15
BY A CAM LOCATED ON THE REAR OF THE CRANK ASSEMBLY. AS
THE CRANK PASSES THROUGH TOP-DEAD-CENTRE AND THE
RATCHET WHEEL BEARING APPROACHES THE CLOSE LATCH, THE
CAM OPERATES THE LEVER AND THE SWITCH DE-ENERGIZES THE
MOTOR. THE LEVER IS RESET WHEN THE MAIN SPRING
DISCHARGES. NO ADJUSTMENT IS REQUIRED FOR THE SPRING
LIMIT SWITCH.
IT IS IDENTIFIED ON THE WIRING DIAGRAM BY THE SYMBOL
"SLS".
4.20 LATCH CHECK SWITCH (LCS)
THE LATCH CHECK SWITCH IS PROVIDED ON ELECTRICALLY
OPERATED BREAKERS TO PREVENT ANY ATTEMPTED ELECTRICAL
CLOSING UNTIL BREAKER CLOSING MECHANISM IS SET AND READY
FOR THE CLOSING OPERATION. IT IS INSTALLED TO AN ADJUSTABLE
MOUNTING PLATE ON THE OUTSIDE OF THE LEFT HAND MECHANISM
SIDE PLATE AND OPERATED BY THE TRIP SHAFT LEVER. THE SWITCH
CONTACT IS CONNECTED IN SERIES WITH THE CLOSING COIL AND IS
CLOSED ONLY WHEN THE TRIP LATCH AND LATCH ROLLER ARE
PROPERLY ENGAGED.
FOR SWITCH TO BE CLOSED THE FOLLOWING CONDITIONS MUST
BE MET.
(A)
DRAW-OUT MECHANRM GATE FULLY CLOSED.
(B)
MANUAL TRIP BUTTON RELEASED.
(C)
CLOSING SPRING FULLY-CHARGED.
IF ADDITIONAL OPTIONAL DEVICES ARE PROVIDED, THEIR
POSITIONS HAVE TO BE AS FOLLOWS:
(D) UNDERVOLTAGE TRIP DEVICE - ENERGIZED.
(E) OVERLOAD LOCKOUT MECHANISM - RESET.
(F) DOOR INTERLOCK - ENCLOSURE DOOR CLOSED.
(G) FACEPLATE KEY INTERLOCK - UNLOCKED, KEY TRAPPED.
(H) BLOWN FUSE INDICATOR - RESET.
(I) DOOR KEY INTERLOCK - UNLOCKED, KEY TRAPPED.
(K)
MECHANICAL INTERLOCK BETWEEN BREAKERS - ALTERNATE
BREAKER(S) OPEN.
ITEMS (I) & (K) ARE APPLICABLE ONLY WHEN THE BREAKER IS IN
THE "OPERATING" POSITION.
THE LATCH CHECK SWITCH IS IDENTIFIED ON WIRING DIAGRAMS
BY THE SYMBOL "LCS".
SHOULD THE BREAKER BE TRIPPED BEFORE THE CLOSE CIRCUIT
HAS BEEN DE-ENERGIZED, SPRING RECHARGING FUNCTION AND
CONSEQUENTLY BREAKER CLOSING IS BLOCKED. THE CLOSING
COIL SWITCH CONTACTS ARE IDENTIFIED ON THE WIRING DIAGRAM
BY THE SYMBOL "CC".
4.18 SPRING CHARGING MOTOR (SCM)
ALL ELECTRICALLY OPERATED BREAKERS EMPLOY A SERIES
WOUND GEAR MOTOR TO CHARGE THE CLOSING SPRING (FIG. 4.4.2,
ITEM 9). THE REDUCTION GEAR COMPARTMENT IS SEALED AND
LUBRICATED FOR LIFE AND THE ARMATURE BEARING SIMILARLY
REQUIRES NO MAINTENANCE LUBRICATION.
THE CHARGING MOTOR CUT OFF SWITCH MOUNTED ON THE
FACEPLATE PERMITS THE MOTOR TO BE DE-ENERGIZED DURING
MAINTENANCE OR INSPECTION (FIG. 3.3.2, ITEM 9). IT TAKES
APPROXIMATELY 4 SECONDS FOR THE MOTOR TO CHARGE THE
CLOSING SPRING.
TWO CHARGING MOTOR CONTROL CIRCUIT OPTIONS ARE
AVAILABLE. BREAKERS NOT REQUIRING IMMEDIATE RECLOSURE
AFTER TRIPPING ARE WIRED TO PERMIT MOTOR CHARGING
OPERATION WHEN BREAKER IS IN THE OPEN POSITION ONLY
.
THIS IS
THE STANDARD AND PREFERRED ARRANGEMENT.
BREAKERS REQUIRING A FAST TRIPPING RECLOSING FUNCTION
(AUTOMATIC CONTROL OR TRANSFER SCHEMES ETC. AS WELL AS ALL
BREAKERS EQUIPPED WITH THE ANTI PUMP RELAY) ARE WIRED TO
PERMIT THE SPRING TO BE IN THE CHARGED POS1TION AT ALL TIMES,
I.E. IMMEDIATE RECHARGE AFTER DISCHARGE REGARDLESS OF
WHETHER THE BREAKER IS IN THE OPEN OR CLOSED POSITION.
THE CHARGING MOTOR IS IDENTIFIED ON THE WIRING DIAGRAM
BY THE SYMBOL "SCM".
THE CHARGING MOTOR CUTOFF SWITCH IS IDENTIFIED BY THE
SYMBOL "IS".
4.19 SPRING LIMIT SWITCH (SLS)
ALL ELECTRICALLY OPERATED UNITS ARE EQUIPPED WITH A
LIMIT SWITCH WHICH STOPS THE MOTOR AT THE END Of THE
CHARGING STROKE (FIG. 4.4.2, ITEM 10). THE SWITCH IS MOUNTED
INSIDE THE LEFT HAND END OF THE FRONT CHANNEL (EXCEPT FOR
14" FRAME BREAKERS, WHERE IT IS LOCATED ON THE RIGHT). THE
SWITCH IS COUPLED WITH A LEVER (FIG. 4.4.2, ITEM 11) ACTUATED
