30
TO CHECK PROPER OPERATION OF GATE INTERLOCK
MECHANISM, CHARGE CLOSING SPRING, THEN PUSH DOWN GATE. THIS
ACTION MUST RESULT IN SPRING DISCHARGE WHEN GATE IS
APPROXIMATELY HALF WAY OPEN (AND BEFORE DRAWOUT CRANK
CAN BE INSERTED IN SOCKET), BUT FAILURE OF BREAKER TO CLOSE,
I.E. A DRY-RUN SHOULD OCCUR. IT IS RECOMMENDED TO KEEP DRY
RUN OPERATIONS TO A MINIMUM AS REQUIRED TO CHECK PROPER
FUNCTION OF INTERLOCK FEATURE. TO CHECK NOW FOR GATE
INTERLOCK TRIPPING FUNCTION, CHARGE, THEN CLOSE BREAKER.
AGAIN PUSH DOWN GATE. BREAKER MUST TRIP BEFORE CRANK
HANDLE CAN BE INSERTED.
8.5 SHUNT TRIP COIL
ONE ADJUSTMENT IS PROVIDED FOR PROPER OPERATION OF THE
DEVICE AND TO CONTROL THE EXTEND OF FREE TRAVEL BETWEEN
THE PLUNGER AND THE TRIP SHAFT LEVER. BEFORE CHECKING THE
SETTING, MAKE SURE THAT THE LEFT TRIP SHAFT LEVER RESTING
AGAINST ADJUSTING SCREW. (FIG. 8.3.1, ITEM 2). A CAP OF
APPROXIMATELY 1/16 INCH SHOULD EXIST BETWEEN THE TOP OF THE
TRIP ROD (ITEM 2) AND ITS TRIP SHAFT LEVER (ITEM 1 ). IF
ADJUSTMENT IS REQUIRED, LOOSEN THE #8-32 ALLEN HEAD SET
SCREW, (ITEM 4) AND TURN THE ROD WITHIN THE PLUNGER (ITEM 3)
AS REQUIRED TO OBTAIN THE CORRECT GAP.
REMOVE THE SET SCREW AND APPLY A SMALL AMOUNT OF
BLUE LOCTITE TO IT. RE-INSERT AND TIGHTEN SET SCREW FIRMLY.
CLOSE BREAKER, THEN PUSH UP ROD SLOWLY FROM BELOW. WHEN
THE BREAKER TRIPS, THE PLUNGER SHOULD SLIGHTLY OVER-TRAVEL
BEFORE REACHING THE END OF ITS STROKE.
NOTE: WHENEVER THIS ADJUSTMENT IS MADE THE FOLLOWING
MUST BE CHECKED IF PRESENT ON THE BREAKER:
1.
DRAWOUT GATE INTERLOCK LEVER ECCENTRIC ADJUSTMENT
ON DRAWOUT BREAKERS. (SECTION 8.4).
2.
SHUNT TRIP ADJUSTMENT. (SECTION 8.5).
3.
UNDERVOLTACE TRIP STRIKER AJUSTMENT. (SECTION 8.6)
4.
LATCH CHECK SWITCH SETTING ON ELECTRICALLY OPERATED
BREAKERS. (SECTION 8.7).
8.4 DRAWOUT GATE INTERLOCK
ALL DRAWOUT BREAKERS ARE FITTED WITH A DRAWOUT GATE
INTERLOCK MECHANISM TO PREVENT CRANKING THE BREAKER IN OR
OUT OF THE CRADLE WHILE THE BREAKER IS CLOSED OR THE
CLOSING SPRING IS CHARGED. ADJUSTMENT OF THE GATE INTERLOCK
IS PERFORMED AS FOLLOWS:
BE SURE THE GATE IS FULLY CLOSED AND THE LEFT SIDE TRIP
SHAFT LEVER IS RESTING AGAINST THE ADJUSTING SCREWS. (FIG.
8.3.1, ITEM 2).
CHECK CLEARANCE BETWEEN RIGHT SIDE TRIP SHAFT LEVER
(ITEM 4) AND GATE INTERLOCK LEVER ECCENTRIC (ITEM 3) WHICH
SHOULD BE APPROXIMATELY 1 /32" (0.8 mm). IF ADJUSTMENT IS
REOUIRED, LOOSEN LOCKNUT (ITEM 1 AND ALLEN HEAD SCREW
(ITEM 2).
USING A WRENCH, ROTATE ECCENTRIC UNTIL SPECIFIED
CLEARANCE HAS BEEN OBTAINED. HOLDING THE ECCENTRIC IN
POSITION WITH WRENCH, TIGHTEN ALLEN SCREW SECURELY, AND
THE LOCKNUT.
FIG. 8.5, TRIP COIL ADJUSTMENT
1.
TRIP SHAFT LEVER
2.
TRIP ROD
3.
PLUNGER
4.
SET SCREW
8.6 UNDERVOLTAGE TRIP DEVICE (NV)
AN ADJUSTABLE STRIKER ON THE UNDERVOLTAGE TRIP
DEVICE IS PROVIDED TO CONTROL THE ENGAGEMENT OF THE
SOLENOID PLUNGER TO THE TRIP SHAFT LEVER. WITH THE
SOLENOID ENERGIZED AND THE PLUNGER SEATED, ADJUST
FIG. 8.4.1 DRAWOUT GATE INTERLOCK ADJUSTMENT
1.
LOCKNUT
2.
CAP SCREW
3.
ECCENTRIC
4.
TRIP SHAFT LEVER
