Maintenance
Motor Cutoff
Switches
(For Electrically Operated Breakers)
(See
Figures 7a-7c)
Figure7a.
Position
1.
Motor in Run Position.
(Note that Figures 7a-7c are depicted as v iewed from below)
In Figure ?a, note that spring position lever ( 1) is forward,
actuating both ·switches. Motor/gear position
(2)
lever is
retracted. Motor cutoff switch (3) is closed. Application of
power at this time will cause the motor to start thereby
charging the closing springs.
Figure7b.
Position 2.
Motor not
cutoff .
While the springs are charging the motor/gear position lever
(2)
moves forward, applying pressure to the switch actuating
leaf. The spring position lever ( 1) retracts as the springs reach
full charge. The motor cutoff switch (3) is closed and the motor
is running.
Figure 7c.
Positon 3.
Motor
The springs have reached charged position. The motor/gear
lever
(2)
has been retracted by roll pins on the large gear as
the cam follower
(82,
Figure 2)
on the large spur gear has
disengaged from the wind and close cam (34,
Figure 2).
The
motor cutoff switch (3) has opened, stopping the motor and
the closing coil switch (4) has closed. Upon application of
power to the closing circuit the breaker will close. Switches
then return to No. 1 position.
Note:
In position 3 there is clearance between both levers and
the switch actuating leaf. Clearance may be minimal (ap
proximately 1/64) or up to 1 / 1 6 inch (0.4-1.6mm). It is impor
tant to completely remove pressure from the switch actuating
leaf to
be
sure that the switches are free to actuate. Adjustment
is made by carefully bending the levers as indicated by arrows
(Items 1 and 2). Do not bend the switch actuating leaf.
IMPORTANT: If the motor cutoff switch ( 3) does not open,
the motor will continue to run and the cam follower (82,
Figure 2) will re- engage wind and close cam
(34,
Figure 2,
jamming
the
entire mechanism, possibly stripping gears
in the gear motor, blowing the control fuse, or damaging
the motor. T o free a jammed mechanism
it
is necessary
to remove the gear motor.
The springs will discharge and the breaker closes when
the gear motor pinion is disengaged from the gear.
Use the manual charging mechanism or the maintenance
closing device to prevent this from happening. Move the
manual handle towards the charge position, applying
force to the closing springs, and allow the ratchet on
charging cam to support load while the motor is removed.
This prevents the closing springs from discharging when
the motor is removed.
15
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