Rockwell Automation 1557 MEDIUM VOLTAGE AC DRIVE - Manual (Page 262)

10-20 TROUBLESHOOTING
1557-UM050F-EN-P – June 2013
MACHINE SIDE CONVERTER AND LINE SIDE CONVERTER
There are two disc springs located top and center of the clamp pressure bar assembly (not to be confused
with the larger diameter disc springs below the pressure bar assembly ). The disc springs should just be
able to turn with finger touch (see Figure 10.2).
Figure 10.2
– Checking Clamp Force – Machine Side Converter and Line Side Converter Modules
Adjusting Clamp Pressure
If clamp forces have been checked and increasing the clamp force is required, the following procedures
should be used.
SNUBBER DIODE
To increase the clamp pressure, torque the M8 bolts in the insulation cups (13-mm wrench). Turn the first
bolt 1/4 turn and then torque the other bolt 1/4 turn, check the tabwasher. Repeat this procedure until the
tabwasher can just rotate with finger touch.
MACHINE SIDE CONVERTER AND LINE SIDE CONVERTER
To increase the clamp pressure, torque only the adjusting nut below the two indicating disc springs shown
in Figure 10.2 (21 mm open end wrench). Turn adjusting nut 1/4 turn, check the indicating disc springs.
Repeat until the indicating disc springs can just rotate with finger touch.
Never rotate
this nut
Heatsink (Simplified view)
Indicating
Disk Springs
Tension Adjusting Nut