4.7 MFCHANICAL CLOSING INTERLOCKS AND PADLOCKING
BREAKERS MAY BE EQUIPPED WITH MECHANICAL DEVICES
WHICH TRIP THE BREAKER AND PREVENT THE CONTACTS FROM
BEING RECLOSED UNTIL THESE DEVICES HAVE BEEN RESET. SUCH
DEVICES ACT ON THE TRIP SHAFT OF THE BREAKER, HOLDING IT IN
THE TRIPPED POSITION. IF THE MAIN SPRING IS CHARGED AND
RELEASED, A DRY RUN WILL OCCUR BUT THE CONTACTS WILL NOT
CLOSE. THE FOLLOWING OPTIONAL DEVICES SERVE THIS FUNCTION.
THE ACTON REQUIRED TO RESET THEM IS ALSO INDICATED.
•
UNDERVOLTAGE TRIP (REF. SECTION 5.3)
-RESETS AUTOMATICALLY WHEN CONTROL POWER IS APPLIED.
•
OVERLOAD LOCKOUT (REF. SECTION 5.5)
-PUSH THE MANUAL RESET BUTTON ON FACEPLATE TO RESET
•
DOOR INTERLOCK (REF. SECTION 5.6)
-RESETS WHEN COMPARTMENT DOOR IS CLOSED
•
KEY
INTERLOCKS (REF. SECTION 5.7)
-RESETS WHEN KEY IS INSERTED AND TURNED
(KEY WILL BE TRAPPED IN THIS POSITION)
•
MECHANICAL INTERLOCKS (REF. SECTION 5.8)
-RESETS AUTOMATICALLY WHEN ALTERNATE BREAKER IS
OPENED
•
ANTI-SINGLE-PHASE DEVICE AND BLOWN FUSE INDICATOR
(REF. SECTION 4.1 1 )
-RESETS BY PUSHING INDICATORS UP AND IN TO THE LOCKED
POSITION
IN ADDITION TO THESE DEVICES, THE MANUAL TRIP BUTTON
AND DRAWOUT MECHANISM GATE ARE EQUIPPED WITH PROVISIONS
FOR PADLOCKING FOR THE PURPOSE OF LOCKING BREAKER IN OPEN
POSITION OR TO PREVENT OPERATION OF DRAWOUT MECHANISM.
THE SAFEST
METHOD TO PREVENT ACCIDENTAL BREAKER CLOSING
AND ENERGIZATION OF A BUS OR FEEDER WHICH MUST REMAIN DE-
ENERGIZED, IS TO WITHDRAW BREAKER FROM "OPERATING"
POSITION AND TO SECURE A PADLOCK THROUGH THE DRAWOUT
MECHANISM GATE PADLOCKING HASP.
FOR BREAKERS LEFT IN "OPERATING" POSITION, ACCIDENTAL
BREAKER CLOSING CAN BE PREVENTED BY LEAVING BREAKER WITH
CLOSING SPRING DISCHARGED AND ENSURING THAT IT REMAINS DIS-
CHARGED.
ELECTRICALLY OPERATED BREAKERS CAN BE PREVENTED
FROM CHARGING BY TURNING OFF MOTOR CUTOFF SWITCH, OR BY
REMOVING CONTROL POWER FUSE AND BY KEEPING THE
EMERGENCY CHARGING HANDLE REMOVED.
MANUALLY OPERATED BREAKERS WITH THE NON-REMOVABLE
CHARGING HANDLE HAVE HANDLE PADLOCKING PROVISION. A
LOCK
SECURED THROUGH HANDLE HASP PREVENTS ENGAGEMENT WITH
RATCHET WHEEL CLUTCH.
IN ADDITION A PADLOCK THROUGH THE MANUAL TRIP
BUTTON AND HASP WITH THE BUTTON DEPRESSED WILL PROVIDE
FURTHER ASSURANCE THE MANUALLY OR ELECTRICALLY OPERATED
BREAKER REMAINS OPEN.
4.5 CLOSING MANUALLY OPERATED BREAKER
TO CHARGE THE MAIN SPRING, ROTATE THE CHARGING HANDLE
COUNTER CLOCKWISE TO THE UPRIGHT POSITION AND PUSH IN TO
ENGAGE THE HANDLE WITH THE RATCHET WHEEL CLUTCH. ON
FRAME SIZES 1600 AMPS AND ABOVE, THE HANDLE IS A PULLOUT
EXTENSION TYPE FOR EASE OF OPERATION.
ROTATE THE HANDLE CLOCKWISE 180 DEGREES TO FULLY
CHARGE THE SPRING. A MULTI-TOOTH RATCHET WHEEL AND HOLDING
PAWL PREVENT RECOIL AND PERMIT SPRING CHARGING TO BE
PERFORMED IN SEVERAL SHORT STROKES IF DESIRED.
AS THE RATCHET WHEEL ROTATES THE INTERNAL CRANK TO A
POSITION 13 DEGREES PAST TOP-DEAD-CENTRE, THE CHARGING
STROKE IS STOPPED. A BEARING WITHIN THE RATCHET WHEEL COMES
TO RESET AGAIN THE CLOSE LATCH AND THE FORCE OF THE
COMPRESSED MAIN SPRING IS HELD BY THE LATCH IN READINESS TO
CLOSE.
OPERATION OF THE CLOSE LATCH BY PUSHING THE MANUAL
CLOSE BUTTON (FIG. 3.3.1, ITEM 8) IN THE FACEPLATE, RELEASES THE
SPRING ENERGY TO CLOSE THE BREAKER.
ONLY A RAPID TRIP-RECLOSE OPERATION IS REQUIRED
SHOULD THE SPRING BE RECHARCED AT THIS TIME. THIS WILL
AVOID UNNECESSARY DRY RUNS WHEN OPERATING THE
DRAWOUT MECHANISM.
4.6 CLOSING ELECTRICALLY OPERATED BREAKER
THE ELECTRICALLY OPERATED BREAKER IS EQUIPPED WITH
CHARGING MOTOR TO CHARGE THE MAIN SPRING AND A CLOSING
COIL TO RELEASE THE CLOSE LATCH.
BEGIN BY PLACING THE MOTOR ISOLATING SWITCH (FIG. 3.3.2
ITEM. 19) TO THE "ON" POSITION. THE MOTOR OPERATED OSCILLATING
LEVER WILL ROTATE THE RATCHET WHEEL UNTIL THE MAIN SPRING
IS FULLY CHARGED. AT THIS POINT A CAM BEHIND THE CRANKBOX
OPERATES THE SPRING LIMIT SWITCH LEVER AND THE SPRING LIMIT
SWITCH CUTS OFF THE MOTOR. ROTATION IS STOPPED AND THE
RATCHET WHEEL IS HELD IN POSITION BY THE CLOSE LATCH.
PUSHING THE "CLOSE" BUTTON ON THE FACEPLATE (FIG..3.3.2, ITEM 17)
ENERGIZES THE CLOSE COIL WHICH RELEASES THE CLOSE LATCH. THE
MAIN SPRING DISCHARGES AND THE MAIN CONTACTS CLOSE.
DEPENDING ON CONTROL REQUIREMENTS, INTERNAL BREAKER
WIRING WILL PROVIDE FOR EITHER CHARGE AFTER CLOSING
OR CHARGE AFTER OPENING OPERATION. (REFER To 4.18).
A REMOVABLE HANDLE IS PROVIDED TO PERMIT
EMERGENCY MANUAL CHARGING OF THE SPRING. A MECHANICAL
CLOSE BUTTON LIKE THAT ON THE MANUALLY OPERATED UNIT IS NOT
INCLUDED. EMERGENCY OPERATION OF THE CLOSE LATCH IS
ACCOMPLISHED BY INSERTION Of A PIN ATTACHED TO THE UPPER
END OF THE EMERGENCY CHARGING HANDLE, THROUGH A SMALL
APERTURE IN THE FACE PLATE (FIG. 3.3.2, ITEM. 1 7). PUSH THE PIN
GENTLY THROUGH THE APERTURE UNTIL THE BREAKER CLOSES.
