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7. BASIC BREAKER MAINTENANCE
7.1 MAINTENANCE REOUIREMENTS
TYPE H-3 AND HL-3 BREAKERS SHOULD UNDERGO SYSTEMATIC
INSPECTION, LUBRICATION AND SERVICING AT THE FOLLOWING
INTERVALS:
EVERY 1750 OPERATIONS FOR 600 AND 800 AMP BREAKERS.
EVERY 500 OPERATIONS FOR 1600 AND 2000 AMP BREAKERS.
EVERY 250 OPERATIONS FOR 3000 AMP AND ABOVE.
IN MANY INSTALLATIONS, IT MAY TAKE YEARS FOR A BREAKER
TO REACH THESE NUMBERS OF OPERATIONS. FOR THESE CASES
ANNUAL MAINTENANCE SHOULD BF PROVIDED. FOR BREAKERS
OPERATING IN VERY CLEAN ENVIRONMENTS, THIS INSPECTION
PERIOD COULD BE EXTENDED TO 2 YEARS. CONVERSELY,
BREAKERS THAT OPERATE IN VERY DUSTY, CORROSIVE OR OTHERWISE
ADVERSE ENVIRONMENTS REQUIRE INSPECTIONS AND SERVICE EVEN
MORE FREQUENTLY.
SECTION 7.2 CONTAINS A LIST OF THE MAINTENANCE TOOLS AND
SUPPLIES THAT WILL BE REQUIRED AND SUMMARY/CHECKLIST OF
THE BASIC MAINTENANCE PROCEDURES.
SECTION 7.3 DESCRIBES THE FULL PROCEDURE.
7.2 TOOLS AND CHECKLIST,
THE FOLLOWING TOOLS AND SUPPLIES WILL BE VALUABLE FOR
BASIC BREAKER MAINTENANCE:
•
AN ASSORTMENT OF SLOT AND ROBERTSON HEAD SCREWDRIVERS.
•
A WRENCH AND SOCKET SET (IN PARTICUTAR, A 7/16 INCH "DEEP"
SOCKET IS USEFUL FOR REMOVING ARC CHUTES).
•
A FEELER GAUGE.
•
AN EMERGENCY CHARGING HANDLE FOR ELECTRICALLY OPERATED
UNITS.
•
A DRAWOUT CRANK (if NONE IS AVAILABLE, A 1/2 INCH DRIVE
RATCHET AND EXTENSION CAN BE USED).
•
A SLOW-CLOSE HANDLE, DEFLECTION GAUGE, DEFLECTION AND
DIFFERENTIAL SHIMS AND A SMALL PIECE OF BEAR-TEX OR
SIMILAR ABRASIVE FIBRE MATERIAL, ALL OF WHICH ARE
AVAILABLE FROM SCHNEIDER ELECTRIC (SEE SECTION 9.1 ).
•
IF THE MECHANISM IS VERY DIRTY A CLEANING SOLVENT MAY BE
REQUIRED.
•
FOR LUBRICATION, USE CAT. NO. PJC-8311 HIGH TEMPERATURE
LUBRICATING GREASE, PART NO. 70.15.001A.002.
MAINTENANCE SUMMARY CHECK LIST
1. REMOVE OR ISOLATE BREAKER
2.
REMOVE AND INSPECT ARC CHUTES, FLASH SHIELDS, FACEPLATE
3. CLEAN BREAKER
4. CLEAN MAIN AND SECONDARY DRAWOUT CONTACTS
5. INSPECT MOULDINGS AND HARDWARE
6. INSPECT ARCING CONTACTS
7. INSPECT BRAIDS
8. INSPECT MAIN CONTACTS
9. CLEAN CLOSING MECHANISM AND DRAWOUT MECHANISMS
10. CHECK TRIP LATCH
11. CHECK CLOSE LATCH
12. LUBRICATE
13. CHECK CLOSING MECHANISM TOGGLE
14. CHECK DIFFERENTIAL
15. CHECK DEFLECTION
16. CHECK AND OPERATE CONTROL AND TRIP DEVICES
17. REASSEMBLE
18. CLEAN CRADLE MOULDINGS, CONTACTS
19. INSPECT CRADLE
20. LUBRICATE CRADLE
21. PLACE BREAKER BACK IN SERVICE
7.3 BASIC MAINTENANCE PROCEDURE
1. REMOVE OR ISOLATE BREAKER.
FOR FIXED MOUNTED BREAKERS, BEGIN BY ENSURING THAT
THE BREAKER IS ISOLATED FROM BOTH MAIN AND CONTROL POWER
SOURCES. TRIP THE BREAKER AND OPEN THE COMPARTMENT DOOR.
FOR DRAWOUT MOUNTED BREAKERS, WITHDRAW THE BREAKER
FROM THE CUBICLE (REFER TO SECTION 4.10 REGARDING DRY RUNS).
MOVE THE BREAKER TO A BENCH FOR BETTER ACCESS AND
VISIBILITY IF POSSIBLE.
BEFORE BEGINNING WORK ON THE BREAKER, CHECK THE
BOTTOM OF THE CRADLE FOR ANY HARDWARE, RETAINERS OR
BROKEN PARTS. THE SOURCE OF THESE ITEMS SHOULD BE LOCATED
AND MISSING HARDWARE OR BROKEN PARTS REPLACED.
2.
REMOVE AND INSPECT ARC CHUTES, FLASH SHIELDS, FACEPLATE
BEGIN DISASSEMBLY AND INSPECTION. AS EACH PART IS
REMOVED, WIPE IT CLEAN WITH A DRY RAG AND INSPECT FOR
CRACKS OR DISTORTION.
