If yes, one should check the following potential sources:
- Verify that any mechanical brake that is used is releasing cleanly.
- Verify that there is no mechanical binding in the system
- Verify that the motor is wired properly and not single-phasing.
If these check out, increasing the voltage boost A8 and voltage peak functions may help. Try changing the voltage boost gradually by first increasing its value, and if that does not work then by decreasing. Then try lowering the voltage peak function and see how the machine works. Do not lower the voltage peak function to less than 90% of its nominal rating. Recall that the nominal voltage peak setting is (Incoming Line Voltage)x(full Hz of motor)/(Full motor voltage). Try increasing and decreasing the voltage boost again for best results. If the ramp down option is off (such as in a hoist operation), then one may try the pulse start option to jar the mechanism loose.
On a HOIST, sometimes the load brake will stick and cause the motor to lockup. The drive seems to ramp up and then trip out. In this case, try the pulse start option first (L31, L32), and then try the voltage boost and voltage peak functions. The proper hoist load brake functionality should always be checked prior to continued operation.