ML19276H448
| ML19276H448 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/12/1972 |
| From: | Creitz W METROPOLITAN EDISON CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML19276H447 | List: |
| References | |
| NUDOCS 7911110089 | |
| Download: ML19276H448 (2) | |
Text
e Mersopotirara Eoisora CofMAfW Subsidec,ry of General Mhc Grda:es Corc,orotoca P. o. D o x 5 42 R E ADIN o, P EN N SYLVA NI A 19603 WALT ER M. CAEITZ PatsaDENT Uni *ud States Atomic Energy Commiscion May 12, 1972 Division of Compliance, Region 1 270 Broad Street Newark, New Jersey 07101 Attention: James P. O'Reilly Director Subj ect : Three Mlle Island Nuclear Station Unit 1 - Docket No. 50-289 Gentlemen:
This letter is written in respcase to the Commission's letter of April 14, 1972 which indicated one of our activities appeared to be in nonconformance with the Three Mile Island Unit 1 FSAR. We sub=it the following information in response to the two items contained in the April 14 letter.
"1.
The FSAR statement on page 8-7 regarding color coded wiring and cabling is intended to ensure that during construct-ion and installation the specified physical separatiou is maintained for interconnecting cables routed between electrical enclosures.
The separation within electrical enclosures was controlled during design, fabrication and inspection of the equipment.
It should be noted, however, that there was no commitment to color code the channel separated wiring within the cabinets or equipment enclosure. During the early stages of equipment construction for this project, the specified flane retardant cabinet wiring was not available in different colors. As a result of this unavailability of colored wire, the main control console was wired with all one color switch-board wire.
As the project progressed, the specified flame retardant
. cabinet wire became available in the specified safeguard colors.
The Engineered Safeguards Cabinets have been wired using the appropriate safeguard color wire, thus making (visual) verifica-tion of redundant channel separation possible.
') '
~
United States Ator Energy Cennissica Attention:
Mr. J.
O'Reilly May 12, 1972 2
As a result of the Division of Conplianccs request for att easily veririable anc/or auditab'.e redundant channel separation inspection process for the nain control console, we will adequately idcatify the redundant channel wiring within the rain control console by color coding or tagging.
2.
The Engineered Safeguards Eistable cabinets nahe up
.three separate channels.
Conglete isoJation is n2intained between the input (instrenentation) and output (control) wiring of each channel (cabinet) and between the three ccUinets.
Isolated channel wiring on the input to a cabinet is carried in covered solid metal tray and conduit.
Each engineered safeguards channel output from a cabinet (there are two per cabinct) is carried in conduit, separate fron the other output of that cabinet. Adequate separation has been maintained and can be readily inspected as required. The reason that there was a lack of color coding evident during the March 9 inspect-ion is the fact that the cables, which will be properly color coded, had not yet been installed at that tine.
In addition, ne will recheck all other Ingineered Safeguard
& Reactor Protection Cabinets to ensure that they do not con-tain nultiple channels of Engineered Safeguard circuits, color coding or tagging uiring as necessary to facilitate visible inspection.
The aforenentioned action will be completed prior to fuel loading, presently scheduled for April 1973 per our letter to DRL of April 24, 1972.
Very truly /yo.urs,
,0
/f'b{Y,d W. M. Creitz President W/.C:bk