Page 22
With the breaker open and springs discharged, the motor
is energized through the limit switch (LS) and the "b" con-
tact. The green indicating lamp (G) is controlled by a sep-
arate "b" contact, and when lit indicates that the breaker
is open.
Motor runs and charges the closing springs.
When the springs are fully charged, limit switch (LS)
opens
in
the motor circuit and closes
in
the spring
release coil (SR) circuit.
When the close contact (CS-C) makes, the spring
release coil (SR) is energized through the normally
closed "Y" contact, the limit switch (LS), and breaker "b"
contacts. This releases the latch holding the stop roller
on the close cam.
Springs are released to close the breaker. When the
breaker closes, the "b" contact opens to cut off spring
1.8. 33-790-11
release coil and motor, and limit switch (LS) contacts
reset.
If
the close contact (CS-C) is maintained, the "Y" relay
will be picked up by the current through the SR coil, and
will open its "Y" contact
in
the SR circuit. This allows only
one close operation until the close contact (CS-C) has
been reset. The "Y" coil has a very low drop-out voltage.
On some circuit breakers a special closing circuit may be
provided which permits the closing springs to be auto-
matically recharged immediately after the breaker is
closed instead
of
only after the breaker is opened. This is
accomplished by separating the motor and limit switch
from the "b" contact so the motor operation is indepen-
dent
of
the position
of
the breaker contacts. This arrange-
ment makes the breaker suitable for use with
instantaneous reclosing relays
or
in special operating
sequences.
2.
Trip
Shaft
3. Roller Constraining Link
16. Manual Charge
Device
23. Manual
Charge
Handle
4.
Trip
Shaft
5. Close Cam
6. Spring Release
Latch
14.
Crank
Shaft
17. Q-ank
Arm
18. Closing Spring
19.
Opening
Spring
25. Moving
Contact
Assembly
26. Insulating
Link
27. Main Drive Link
20. Closing Spring
Anchor
21.
Pole
Shaft
Fig. 20 Principal Parts
in
a Manually Charged Spring Operated Mechanism
Effective October 1998
Courtesy of NationalSwitchgear.com
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