United States Nuclear Regulatory Commission - Protecting People and the Environment


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.                                                          



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