Eaton IZM97 Instruction Manual

Also see for IZM97: Operation and Maintenance Instructional Manual Instructions Installation guide

56 New generation IZM97, 99 low voltage air circuit breaker instruction manual MN013010EN February 2020 www.eaton.com.cnSection 4: Accessory devices“A”B D“B”B D“C”B D“D”B DGap =1mm Gap >1mmGap <1mmGap 0Gap 0Figure 10. Step 10Step 10: This step describes how to adjust the cables. Refer toFigure 10 on Page 5. Cable adjustment is controlled by spacernut installed at the side of cable support bracket. The small nut isinstalled at the bottom of the long rod and should not be removedafter installed. Initial adjustment must be performed with the circuitbreaker OPEN. Install the spacer nut on the center of thread por-tion of the long rod, then hand tighten it for later adjustment.Figure 10 “A” describes that the trip bar controls the opening oftwo connected circuit breakers. The swivel ring on the controllever is controlled by a return spring to attach down to one or twonuts on the lower drive lever. Adjust the large spacer nut of theright (D-position) rod back and forth until the lower nut fits on theswivel ring and rises slightly relative to the support panel. A gapcan be seen between the upper washer and the support panelslot. At this point, there is also a gap of a few millimeters betweenthe lower nut and the swivel ring on the left (B-position). Operatethe B-position long rod to close the circuit breaker. Move the leftrod down until the control nut is close to the swivel ring (Figure10 “B”). The support panel can be moved vertically and cannot berotated. Adjust the spacer nut on the B-position cable housing tomake the left cable rod up and down until the gap between theupper rod nut and the swivel ring is less than 1mm. If necessary,adjust other cable ends (C-position of other circuit breakers).Disconnect the circuit breaker.Operate the D-position long rod to close the circuit breaker. Thesupport panel should be placed upright and cannot be rotated(Figure 10 “C”). The two interlocked circuit breakers are now open.Move the left control rod down and right control rod up, and rotatethe support panel by about 60 degrees counterclockwise. Checkthe final position of the inner shaft (this will move the cables andtrip the circuit breaker). Rotate the support panel clockwise to passthrough the vertical position, keeping the cable close to the strokeend. If the tripper bar is not attached to the end position, raise theright cable and/or lower the left cable.To open and close two interlocked circuit breakers at the sametime, make sure to return the support panel to the vertical positioneach time. When one (single) of the interlocked circuit breakersis closed, it is necessary to close the auxiliary circuit breaker.When both breakers are closed, the interlock mechanism does notrespond to any closing attempts. After the function is confirmed,the adjusted cable must be fastened using a nut. Torque to 10Nm.Accurately adjust the other two circuit breakers in the same way.Each adjustment is independent of other circuit breakers. After theadjustment is completed, it can be seen that the six cables areadjusted, functional testing performs normal, and the adjustmentnuts are tightly screwed. After all operations are completed, theclosing of any two breakers will prevent the third breaker frombeing closed.Step 11: Test the interlock mechanism in the last step as shown. Totest 6-line interlock mechanism:1. Charge and close Breaker A and B. Breaker C shouldbe held in OPEN condition. Inspect the drive rod onBreaker C. The drive rod should be seen rotated to theend position (support bracket). Charge Breaker B andC and attempt to close them. Both circuit breakersshould not respond to CLOSE attempt (no noise, springdischarge or connection motion). If the circuit breakersrespond to the CLOSE attempt, refer to Step 3 to Step11. Additional adjustments may be required at cablemounting bracket2. Open Breaker A. The interlock mechanism should bereleased. Close Breaker C. Check whether the breakeris in OPEN/CLOSED position displayed by the indicator.Breaker A should now be held in the OPEN position.Repeat the above on Breaker A (drive rod positionadjustment, attempt to close)3. Open Breaker B. The interlock mechanism should bereleased. Close Breaker C. Check whether the breakeris in OPEN/CLOSED position displayed by the indicator.Breaker A and B should now be held in the OPEN posi-tion. Repeat the above on Breaker A and B (drive rodposition adjustment, attempt to close)Utilize a light amount of lubricant grease on the interlockparts to reduce friction if any parts are sticky.Table 2. Step 11 principlesSix-cable interlock assemblyTR2TR1CBAA B C0 0 01 0 00 1 00 0 11 1 00 1 11 0 1