52
New generation IZM97, 99 low voltage air circuit breaker instruction manual
MN013010EN February 2020 www.eaton.com.cn
Section 4: Accessory devices
Spacer nut
Swivel ring
Sleeve
Drive end (long)
Rubber boot
Cable rod
Thread portion
Cable housing
Clearance
Short rod
Drive rod
Long rod
Driven
Drive end
Drive end
Tighten this nut before
supporting the drive end
Adjustment nut
Cable bracket
0-0.5mm clearance
after adjustment
0 to 2 mm
1 to 4 mm
3 mm
Min.
Drive rod
Drive rod
Figure 1
Circuit breaker OPEN
Figure 2
Circuit breaker CLOSE
Figure 3
Circuit breaker OPEN
Step 9: This step describes how to adjust the cables. Cable
adjustment is controlled by spacer support nut. The two rod end
nuts should not be removed. Adjustments are made with circuit
breakers open. Adjust all spacer support nuts and ensure they
are approximately centered on screw thread portion of the spacer
device, ensuring enough adjustment room in any direction. Hand
tighten all spacer nuts in this position. Perform adjustments on
drive (long rod) end of cables. After adjustment and when the
main lever is pulled, there is a clearance of 0-0.5mm between the
outer screw of the rod and the swivel ring. When with too much
clearance, adjust both spacer nuts to retract cable housing. When
with no clearance, lift the cable housing in the same way. For addi-
tional length adjustment, use the spacer nut at the other end of
the cable. Tighten the cable spacer nuts on both ends when proper
clearance is adjusted. Torque to 11-13Nm.
Step 10: Check the functionality of the control rod assembly in two
methods as shown in this step:
Check 1: With circuit breakers open, check the adjustment of
lower drive rod. The clearance between the drive rod lower right
corner and support bracket edge is 0-2mm (refer to Figure 2).
Close the circuit breaker, and rotate the drive rod by approximately
60 degrees counterclockwise. The clearance between the drive
rod lower left corner and support bracket edge is 1-4mm (refer to
Figure 2). If these clearances are out of specification, stop installa-
tion. Please consult Eaton for more assistance.
Figure 9. Step 8
Figure 10. Step 9
Figure 11. Step 10
Check 2: Check the functionality of the drive rod upper end and the
tripper bar. With the circuit breaker open, the upper left corner of
the upper drive rod must be in contact with the edge of the sup-
port bracket, and the internal shaft of the drive tripper bar should
protrude a few millimeters from the right edge of the support
bracket. With the circuit breaker closed, hold and slowly rotate the
upper drive rod counterclockwise. After rotating by approximately
30 degrees, the circuit breaker trips. If the circuit breaker does not
trip when the upper right corner of the upper drive rod is less than
3mm from the edge of the support bracket (refer to Figure 3), the
drive rod and/or tripper bar is no longer in compliance. Assembling
should stop at this point. Please consult Eaton for more assistance.
Step 11: Test the interlock mechanism
1. Charge and close Breaker A. Inspect the drive rod on Breaker B.
The drive rod should be rotated to fit closely against the support.
Charge Breaker B and attempt to close it. The circuit breaker should
not respond to close attempt (no noise, spring discharge or contact
motion). If the circuit breaker responds to the close attempt, check
Step 7 to Step 10. Additional adjustments may be required at cable
mounting bracket
2. Open Breaker A. The interlock mechanism should be released.
Close Breaker B. Verify it closed with OPEN/CLOSED mark. Breaker
A should now be held in the OPEN position. Repeat the above on
Breaker B (drive rod position, attempt to close). Now, the mechani-
cal interlock is installed and adjusted. Utilize a light amount of lubri-
cant grease on interlock parts if sticky.