14
User Manual
MN013016EN
Effective July 2022
Magnum PXR and Power Defense SB low
voltage power circuit breakers user manual
EATON
www.eaton.com
Figure 12. Cassette label showing DISCONNECTED, TEST, and
CONNECTED position of recessed cover
Levering circuit breaker
m
CAUTION
MAKE CERTAIN THAT THE CIRCUIT BREAKER IS FULLY INSERTED INTO ITS
COMPARTMENT BEFORE ANY ATTEMPT IS MADE TO LEVER THE CIRCUIT
BREAKER. ATTEMPTING TO LEVER THE CIRCUIT BREAKER IN BEFORE IT IS
FULLY POSITIONED INSIDE ITS COMPARTMENT CAN RESULT IN DAMAGE
TO BOTH THE CIRCUIT BREAKER AND THE COMPARTMENT.
The circuit breaker is now ready to be levered . With the circuit breaker
OPEN, the levering device access door can be raised . The levering
device is hand operated using a standard 3/8-inch square drive and
ratchet, which is not provided (
) . As long as the access
door is raised, the circuit breaker is held trip-free . Begin by
rotating the levering-in screw to the full counterclockwise
(DISCONNECT) position .
Close the compartment door and begin levering the breaker into its
different positions using a clockwise ratcheting motion . When the
circuit breaker is levered fully to the DISCONNECT or the CONNECT
position, the levering shaft hits a hard stop; do not exceed 25 ft-lb
of torque or the levering mechanism may be damaged .
The circuit
breaker can be levered with the compartment door open or
closed, but it is advisable to close the door prior to levering.
The position of the circuit breaker within its compartment is
indicated by color-coded position indicators (Red = Connect,
Yellow = Test, Green = Disconnect) (
and
) .
To remove the circuit breaker from its compartment, follow
the procedure just described using a counterclockwise
ratcheting motion .
Figure 13. Levering position indication
m
NOTICE
THE CIRCUIT BREAKER MECHANISM IS INTERLOCKED SUCH THAT
CHARGED CLOSING SPRINGS ARE AUTOMATICALLY DISCHARGED IF THE
CIRCUIT BREAKER IS LEVERED INTO OR OUT OF THE CELL. DISCHARGE
TAKES PLACE BETWEEN THE DISCONNECT AND THE TEST POSITION.
Fixed circuit breaker
The Magnum PXR and PD-SB fixed type circuit breaker differs
from the drawout version in that it has no levering device, primary
disconnects, or secondary disconnects (
) . In addition, a
fixed circuit breaker does not have a standard feature to hold the
breaker in a trip-free position . To ensure the proper sequence of
operation between two or more circuit breakers, an optional key
interlock is mounted through the front panel (
.
