ML20148F733

Requests That Util Review Alarm Circuitry & Diesel Generator Control Circuitry,Identifying Conditions Rendering Diesel Generators Unable to Respond to Automatic Alarms & Noting Annunciator Response for Each Condition

ML20148F733
Person / Time
Site:	Yankee Rowe
Issue date:	03/29/1977
From:	Schwencer A Office of Nuclear Reactor Regulation
To:	Groce R YANKEE ATOMIC ELECTRIC CO.
Shared Package
ML20148F739	List: ML20148F733 ML20148F755 ML20148F769
References
NUDOCS 8011060716
Download: ML20148F733 (2)

Text

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M 2 91977 f} g

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-Docket-No. 50-29 TI;. ;; q 7"..

Yankee Atomic Electric Company 5.g 1 ATTH: fir. Robert H. Groce.

Licensing Engineer --

20 Turnpike-Road- .s

.Westboro,'tiassachusetts 01581

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Gentlemen:

-RE: YANKEE-RCWE ATOMIC POWER STATION

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In our review of. reports submitted by licensees concerning malfunctions of diesel generators, we. find.that in some cases the infomation available :D to the control roon operator to indicate the operational status' of the ...

diesel generator may' be imprecise and could lead to misinterpretation. "

This can be caused by the sharing of a single annunciator station by s =;

alarms that indicate conditions that render a diesel generator unable ' = "

to respond to an automatic energency start signal and alams that only Another indicate a warning of abnomal, but not disabling, conditions. 3 cause can be the use of wording on an annunicator 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. L h <;.;

We, therefore, request that you review the alarm circuitry and diesel b .

generator control circuitry for the ciesel generators at your facility b to detornine how each condition that renders a diesel generator unable  :

to resnond to en autenatic energency start sicnal is alarmd in the  :

control room. These conditions include not only the trips that lock out the ciesel generator start cnd require nonual reset, but also +

control witch or node suitch positions that block autoestic start, p 22 loss of control voltage, insuf ficient starting air pressure or

= batwry voltage, etc. This review should consider all aspects of ,.

possible diesel generator operational conditions, for exanple test conditions and operation from local control stations. One area {

of particular concern is the unreset condition following a nanual ,.

stop at the local Station which teminates a diesel cenerator test [' lq

. prior to resetting the diesel generator controls for enabling '

subseouent autouatic operation. f p y

Please respond within 45' days of your roccipt of this letter by 9 providing the following information: /

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THJS"DOCUMENTiCONTAINS'.

POOR QUAUTYJAGESI l

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Yankee Atomic Electric Conpany N 2 S 1977 .

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(a) all conditions that renderenergency,.

the diesel generator incapable o[d g..

responding to an automatic start < signal as discu,sse ;gr:

above; >

~(b) the wording on the annunicator window in the txn control that ro/

is alarr.ed for each of the conditions identified in (t);

(c) any other alarn signals that also cause the same annunicator to alam; (d) any condition tho' renders the diesel generator incapable of [

i responding to an automatic energency start signal which is not L.

alarmed in the control roaa; and F.2=

(e) any proposed modifications resulting from this evaluation. '

Sincerely, g,

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_9tiginal signed by .=

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A. Schwencer, Chief Operating Reactors Branch #1 ~ 7 Division of Operating Reactors j cc: See next page  ;.

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DISTRIBUTION k Docket 1 NRC PDR LOCAL POR ORB #1 Reading ASchwencer 15 TVWambach l A&TKJ#r I DELD H 01&E (3) ,

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