ML19319B478
| ML19319B478 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 09/02/1977 |
| From: | Stolz J Office of Nuclear Reactor Regulation |
| To: | Roe L TOLEDO EDISON CO. |
| References | |
| NUDOCS 8001220888 | |
| Download: ML19319B478 (3) | |
Text
_ - - _ _ _ _ _ _ - _ _ _ _ _ _ _
7 _,
,4 4
ca.
LWR #1 File WPGammill RSBoyd ELD SEP 0 21977 RCDeYoung IE(3)
Docket No. 50-345 DBVassallo WHaas FJWilliams JRBuchanan JFStol2 TBAbernathy LEngle ACRS(16)
Toledo Edison Company EHylton ATTN: Mr. Lowell E. Roe RJMattson Vice President Facilities Dross Development JKnight Edison Plaza rte;esco 300 Madison Avenue HDenton Toledo, Ohio 43652 Gentlemen:
SUBJECT:
DIESEL GENERATOR LOCK 0UT - DAVIS BESSE, UNIT 1 In our review of reports submitted by licensees concerning malfunctions of diesel generators, we find that in some cases the infomation available to the control roca operator to indicate the operational status of the diesel generator may be imprecise and could lead to misinterpretation.
This can ba caused by the sharing of a single annunciator station by alarms thst indicate conditions that render a diesel generator unable to respond to an automatic emergency start signal and alarms that only indicate a warning of abnomal, but not disabling, conditions. Another cause can be the use of wording on an annunciator window that does not specifically say that a diesel generator is inoperable (i.e., unable at the time to respond to an automatic emergency start signal) when in fact it is inoperable for that purpose.
We, therefore, request that you review the alarm circuitry and diesel generator control circuitry for the diesel generators at your facility to determine how each condition that renders a diesel generator unable to respond to an autcmatic emergency start signal is alamed in the control room. These conditions include not only the trips that lock out the diesel generator start and require manual reset, but also control switch or mode switch positions that block automatic start, loss of control voltage, insufficient starting air pressure or battery voltage, etc. This review should consider all aspects of possible diesel generator operational conditions, for example test conditions and operation from local control stations. One area of particular concern is the unreset condition following a manual stop at the local station which terminates a diesel generator test prior to resetting the diesel generator controls for enabling subsequent automatic operation.
p lc ",
[f9 ovncs >
summanes >
oatu >
l
, NRC PORM 318 (946) NRCM 02 0 W u. s. eovenmassnt enmyme ornes,,,,, _,,w R 0 01220 8N
[
- c.,
s.
e, c,.
SEP 0 21877 Toledo Edison Company We request that within 4E days of your receipt of this letter that you provide the following information.
a.
all conditions that render the diesel generator incapable of responding to an automatic emergency start signal as discussed above; b.
the wording on the annunciator window in the control room that is alarmed for each of the conditions identified in a; c.
any other alarm signals that also cause the same annunciator to alam; d.
any condition that renders the diesel generator incapable of responding to an automatic energency start signal which is not alarmed in the control room; and e.
any proposed nodifications resulting from this evaluation.
Sincerely.
Original Signed by John F. Stola John F. Stolz, Chief Light Water Raactors Branch No.1 Division of Project Management ccs: See page 3 l
DPM: LWR #1 DPM:LW8_11._
o,ric a,-
._.un. d Esth 9tg' z_ _. _9/hzz
.c -- m o.m =cx myJ g,,,,__,,,,,,,,,,,,,,,,,r__
sw W
d gfV ToledoEdisonCodany,
ces: Donald H. Hauser, Esq.
The Cleveland Electric Illuminating Co:many P. O. Box 5000 Cleveland, Ohio 44101 Gerald Charnoff, Esq.
Shaw, Pittman, Potts & Trowbridge 1800 M Street, N. W.
Washington, D. C.
20036 Leslie Henry Esq.
Fuller, Seney, Henry and Hodge 300 Madison Avenue Toledo, Ohio 43604
~
s e
i i
orrecs >
eunname >
DATE M
=
- us A eowsamesent pensmaa oppicsa nave-eno.eaA NRC POEM SIS (N6) NRCM _0240,.;
. - - _ -