ML20024C665
| ML20024C665 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 12/08/1977 |
| From: | Herbein J METROPOLITAN EDISON CO. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20024C648 | List: |
| References | |
| REF-SSINS-6820, REF-SSINS-SSINS-6, TASK-*, TASK-GB GPU-2052, GQL-1699, IEB-77-05, IEB-77-5, NUDOCS 8307120938 | |
| Download: ML20024C665 (2) | |
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METROPOLITAN EDISON COMPANY suaspuarokceneanrusucununssconminan Po37 OFFICE sox 542 READING, PENNSYLVANIA 19603 TELEPHONE 215 -929 3801 December 8.1977 o g 1699 Mr. B. H. Grier, Director U. S. Nuclear Regulatory Co=sission Regio ~n 1 631 Park Avenue King of Prussia,' Pennsylvania 19k06
Dear Sir:
Three Mile Island Nuclear Station Unit 1 T.'II-1 Response to II Bc11stin No. 77-05 Enclosed please find Metropolitan Edisod's response to I.I'. Bulletin No. 77-05 concerning the failure of pin and socket type electrical connectors in a post LOCA containment environ =ent.
In light of the fact tha't the supple =ent to I.E. Bulletin T7-05 (I.E.
Bulletin 77-05A) was received by Met-Ei on November 16, 1977, and because s'. additional analysis is required to formulate a response to that supple-
. ment, Met-Ed vill respond to I.E. Bulletin 77-05A by December l'6,1977 We trust this submittal to be satisfactory, however, should you have ary additional questions please contact me.
Sincerely, i
$sned J. G.'Herbeln f
J. G.-Herbein Vice President JGH:RAL:tas Enclosure cc:
U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Division of Reactor Construction Inspection Washington, D.C.
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8307120938 771100' PDR ADDCK 05000289 G
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Enclosuro to GQL 1 W g.'
Metropolitan Edison Company
,Three Mile Island, Nuclear Stationy Unit 1
]
I.E. Bulletin No. 77-05 '
R'eceht tests conducted by Sandia Laboratories of electrical connect'or/ cable assemblies in a si=ulated post LOCA containment environment (LWR) demonstrated Metropolitan that the assemblies failed to perform in an acceptable manner.
Edison Generation Engineering has reviewed the TMI,1 safety'systens which are located within containcent, and therefore could be subjected to a post LOCA
.contain:nent environment., These systems are as follows:
I.
Eriineered Safeauards ictuated Ecuissent Ai!-E-2A/B/C RS-V-35 IC-V2
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AH-V1B/C
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W-Y25 CF-V2A/B CA-71,3,hA/B,13 WDL-V303 II. Reactor Protection Systens l."
A.
Neutres Detectors
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B'.
Reactor Coolant Pressure Transsitters C.
Reactor Outlet Te=perature RTD's Potential and C61rrent Transformers for Reactor
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D.
C,oolant Pu=y Power Monitors
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Reactor Coolant Flow Ele =ents E.
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'III Tncineeied' Safe.tdards Aci;dat15n'instz'une'ntation A.
Reactor Coolant Pressure Transmitters The connectors which were tested by Sandia Laboratories, and found to be deficient TMI-1 does not were of the. pin and socket type, with metal shell and screw couplings.
These
'use any pin / socket cennectors for any power or control cable connections.
connections are made by "hard viring". (i.e. teminal blocks, which are inside either motor terminal boxes or DAI terminal boxes).
Of the safety. syste=s listed above, pin and soc $et type connectors are used only in Neither the the control rod drite mechanisns (CRDM) and in the neutron detectors.
CRD'4 nor the neutron detectors are. required to operate ddring a LOCA.
It should be noted, The CRD?f vill trip upon loss of power initiated by a resctor trip Additionally, a failure of.a connector on a control rod position indicator vould produce a false reading which'vould initiate,a non-safety related alarm position.
indication.
These detectors provide Neutron detectors are not required to operate during a LOCA.
It input to the Reactor Protection System, as a safety system, during operation.used shonid also be noted that the electrical connectors I
neutron detectors are nanufactured' by a different company than those which were by Sandia Laboratories.
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