Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
LICENSEE: COOPER ENERGY SERVICES
SITE: COOPER ENERGY SERVICES EN NUMBER:34708
DOCKET: EVENT DATE: 08-28-98
RX TYPE: EVENT TIME: 00:00
VENDORS: NOTIFY DATE: 08-28-98
EMERGENCY CLASS: N/A REGION: 1 STATE: PA TIME: 15:43
OPS OFFICER: BOB STRANSKY
10 CFR SECTION: CCCC 21.21 UNSPECIFIED PARAGRAPH
10 CFR PART 21 REPORT REGARDING ENTERPRISE DSR-4 AND DSRV-4
EMERGENCY DIESEL GENERATOR STARTING AIR PRESSURE SWITCHES
"THE FUNCTION OF THE STARTING AIR PRESSURE SWITCHES (PS-3B & 4B)
IS TO DE-ENERGIZE THE STARTING AIR SOLENOID VALVES ON THE
CONDITION THAT THE STANDBY DIESEL GENERATOR DOES NOT START WITH
AN EMERGENCY START SIGNAL. THE PRESSURE SWITCHES ARE SET FOR A
LOW PRESSURE LIMIT (TYPICALLY 150 PSI FALLING) TO ENSURE A
SUFFICIENT VOLUME OF AIR IN THE STARTING AIR RECEIVERS TO ALLOW
THE OPERATOR TO HAVE MORE THAN TWO ADDITIONAL MANUAL STARTS. WHEN
THE STANDBY DIESEL GENERATOR IS RUNNING IN AN EMERGENCY MODE AND
A NON-ESSENTIAL PNEUMATIC SHUTDOWN SENSOR TRIPS, STARTING AIR
PRESSURE IS VENTED FROM THE SYSTEM. AT THE LOW LIMIT SETTING THE
STARTING AIR PRESSURE SWITCHES WILL OPEN, DEENERGIZING THE
DEACTIVATE SHUTDOWN SOLENOID VALVE. WITH THE SOLENOID VALVE
DE-ENERGIZED, THE SHUTDOWN CIRCUIT WILL RECOGNIZE ANY
NON-ESSENTIAL SHUTDOWN SIGNAL RESULTING IN A SHUTDOWN OF THE
STANDBY DIESEL GENERATOR.
"TO CORRECT THIS CONDITION THE PRESSURE SWITCHES NEED TO BE
REWIRED TO A DIFFERENT LOCATION."
AFFECTED UTILITIES: ALL ENTERPRISE EDGs EXCEPT THOSE AT PLANT
VOGTLE.
