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FIG. 5.8.1 FACEPLATE KEY INTERLOCK
( SHOWN WITH THE
BREAKER HELD TRIP-FREE AND THE KEY FREE FOR REMOVAL).
1. LOCK
2. PLUNGER
3. MANUAL TRIP BUTTON
WHEN IT IS MORE DESIRABLE TO HAVE THE KEY INTERLOCK
MOUNTED ON THE BREAKER CUBICLE RATHER THAN ON AN
INDIVIDUAL BREAKER, A CELL KEY INTERLOCK CAN BE PROVIDED.
THIS IS A CABLE OPERATED DEVICE WHICH EMPLOYS A LOCK
MOUNTED ON BREAKER CUBICLE DOOR. A CABLE CONNECTS THE
LOCK TO A SHAFT AND LEVER ASSEMBLY MOUNTED ON THE CRADLE.
A SEPARATE CABLE SYSTEM ON THE BREAKER IS OPERATED BY THE
CRADLE LEVER TO TRIP THE BREAKER, AND HOLD IT TRIP-FREE
WHEN THE KEY HAS BEEN REMOVED FROM THE LOCK. THIS
INTERLOCK IS ONLY FUNCTIONAL WHEN THE BREAKER IS IN THE
"OPERATING" POSITION.
5.9 MECHANICAL INTERLOCK
MECHANICAL INTERLOCKS ARE AVAILABLE ON ALL H-3 BREAKER
FRAME SIZES (EXCEPT FOR 14 INCH SIZE). THEY ARE USED TO
MECHANICALLY INTERLOCK BREAKERS IN A TRANSFER SCHEME.
MECHANICAL INTERLOCKS ENSURE ONLY ONE BREAKER IS CLOSED
WHILE THE OTHER IS HELD IN A TRIP FREE POSITION.
MECHANICAL INTERLOCKS CONNECT WITH FLEXIBLE CABLE
THE CLOSING SHAFT Of ONE BREAKER TO THE TRIP SHAFT OF A
SECOND BREAKER, AND VICE VERSA. DRAWOUT BREAKERS ARE
INTERLOCKED BY CABLE CONNECTIONS BETWEEN THE TWO
CRADLES. THERE ARE NO PERMANENT CONNECTIONS BETWEEN THE
BREAKER AND MATCHING CRADLE WHEN INTERLOCKING IS
SUPPLIED, SO THE BREAKER CAN BE FREELY WITHDRAWN FROM THE
CELL. MECHANICAL INTERLOCKS ARE OPERABLE ONLY WHEN THE
BREAKER IS IN THE "OPERATING" POSITION. WHEN WITHDRAWN TO
THE "TEST" POSITION, BREAKERS ARE NOT INTERLOCKED AND CAN
BE TEST OPERATED IN THE NORMAL MANNER.
MECHANICAL INTERLOCKS ARE PRESET AT THE FACTORY AND
REOUIRE NO ADJUSTMENT.
FIG. 5.9.1 BREAKER PORTION OF MECHANICAL INTERLOCK
1.
UPPER PLUNGER CONNECTED TO CLOSING SHAFT
2.
LOWER PLUNGER CONNECTED TO TRIP SHAFT
FIG. 5.7 DOOR INTERLOCK
5.8 FACFPLATE KEY INTERLOCK AND CELL KEY INTERLOCK
A SINGLE OR DOUBLE FACEPLATE MOUNTED KEY INTERLOCK
CAN BE PROVIDED ON ALL BREAKERS. THE PLUNGER Of THE LOCK
ACTS INTERNALLY ON THE MANUAL TRIP BUTTON TO HOLD THE
BREAKER TRIP FREE AND PREVENT CLOSING WHEN THE KEY HAS
BEEN TURNED AND REMOVED. ON ELECTRICALLY OPERATED
BREAKERS, THIS ACTION ALSO OPERATES THE LATCH CHECK SWITCH
WHICH ISOLATES THE CLOSE COIL CIRCUIT.
THE FACEPLATE KEY INTERLOCK USES A TYPE
VF
LOCK WITH A
3/8 INCH PROJECTION.
