 (Crystal River), #41366 (LaSalle), and #41370 (Dresden).), #41366 (LaSalle), and #41370 (Dresden).  +
Discovered date
00:19:00, 4 February 2005  +
Emergency class
Non Emergency +
Entered date
23:48:00, 3 February 2005  +
Event date
00:19:00, 4 February 2005  +
Event description
The licensee provided the following report … The licensee provided the following report via facsimile:</br>On February 3, 2005 at 1819 hours, Quad Cities Nuclear Power Station (QCNPS) confirmed a vulnerability with a 4160 VAC relaying and metering current transformer (CT) associated with the Unit and Reserve Auxiliary Transformers (i.e., the UAT and RAT) on both Unit 1 and Unit 2. Although the CT is currently fully operable, failure of the CT circuitry could cause the neutral overcurrent relay to trip and lockout the circuit breakers supplying feeds to safety related buses 13 (23) and 14 (24), isolating them from their normal and emergency power sources. Emergency power (i.e., the emergency diesel generator) would still be available to supply power to safety related buses 13-1 (23-1) and 14-1 (24-1), but the Residual Heat Removal Service Water (RHRSW) system may be without a source of power. If this failure occurred during a LOCA, then the RHRSW pumps may not be started within the ten minute requirement. A modification is in progress to eliminate this vulnerability. This event is being reported as a potential loss of safety function (10CFR50.72(b)(3)(v)(B)) and as a degraded or unanalyzed condition (10CFR50.72(b)(3)(ii)(B)).</br>The NRC Resident Inspector has been notified.</br>See similar events #41362 (Crystal River), #41366 (LaSalle), and #41370 (Dresden).), #41366 (LaSalle), and #41370 (Dresden).  +
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>.
ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +, ENS 41369 +  and ENS 41369 +
Hours
0.0211 d (0.505 hours, 0.00301 weeks, 6.921295e-4 months)  +
Initial power
85  +
Initial reactor mode
Power Operation +
Last update date
00:00:00, 4 February 2005  +
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>.
02:21:51, 2 March 2018  +
NRC officer
Bill Huffman +
Notification date
23:48:00, 3 February 2005  +
Originated by
Terry Gallentine +
Reactor critical
true  +
Reactor scram
false  +
Reactor type
GE-3 +
Region
NRC Region 3 +
Reporting criterion
10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat +  and 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition +
Reporting time
-0.0217 d (-0.52 hours, -0.0031 weeks, -7.12296e-4 months)  +
Site
Quad Cities +
Start date
00:19:00, 4 February 2005  +
State
Illinois +
System
Emergency Diesel Generator +  and Residual Heat Removal Service Water +
Title
4160 Volt Relaying and Metering Single Failure Vulnerability  +
Topic
Unanalyzed Condition +
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.
http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2005/20050207en.html#en41369  +
Unit
1  +  and 2  +
 
Retrieved from "https://kanterella.com/Special:Browse/:ENS-2041369"