ML19274E800

Describes Evaluation & Intended Disposition of Engineered Safety Features Actuation Sys Components.Incorporates Manual Override Features Not in Exact Conformance W/Guidelines Outlined in NRC 781129 Ltr

ML19274E800
Person / Time
Site:	Calvert Cliffs
Issue date:	04/10/1979
From:	Lundvall A BALTIMORE GAS & ELECTRIC CO.
To:	Reid R Office of Nuclear Reactor Regulation
References
NUDOCS 7904240428
Download: ML19274E800 (2)

Text

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a BALTIMORE GAS AN D ELECTRIC COMPANY GAS AN D ELECTRIC DUILDING B ALTl M O R E, M ARYLA N D 212 03 ARTHUR C. LUN OVALL, J R. '

Vict Per mog as t sv m Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Attn: tb. Robert W. Reid, Chief Operating Reactors Branch #h Division of Operating Reactors

Subject:

Calvert Cliffs Nuclear Power Plant Unit Nos. 1 & 2, Docket Nos. 50-317 & 50-318 Manual Bynasses of ESFAS Sirnals

Reference:

BG&E letter dated January 12, 1979 from A. E.

Lundvall, Jr. to R. W. Reid on Containment Purging during Normal Plant Operating.

Gentlemen:

The referenced letter contained a list of equipment for which safety actuation circuits incorporated manual override features not in exact conformance with the guidelines described in the letter of R. W. Reid to A. E. Lundvall, Jr. dated November 29, 1978. This list is reneated below:

a. Switchgear Room Air-conditioning Compressor

b. Control Room Air-conditioning Compressor

c. Boric Acid Pumps

d. Diesel Generator Feeder Breakers

e. #12 & #22 Service Water Heat Exchangers Salt Water Inlet Valves

f. #12 & #22 Component Cooling Water Heat Exchangers Salt Water Inlet Valves We have completed our evaluation of these connonents, and our intentions with regard to each item are described below:

Items a & b are similar. In both cases local handsvitches exist which could block the automatic start-up of the air-conditioning compressors.

These handsvitches vill be removed.

It should be noted that these compressors are interlocked with their companion circulating air fans and will not operate if the fans are shut-off. The fans are controlled from the control room. Shutdown of the fans by the operator is visually annunciated by neans of a dedicated status light. The use of the nlant annunciator system is considered unnecessary since detection of rising temneratures in either the contro room or the switchgear room is provided to direct the operator's attent:^n to the b appropriate set of air-conditioninc system a<ctrols.

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7 90424 0 c[)tq$

High temperature in the switchgear room is visually & audibly annunciated by means of the plant annunciator system, thereby directing the operator to the switchgear room air-conditioning controls located in the control room. If temperatures rise in the control room, the operator would instinctively turn his attention to the air-conditioning controls for the control room. We intend to take no action with regard to the fan-com-pressor interlocks since ve feel that our system is an effective means of alerting the operator to the condition of the air-conditioning systems.

Item c was included in the above list, but subsequent investigation revealed that no problem exists vith these pumps. The start signal must pass through the normally closed contact of the local stop pushbutton. An incorrect model number led to the conclusion that the stop pushbutton could be locked in position. A subsequent check revealed the error. No action is required since these pumps conform to the guidelines described in your letter of November 29, 1978.

The diesel generator feeder breakers (item d) can be placed in the lock-out position by the control room operator. This action could effectively distrupt the diesel generator emergency power back-up scheme.

Such action by the operator is visually annunciated by means of a status light dedicated to monitoring the breaker control switch for the pull-to-lock position. This light is located just above the feeder breaker control switch. Additional visual indication of manual lock-out is provided by the orientation of the control switch when in the pull-to-lock position. We feel that adequate visual indication of lock-out is provided to the operator and that use of the plant annunciator is unnecessary. Therefore, we intend to make no changes to item d.

Items e & f are similar. In both cases the annunciator logic was found to be in error and vill be corrected.

For the referenced Service Water Heat Exchangers, two handsvitches control the salt water valves. One coucrols the inlet valve, and the other handsvitch controls the outlet valves. Either handsvitch in the "close" position isolates the heat exchanger, but the current annunciator logic includes intelligence from only one switch. The logic vill be changed to show the heat exchanger isolated if either handsvitch is in the "close" position and a SIAS signal is present.

For the referenced Component Cooling Heat Exchangers, two hand-switches control the salt water valves. Either handsvitch in the "close" position isolates the heat exchanger. Current annunciator logic requires both handsvitches be in the "close" position on receipt of an PAS signal in order to generate a heat exchanger isolated alarm. This vill be corrected.

A facility change re. quest has been issued to make the changes des-cribed above. Please do not hesitate to contact us if you need additional information or if you have comments on our propcsed changes.

Sincerely y s,

, . mJd A.E.Luhhvall,Jr.

Vice President - Supply ec: J. A. Biddison, Esquire G. F. Trowbridge, Esquire E. L. Conner, NRC