51
User Manual
MN013016EN
Effective July 2022
Magnum PXR and Power Defense SB low
voltage power circuit breakers user manual
EATON
www.eaton.com
Primary disconnect inspection
Table 20. Pre-inspection conditions
Device
Position of poles
Mechanism
Device position in cassette
Fixed
Open
Closed
Charged
Discharged
—
—
—
—
Drawout
Open
Closed
Charged
Discharged
Connected
Test
Disconnected
Removed
Procedure
For Magnum PXR and PD-SB breakers with vertically mounted
primary disconnects:
1.
With breaker removed from cell, verify that vertical adapter nuts
and bolts are torqued to 37–43 lb-ft .
Figure 86. Primary disconnects
For all Magnum PXR and PD-SB breakers primary disconnects:
1.
Remove the primary disconnect .
2.
Inspect primary disconnect contact surfaces for indications of
plating wear, corrosion, or arcing and pitting . Replace primary
disconnect if there is evidence of any exposed copper .
3.
Inspect finger springs for broken, cracked, or misalignment
with fingers .
4.
Remove loose contaminates .
5.
Reinstall and tighten the M6 screw (refer back to
to retain the primary disconnect . Verify that the primary
disconnect is free to rotate about the screw, and return
to the home position .
6.
Be certain that the retaining screw is in the proper position and
does not deform the end plates on the primary disconnects .
Secondary disconnect inspection
Table 21. Pre-inspection conditions
Device
Position of poles
Mechanism
Device position in cassette
Fixed
Open
Closed
Charged
Discharged
—
—
—
—
Drawout
Open
Closed
Charged
Discharged
Connected
Test
Disconnected
Removed
Procedure
Breaker:
1.
Remove the breaker front cover .
2.
With breaker removed from cell, verify that the breaker
secondary disconnect pins are fully seated and locked into
position by lightly pulling on each wire individually .
ote:
N
Do not exceed 1 lb of force or damage to pin or housing may occur .
3.
Ensure all pins are straight without bends, corrosion, and do not
show evidence of arcing .
4.
Damaged pins are to be replaced . Refer to renewal parts catalog .
m
WARNING
REMOVE ALL POWER TO THE CASSETTE SECONDARY PINS.
Cassette:
1.
On the cassette side of the secondary disconnect, ensure
all sockets are fully seated and locked into position by lightly
pressing on each socket .
2.
Visually inspect each socket for evidence of arcing, corrosion,
or foreign objects .
3.
Damaged sockets are to be replaced . Refer to renewal parts
catalog
4.
Ensure that socket housings are free to move to allow
self-aligning with the breaker side secondary housing
.
Figure 87. Breaker secondary
Figure 88. Cassette secondary
Vertical adapter bolt
Primary disconnect bolt
