ML18043A349

Forwards Rev Page 8-18 of Section8 of Subj Facil Fsar. Change Consists of Changing a-c Sys Supply from Motor Control Centers 1& 2 to Motor Control Centers 1&3 & Having Only 1 MCC Automatically Supplied by Emergency Generator

ML18043A349
Person / Time
Site:	Palisades
Issue date:	12/21/1978
From:	Fogg W CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	Ziemann D Office of Nuclear Reactor Regulation
References
NUDOCS 7812270146
Download: ML18043A349 (2)

Text

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• REGULATORY DOCKET FILE COPY

• General Ctflces: 212 West Michigan Avenue, Jackson, Michigan 49201

• Area Code 517 788-0550 December 21, 1978 Director, Nuclear Reactor Regulation Att: Mr Dennis L Ziemann, Chief Operating Reactors Branch No 2 US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-255 - LICE.J.1SE DPR P.t\.LI3ADES PLANT - FSAR - REVISED PAGE o-18 Attached is revised Page 8-18 of Section 8 of the Palisades FSAR. The changes are noted by a bar in the right-hand margin. The change consists of changing the a-c system supply from Motor Control Centers 1 & 2 to Motor Control Centers l & 3 and having only one MCC automatically supplied by the emergency generator.

I'his page is submitted as an update and should be inserted in your copy in place of the current page.

Wilma G Fogg Nuclear Licensing Coordinator CC: USNRC IE 7812270lt.t0

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Description and Operation S6. ;JS S a..c...p Description - The instrument a-c system is supplied by~o 3 phase transformers from Motor Control Centers 1 and 2, both o which are automatically supplied by the emergency generators up

• loss of normal and standby power. An automatic transfer swi ch is provided to transfer supply to the instrument a-c panel betw en the two power sources. Automatic transfer is initiated b an undervoltage relay on the panel.

All panel breakers are equipped with thermal gnetic trip ele-ments.. The neutral of t:he instrument s~ tem is grounded.

This system can also furnish eferred a-c buses through .a bypass regulator. ~ ,

Operation - During normal operation, is supplied to the instrument a-c bus from Motor Contra Center 1. Should the power fail from that source, the panel su ly will automatically be transferred to Motor Control Cente 2 *. When power to Motor Con-trol Center 1 is restored, the p el supply may be transferred back. Transfer in either direc on may be made manually. Bus undervoltage is annunciated the control room.

8.3.6.3 Design Analysis Each of the two transformers is sized to supply

the panel load panel bus via the bypass regiilator.

Testing - The oper tion of the transfer switch may.be checked at any time without plant operation.

8.4 power sources are designed to furnish on-site power "

shut down the plant and maintain it. in a safe shutdown under all conditions including DBA, upon loss of normal and sta by power; The emergency power sources are part of the red safeguards electrical system and are designed as Class 1

s. Reliability is assured by the two-channel concept wherein endent electrical controls and sources supply redundant a-c .

d-c engineered safeguards loads.

8.4.1 EMERGENCY GENERATORS 8.4.1.1 Design Basis The emergency generators are designed to provide a dependable on-site power source capable of starting and supplying the essen-tial loads to safely shut down the plant and maintain it in a safe shutdown condition under all conditions. The reliability of this on-site power is provided by its duplication wherein each emergency generator supplies redundant loads and each is capable of providing power to the minimum necessary safeguards.

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