4.3
Removing faults
The following table is to be seen as a “First Aid” box. There can be a large number of different rea-
sons 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 behaviour 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.
Our applications department can give you further help with your problems.
Fault
Possible cause
Measures to remove the cause of the
fault
Motor doesn’t
rotate
— Servo-amplifier 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 to 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 temperature
— Motor thermostat 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 bearings
have been damaged
40
Servomotors AKM
Appendix
05/2006
Kollmorgen
