ML18047A556
| ML18047A556 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/30/1982 |
| From: | Johnson B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8209080160 | |
| Download: ML18047A556 (2) | |
Text
consumers Power company General Offices: 1945 West Parnall Road, Jackson, Ml 49201 * (517) 788-0550 August 30, 1982 Dennis M Crutchfield, Chief Operating Reactors Branch No 5 Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOC~T 50-255 ~ LICENSE DPR PALISADES PL.ANT -
NORMAL AND DESIGN BASIS ACCIDENT (DBA) SEQUENCER PROBLEMS The purpose of this letter is to provide information regarding the discovered Normal and Design Basis Accident (DBA) seQuencer problems at the Palisades Plant and to document Consumers Power Company interim and permanent solution to the problem.
Description While reviewing the Normal and DBA seQuencer circuitry in preparation for the Auxiliary Feedwater Modification, Bechtel discovered that when either seQuencer (Normal or DBA) cycles through to the reset point (45 seconds) both seQuencers are reset.
Any subseQuent signals to initiate seQuencer operation, such as a delayed SIS, will not be acknowledged unless there has been an intervening diesel breaker opening.
If the scenario of loss of off-site power, turbine trip, reactor trip, diesel generators come on, Normal shutdown seQuencer cycles through and resets, SIS occurs, is postulated then the SIS will not initiate any automatic operation.
Interim Solution Emergency Operating Procedures (EOP) for Loss of Off-Site Power and LOCA have been changed to instruct the operator to push and hold the DBA seQuencer
.test button upon SIS or pressurizer pressure observed below 1605 psia after 45 seconds into the*event.
This action allows the DBA seQuencer to cycle and automatically load the reQuired components onto the diesel generator.
In conjunction with this procedure change a test to verify manual operation of the DBA seQuencer initiate circuit with a simulated loss of off-site power followed by a simulated SIS which occurs after the Normal shutdown seQuencer has reset is being run before Palisades is critical.
The procedure changes to EOP-2 and EOP-8.1 and the special test procedure for the discussed test are available for review at the Palisades Plant.
8209080160 820830 PDR ADOCK 05000255 P
DMCrutchfield, Chief Palisades Plant NORMAL AND DESIGN BASIS ACCIDENT (DBA) SEQUENCER PROBLEM August 30, 1982 Permanent Solution The permanent solution to this identified problem involves wiring and relay changes.
The design package will be available for your information at the Palisades Plant on September 15, 1982.
The.present schedule for installation and test of this change will be the first cold shutdown after the equipment is available on-site.
Brian D Johnson Staff Licensing Engineer CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades