ML18044A947
| ML18044A947 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 05/28/1980 |
| From: | Hoffman D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| TASK-08-02, TASK-8-2, TASK-RR NUDOCS 8006020272 | |
| Download: ML18044A947 (2) | |
Text
consumers Power company-* --~
General Offices: 212 West Michigan Avenue, Jackson, Michigan 49201
- Area Code 517 788-0550 May 28, 1980 Director, Nuclear Reactor Regulation Att Mr Dennis M Crutchfield, Chief Operating Projects Branch No 5 US NuclearRegulatory Commission Washingt9n, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT - MODIFICATION TO EDG ANNUNCIATOR - RESPONSE Consumers Power Company was informed of the results of the NRC's safety assessment, letter dated April 23, 1980, for the emergency diesel generator (EDG) annunciator scheme.
The results indicated that design changes to separately annunciate disabling and nondisabling alarm conditions are required.
Specifically, the NRC requested the following conditions be annunciated separately at an annunciator window with wording that clearly states the EDG automa~ic start is blocked:
- 1.
Control switc_h not in automatic.
- 2.
- 3.
Overcrank.
- 4.
Loss of d-c control relay.
- 5.
Jacket water temperature relay.
- 6.
Jacket water pressure relay.
The Palisades Plant will make the modifications to separately annunciate the following:
- 1.
Control switch not in automatic.
- 2.
- 3.
Overcrank.
- 4.
Loss of d-c control.
The annunciator windows for these* alarm conditions will clearly state that EDG automatic start is blocked.
Jacket water temperature (5) does not result in shutdown, nor starting the EDG.
The jacket water pressure (6) signal is an Booao2 oa.-=t~ ~
does it prevent indication that ~~I IO
2 the diesel has started; the signal is, therefore, used to disengage and stop the aiesel air start motors, but does not stop the diesel engine.
Since jacket water pressure is a direct function of engine speed, high jacket water pressure cannot prevent starting the diesel engine.
There are two separate starting circuits for each diesel (each containing separate jacket water pressure sensors/relays), a single failure in the jacket water pressure scheme would not prevent the diesel engine from starting.
In addition, the air start motors are alternately tested during routine surveillance of the diesels.
As a result, failure of a jacket water pressure sensor/relay would not remain undetected.
Based on the above, the plant does not consider modifications to the annlinciator scheme for jacket water temperature and jacket water pressure to be necessary.
/)~O~~-
David P Hoffman Nuclear Licensing Administrator CC JGKeppler, USNRC NRC Resident Inspector-Palisades