Some drives on web-handling lines support suspended loads. These include turrets which may have a heavy roll on one side and core on the other. It also includes lifting tables used to lower finished rolls from the winder.
In the past year, I have observed runaway conditions on this type of equipment. In the cases I am familiar with, the drive did not use an encoder (sensorless or encoder less). Tuning the torque and speed regulators did not completely resolve these issues.
Some solutions that did help were:
- Set up the dynamic braking control correctly to absorb energy while lowering a load.
- Set up the mechanical brake release and engage parameters in the drive.
- Use of an encoder also helped.
I would welcome comments with other solutions to this problem.