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FIG. 8.1.1, CLOSING LINKAGE ECCENTRIC ADJUSTMENT
1.
SPRING GUIDE PIN
2.
MAIN SPRING CLAMP
3.
LOCKING PLATE
4.
ECCENTRIC
5.
TOGGLE PIN
6.
CONNECTING LINK
7.
CLOSING CASTING
8.
STOP IN MECHANISM SIDEPLATES
9.
MECHANISM SIDERATES
8.2 CLOSE LATCH ADJUSTMENT
THE FUNCTION OF THE CLOSE LATCH IS TO ARREST OR HOLD
THE RATCHET WHEEL AT A POINT 13 DEGREES PAST TOP- DEAD-
CENTRE, WITH THE SPRING FULLY CHARGED IN READINESS TO
CLOSE. THE CLOSING STROKE IS INITIATED BY RELEASE OF THE
LATCH, EITHER MANUALLY BY MEANS OF THE MECHANICAL PUSH
BUTTON IN THE FACEPLATE OR ELECTRICALLY BY MEANS OF THE CLOSE
COIL. INSUFFICIENT ENGAGEMENT OF THE LATCH MAY ALLOW THE
CLOSING STROKE TO OCCUR UPON COMPLETION OF THE CHARGING
OF THE SPRING.
TWO STOP SCREWS ARE PROVIDED FOR ADJUSTMENT. THE
UPPER SCREW CONTROLS THE ENGAGEMENT OF THE RATCHET
WHEEL BEARING WITH THE CLOSE LATCH. THE LOWER SCREW
CONTROLS THE ROTATION OF THE CLOSE LATCH TO A POINT
PERMITTING THE RATCHET WHEEL BEARING TO CLEAR THE CLOSE
LATCH THEREBY RELEASING THE CLOSING SPRING FOR DISCHARGE.
8 DETAILED MAINTENANCE INSTRUCTIONS
8.1 CLOSING LINKAGE ECCENTRIC ADJUSTMENT
DURING THE CLOSING STROKE OF THE BREAKER, THE FORCE OF
THE CLOSING SPRING IS TRANSFERRING TO THE CLOSING
MECHANISM. IT THEN MOVES THE BREAKER CONTACTS TO THE
CLOSED POSITION AND DRIVES THE CLOSING LINKAGE INTO A
TOGGLED POSITION THEREBY POSITIVELY LOCKING CONTACTS IN
CLOSED POSITION. THE TOGGLE PIN (ITEM 5) ADVANCES PAST DEAD
CENTRE, COMING TO REST AGAINST THE STOPS (ITEM 8) PROVIDED IN
THE MECHANISM SIDE PLATES. FAILURE OF THE LINKAGE TO TOGGLE
WOULD LEAVE MAIN CONTACTS HELD CLOSED BY THE DISCHARGED
CLOSING SPRING PRESSURE ONLY. AN ECCENTRIC ADJUSTMENT IS
PROVIDED TO ASSURE FULL TOGGLING OF CLOSING LINKAGE.
ECCENTRIC ADJUSTMENT IS ACCOMPLISHED BY MEANS OF AN
ECCENTRIC BOLT (ITEM 4) ACCESSIBLE FROM THE RIGHT HAND SIDE
OF THE OPERATING MECHANISM. THIS ECCENTRIC ALTERS THE
LENGTH OF THE LOWER CLOSING MECHANISM LINKAGE, THEREBY
CHANGING THE POSITION OF THE CLOSING CASTING (ITEM 7) AND
TOGGLE PIN WHEN THE MAIN SPRING IS IN THE FULLY DISCHARGED
POSITION.
TO PERFORM THIS ADJUSTMENT, IT IS CRITICAL THAT THE
CLOSING SPRING IS FULLY DISCHARGED.
TO DO THIS, APPLY PRESSURE TO THE MANUAL CHARGING
HANDLE UNTIL THE DRIVING PAWL IS FREE TO MOVE. ROTATE THE
DRIVING PAWL FREE OF THE RACHET WHEEL TEETH AND WEDGE IT
THIS WAY WITH A SCREW DRIVER OR OTHER TOOL. NOW, AGAIN
APPLY PRESSURE TO THE CHARGING HANDLE AND WITH ANOTHER
SCREWDRIVER, LIFT THE HOLDING PAWL FREE. GENTLY RELEASE
THE PRESSURE ON THE CHANGING HANDLE AND THE SPRING WILL
FULLY DISCHARGE, WITH THE CRANK ASSEMBLY GOING TO THE
BOTTOM DEAD CENTRE POSITION, AND THE SPRING GUIDE PIN
(ITEM 1) TO ITS LOWEST POINT OF TRAVEL.
NOW CHECK THE POSITION OF THE TOGGLE PIN. IT SHOULD BE
1/16 INCH, OR LESS AWAY FROM THE STOP. IF THE GAP IS MORE THAN
1/16 INCH, ADJUST THE ECCENTRIC UNTIL THE GAP IS LESS THAN 1/16".
IF THE GAP IS ALREADY LESS THAN 1/16 INCH ADJUST THE ECCENTRIC
TO FURTHER REDUCE THE GAP.
ADJUST THE ECCENTRIC BY LOOSENING THE NUT ON THE
LOCKING PLATE (ITEM 3). THEN PULL THE LOCKING PLATE OFF THE
HEXAZONAL HEAD OF THE ECCENTRIC PIN AND ROTATE THE
ECCENTRIC (USUALLY CLOCKWISE) TO REDUCE THE GAP BETWEEN
THE TOGGLE PIN AND STOP. NOW REPLACE THE LOCKING
PLATE, ROTATING THE ECCENTRIC SLIGHTLY AS REOUIRED TO
ENGAGE WITH THE LOCKING PLATE NOTCHING. RETIGHTEN THE NUT
ON THE LOCKING PLATE.
8.1 CLOSING LINKAGE ECCENTRIC ADJUSTMENT
NOW CHARGE AND CLOSE THE BREAKER AND CHECK IF THE
TOGGLE PIN IS AGAINST THE STOPS. IF IT IS NOT, REPEAT THE
ECCENTRIC ADJUSTMENT AGAIN REDUCING THE GAP BETWEEN
PIN AND STOP WITH THE MAIN SPRING FULLY DISCHARGED. THE
PROCEDURE MUST BE REPEATED UNTIL THE TOGGLE PIN RESTS
ON THE STOP IN THE CLOSED POSITION.
IF TOGGLING CANNOT BE ACHIEVED, CHECK THAT THE
CONTACT DIFFERENTIAL (SECTION 7.3.1 4) AND DEFLECTION (7.3.1 5)
