PACMotion™ Rotary Servo Motors Installation and User Manual
Section 6
GFK-3169C
Mar 2021
Troubleshooting
21
Section 6:
Troubleshooting
The following table is to be seen as a
“First
Aid”
box. There can be a large number of different reasons for a
fault, depending on the particular conditions in your system. The fault causes described below are
mostly those which directly influence the motor. Peculiarities which show up in the control loop
behavior can usually be traced back to an error in the parameterization of the servo amplifier. The
documentation for the servo amplifier and the setup software provides information on these matters.
For multi-axis systems there may be further hidden reasons for faults.
Fault
Possible cause
Measures to remove the cause
of the fault
Motor doesn’t
rotate
- Servoamplifier not enabled
- Break in setpoint lead
- Motor phases in wrong sequence
- Brake not released
- Drive is mechanically blocked
- Supply ENABLE signal
- Check setpoint lead
- Correct the phase sequence
- Check brake controls
- Check mechanism
Motor runs
away
- Motor phases in wrong sequence
- Correct the phase sequence
Motor
oscillates
- Break in the shielding of the resolver
cable amplifier gain too high
- Replace resolver cable use
motor default values
Error message:
brake
- Short-circuit in the supply voltage
lead to the motor holding brake
- Faulty motor holding brake
- Remove the short-circuit
- Replace motor
Error message:
output stage
fault
- Motor cable has short-circuit or
earth short
- Motor has short-circuit or earth
short
- Replace cable
- Replace motor
Error message:
resolver
- Resolver connector is not properly
plugged in
- Break in resolver cable, cable
crushed or similar
- Check connector
- Check cables
Error message:
motor tem-
perature
- Motor thermosensor has switched
- Loose resolver connector or break in
resolver cable
- Wait until the motor has
cooled down. Then investigate
why the motor becomes so
hot.
- Check connector, replace
resolver cable if necessary
Brake does not
grip
- Required holding torque too high
- Brake faulty
- Motor shaft axially overloaded
- Check the dimensioning
- Replace motor
- Check the axial load, reduce
it. Replace motor, since the
bear- ings have been damaged
