ML20024C676
| ML20024C676 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 12/15/1977 |
| From: | 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-1719, IEB-77-05A, IEB-77-5A, NUDOCS 8307120949 | |
| Download: ML20024C676 (2) | |
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1 METROPOLITAN EDISON COMPANY suostormoraenensuusucununesconmancu Post office SOX 542 READING. PENNSYLVANIA 19603 TELEPHONE 215-929 3601 December 15,1977 0% 1719 Mr. B. E. Grier Director Office of Inspection & Enforcements, Region I U. S. Nuclear Regulatory Conmission 631 Park Avenue 19406 I
King of Prussia, Pennsylvania
Dear Sir:
,p Three Mile Island Nuclear Station, Unit 1 (TMI-1) operating License No. DPR-50 Docket No. 50-289 IE Bulletin No.77-05A In response to IE Bulletin No. 77-05, Metropolitan Edison Compary reviewed the TMI-1 safety systems as indicated in our letter GQL 1699 of December 8, In response to IE Bulletin TT-05A, Met-Ed expanded its review of the 1977 TliI-1 safety systems to include all connectors which are required to function l
to mitigate an accident where the accident itself could adversely affect the This review included ability of the system to perform its safety function.
areas outside of containment as well as conditions other than a LOCA.
As indicated in our response to IE Bulletin 77.-05, the only electrical con-nector assemblies concerned are those used for the control rod drive mecha-
~
Of these two areas of concern,.
n' isms (CRDM's) and the neutron detectors.
only the neutron detectors require further discussion, since any power failure As stated in our to the CRDM results in a fully inserted rod condition.
letter GQL 1699, it should be'noted that the electrical connectors used in conjunction with the neutron detectors are manufactured by a different com-pany than those which vere tested by Sandia Laboratories.
8 The Power Range Nuclear Instruments (NI's) are supplied with TRIAX connectors.
08 These connectors are located inside the detector thimble tube and sealed wit Ray Chem shrinkable tubing over the connector. the assembly,is further sealed No h
b by the refueling canal cover plate which is sealed with a %" natural rubber o
gasket and silicon RTir sealant. According to the vendor of these# assemblies, gg The the connectors have been qualified to a design temperature of 200 F.
- g cuo NI's utilize connector assemblies located in terminal boxes at the contain-7 These ment elec'trical penetrations both inside and outside of containment.
electrical penetrations are located on the south side of containment and coa.e IEEE 279 separation criteria has been met. Since the Main Steam and Feed-Pr9rRJBm enter containment on the north side, these penetrations are not
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. R. 8. Earbin
- 3. V. Kellogg*
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Mr. W. R. Gibson R. M. Klingaman Babcock & Wilcox L. L. Lawyer bec:
P. O. Box 1260 2kso5 G. P. Miller D. G. Mitchell
Lynchburg, VA,
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C., A. Nixdorf Ms. Margaret ReillyChief Div. of Reactor Rev J. P.,O'Hanlon.
iew R. N. Fr'abhakar cc:
PaDER J. L. Shirk C. W. Smyth' Fulton Bldg.
17120 Harrisburg, PA R. J. Stevens' O..J. Troffer GRC Secretary Chairman, CORB TMI-1
.s.
Chairman, PORC TMI-1 Chairman, PORC TIG l -..
.... File No... 02.0016.0001.0001.02,.
.61.0016.0003 0053 g