71 - PVD3627-August 2011
4.4. Troubleshooting
We provide hereunder a symptom list in regard with their possible cause. This is not an
exhaustive list so in case of trouble, please refer to the associated servo drive manual (the
diagnostic board indications will help you investigating).
You note that the
motor does not turn by
hand when the motor
is not connected to the
drive.
•
Check if the phases are not in short circuit.
•
Check if the rotor is externally blocked mechanically in
rotation.
You have difficulty to
start the motor or to
run it.
•
If there is a thermal protector, check it and its connection
and how it is set in the drive.
•
Check the servomotor insulation (in doubt, measure when
the motor is hot and cold.
The minimum insulation resistance measured under 500VDC
max is 50 M
Ω :
-
Between phase wire and housing,
-
Between thermal protector and housing,
-
Between resolver winding and housing.
You find that the motor
is drifting
•
Adjust the servo amplifier offset.
You notice that the
motor is racing
•
Check the speed set-point of the servo amplifier.
•
Check if you have chosen the right regulation mode
(torque, speed, position)
•
Check the resolver setting.
You notice vibrations
•
Check the resolver connection, the earth connections and
the grounding of the earth wire, the setting of the servo
amplifier speed loop and shielding.
•
Check the stability of secondary voltages.
•
Check motor fixing on its base.
•
Check the balancing.
•
Check the alignment between motor and load.
You find that the motor
is too noisy
Several possible explanations :
-
Unsatisfactory mechanical balancing,
-
Defective coupling,
-
Loosening of several pieces,
-
Poor adjustment of the servo amplifier of the
position loop : check rotation with the loop open.
-
Low drive switching frequency.
