ML20071B052
| ML20071B052 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 02/07/1983 |
| From: | Williams F NEBRASKA PUBLIC POWER DISTRICT |
| To: | Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| Shared Package | |
| ML20071B044 | List: |
| References | |
| LQA8300084, NUDOCS 8302250309 | |
| Download: ML20071B052 (2) | |
Text
, -.
r-GENERAL OFFICE Nebraska Public Power District
" " "?s!30*$'f"^!s^""
LQA8300084 February 7, 1983
] g_(O' j () 4 l\\
FEB 91983 L1l i> U
'V Mr. John T. Collins Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76011
Subject:
Cooper Nuclear Station Agastat Relays
Reference:
(1) Letter, F. E. Williams, NPPD to J. T. Collins, NRC, dated September 28, 1982, LQA8200189
Dear Mr. Collins:
Reference (1) discussed the preliminary results of the investigation and evaluation of the use of commercial grade Agastat relays in safety-related locations at the Cooper Nuclear Stotion (CNS). This initial review identified approximately 26 relays installed in safety-related systems which required further engineering evaluation to assure that continued operation would not jeopardize the health and safety of the pdolic.
The subject engineering evaluation of existing Agastat relays has been completed.
In general, there are three generations of /.gastat relays installed at CNS; the 2400 series (pre 1968), the 7000 series (1968-1978) and the nuclear grade "E" series (post 1978).
Both 2400 and 7000 series relays were used in construction contracts and both 7000 and "E" series relays have been used in design changes since construction. Of 140 such relays identified at Cooper Nuclear Station, 49 are considered " essential".
The series identification of these 49 " essential" relays is as follows:
2400 Series - 9 relays 7000 Series - 16 relays "E" Series - 24 relays As a result of this evaluation NPPD has decided to replace the " essential" 2400 series and 7000 series relays with nuclear grade "E" series relays as soon as possible.
Replacement relays have been placed on order.
Selected relays will be replaced upon receipt of material with the remainder scheduled for replacement during the May 1983 outage.
Pending relay replacement continued plant operation is justified based on plant / system redundancy and the very low probability of a seismic
- ( )[
8302250309 830222 PDR ADOCK 05000298 G
PDR l.
. s
./
- Mr. John T. Collins
. February 7, 1983 Page.2 event.
In addition, there have been very few, if any, malfunctions of Agastat relays at CNS.
If you have any questions or comments on this subject, please contact me.
Sincerely, 4
Fred E. Williams Quality Assurance Manager FEW: GAT:cmk i
e 9
d f
yy-y re e g,
v-,-,- - - - - -- - - - -,. - -,,,
y-e,i
~,
e--am---. - - ~,-
7-.- - -
,.,----n.
-e.,
,,m.
-m-,
- - -.--, - - - - - -,-, - --.----