ML19332A441

Submits Info Re Diesel Generator Status Annunciation Sys Requirements Contained in IEEE Std 279-1971.Corrective Actions Required Re Disabling & Nondisabling Conditions

ML19332A441
Person / Time
Site:	Surry
Issue date:	09/08/1980
From:	Victor R LAWRENCE LIVERMORE NATIONAL LABORATORY
To:	Shemanski P Office of Nuclear Reactor Regulation
References
RV-80-09-02, RV-80-9-2, NUDOCS 8009150499
Download: ML19332A441 (3)

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] IANRENCE LIVERMORE LABORATORY September 8,1980- -

RV 80-09-02 Mr. Paul Shemanski, Operating Reactors Assessment Branch Division of Licensing

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U.S. Nuclear Regulatory Corrrnission Washington, D.C. 20555

SUBJECT:

SURRY NUCLEAR POWER PLANT, UNITS 1 AND 2 - DOCKETS 50-280 AND 50-281 DIESEL GENERATOR STATUS ANNUNCIATORS (TAC 07906 AND TAC 07907)

REFERENCE:

1. NRC letter dated March 29, 1977 to Virginia Electric and Power Company

2. Virginia Electric Power Company letter to NRC dateo May 20, 1977, NRC (Edson Case from C.M. Stallings)

3. NRC letter April 10, 1978 to Virginia Electric and Power Company, (W.L. Proffitt from A. Schwencer)

4. Virginia Electric and Power Company letter dated May 23, 1978 to NRC (A. Scnwencer from C.M. Stallings)

5. LLNL Report, UCID - 18145, " Status of Evaluation and Modifications of Diesel-Generator Status Annunciator Systems at various U.S. Nuclear Power Plants", dated October 1979 In their' letter.[Ref.-1] the NRC requested that the licensee (Virginia Electric and Power Company) provide information regarding the status annunciator system for the diesel generators at their facility. This request for information was the result of reports from licensees on incidents where diesel generators failed to responc to automatic' start signals because control switches or lockout and shutdown relays were left in shutdown condition by operators u'naware of their status. The principal reasons for this iack of awareness were:

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, ' Ll. .The. sharing of. annunciator ~ systems 1for both disabling and non-disabling alarm conditions;

2. wording on annunciator windows for disabling conditons which did not specifically say that the diesel-generator emergency start was blocked; and

3. disabling conditions which'were not annunciated in the . .

control' room.

The licensee' responded byl letter [Ref. 2],' describing'the' diesel genertor annunciator system at Surry Nuclear Power Plant, Units ~.1 and 2. A review of the licensee's' response identified several areas of concern that were transmitted to the' licensee in the NRC letter of April 10, 1978 [Ref. 3].'

1. 'The annunciator for " manual stop from local or' remote locations" has wording " EMERGENCY DIESEL N. 1 AUXULIARY. TRIP RELAY ACTUATED." This wording should be changed to more-clearly indicate tnat an automatic start is blocked..

! 2. Numerous disabling conditions (e.g., control room control switch in " EXERCISE" position, and remote control switch in

" LOCAL START" position) are alarmed on the same annunciator (i'e.,-"D/G Troubie") as non-disabling conditions. All disabling conditions should be on an annunciator separate

. from non-disabling conditions'andd clearly woraed to indicate that the D/G'is not capable of.an automatic start.

Therefore, the existing annunciator system should be modified.

The licensee in its: letter dated May 23, 1978 [Ref. 4], provided the following response.to the above concerns.

l. The annunciator window for the respective emergency generator will be changed to read " AUTO START =8 LOCKED". Concurrently the label plates on the Emergency generator control panels will be changea as follows;

a. For amber indicator light, a rea label plate reading

" AUTO START BLOCKED" will be installed.

b. For the associated push button a black label plate reading "AUT0 START UNBLOCK" will be installed.

2. From the station point of view,.a facility change to separate certain conditions.uncer "EDG DIS-ABLED" annunciator would tend to downgrade the importance of lesser. conditions that would remain under the "D/G TROUBLE" alarm. . The lesser conditions, however, have equal disabling potential.

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! It is presently station operating policy to consid'er "D/G

. TROUBLE" to be a disabling condition requiring positive

'immediate corrective action. This policy is dictated by and responds to the fact that any non-norr.nl condition of the emergency diesel generator could constitute'a Limiting Conditon for Operation as stated in station Technical Specifications. By extension, any non-normal condition must -

be. positively resolved in a timely manner.

In reviewi"g the above response, we believe that in order that the operator be porvided wsth accurate, complete and timely information pertinent to the-status of the. diesel' generators, as required by IEEE Std. 279-1971, tne following corrective actions are required of the licensee:

1. Disabling and non disabling conditions for eacn diesel generator should be separated and annunciated using separate annunciator systems.

l 2. The wording on the annunciators for disabling conditions should specifically state that the diesel generator is l

unavailable for automatic start.

3. Annunciators and alarms shall not be able to be cleared until all abnormal conditions have been corrected.

It is recommended that the licensee be informed of the above requirements and that corrective action be implemented.

! V I' Special Iss es Program l- Nuclear Systems Safety Program L

RAV:el j Copy to:

M.H. Dittmore R. Ejps l

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