ML19332A444

Submits Info Re Status of Evaluation & Mods of Diesel Generator Status Annunciator Sys.Corrective Actions Required for Clear Annunciation of Disabling Conditions in Control Room.Manual Shutdown Lockout Relay Info Needed

ML19332A444
Person / Time
Site:	Quad Cities
Issue date:	09/09/1980
From:	Epps R LAWRENCE LIVERMORE NATIONAL LABORATORY
To:	Shemanski P Office of Nuclear Reactor Regulation
References
RE-80-09-08, RE-80-9-8, NUDOCS 8009150517
Download: ML19332A444 (2)

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'*M LAWPENCE LNERMORE LAECRATORY

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..orm.J September 9, 1980 -

RE 80-09-08 Mr. Paul Shemanski. 0perating Reactors Assessment Branch Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

QUAD CITIES NUCLEAR POWER STATION, UNITS 1 & 2, DOCKET N0 50-254 &-

50-265, DIESEL GENERATOR STATUS ANNUNCIATORS (TAC 07902,07903)

REFERENCES:

1. NRC letter to Commonwealth Edison Company, (CEC), dated March 29, 1977

2. CEC letter to NRC dated May 27, 1977

3. LLL Report, UCID-18145, " STATUS OF EVALUATION AND MODIFICATIONS OF DIESEL GENERATOR STATUS ANNUNCIATOR SYSTEMS AT VARIOUS U.S. NUCLEAR POWER PLANTS,' October 1979 In their letter [Ref. 1], the NRC requested that CEC provide information on-the status of annunciator system for the diesel generators at their facility.

This request for information was prompted by reports from licensees, i.e.

LER's on inciaents where diesel generators failed to. respond to automatic start signals because control switches or lockout ano shutdown relays were left in the shutdown condition by operators unaware of their status.

The principal reasons for this lack of awareness were':

1. The sharing of annunciator stations for both disabling anc ncn-disabling ala in conditions,

2. wording on annunciator windows for aisabling conditions which aid not specifically say a diesel generator emergency start was blocked,

3. disabling conditions which were not annunciated in the Control Room.

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.. . 't The licensee responded by letter [Ref. 2], describing the diesel generator annunciator. system at the Quad Cities Nuclear Power Station. A review of the licensee's' response and the LLL report [Ref. 3], has identified'several areas of concern in which the disabling conditions of the diesel generators are not clearly annunciated in the Control Room. These areas are:

1. Manual air shutoff valve placed in the closed position. .

2. Bus tie breakers between the diesel generator and the emergency bus placed in the test position.

3. Improper diesel generator governot drop setting.

4. Control switch in the "STOP" position.

5. Local selector switch in the " LOCAL" position.

The licensee also failed to providc information on the manual shutdown lockout relay.

In order to provide the operators with accurate, timely and complete information pertinent to the status of the diesel generator control system, as required by IEEE Std. 279-1971 and NRC letter of April 7, 1977 [Ref. 1], the following corrective actions are required:

1. The staff position is that if the conditions as outlined in items 1, 2 and 3 above exist from normal routine periodic testing or maintenance, they must be alarmed in the Control Room to clearly indicate that a diesel generator automatic start is blocked.

2. In items 4 and 5 above, the staff position is that this wording could be confusing. The diesel. generator automatic start and automatic start blocked annunciators must be in separate windows.

3. Are.the diesel generators provided with a manual shutdown lockout relay? If a manual shutdown lockout relay exists, an alarm must be provided which clearly indicates the ciesel generator is incapable of responding to an automatic start when the relay is not reset.

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

Special Issu . Program Nuclear Systems Safety Program RCE:el

-Copy to:

M.H. Dittmore R.A. Victor.

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