Early warning signs of potential servo problems:

Overcurrent Faults

This condition occurs when the servo motors exceeds the maximum current limit. This can be caused by misaligned ball screw or other mechanical problems. It can also be an early warning sign that the unit needs overall maintenance.

Corrective Action:

  1. Adjust the ball screw.
  2. Check all other mechanical movement in line after the servo motor.

Feedback Errors

These problems can be caused by the loss of feedback signal from your tachometer, encoder or resolver. This condition can cause position errors, runaway conditions and direction change.

Corrective Action:

  1. Confirm that your input commands are correct.
  2. Confirm that all electrical and cable connections are secure and clean.

Position Errors

These are caused by mechancial or feedback loop problems. Symptoms of this problem include inaccurate readings, chatter and runaway conditions.

Corrective Action:

  1. Check all mechanical movements and adjustments.
  2. Be sure all electrical connections are secure and clean.
  3. Check the amplifier’s operation

Overheating or Odor

This is a common condition in servo motors which are exposed to excessive amounts of oil or coolant spray, which can contaminate the servo’s stator, armature, or feedback unit.

Corrective Action:

  1. Move the unit to a cleaner location, or construct a shield to protect it from overspray or direct oil exposure.
  2. Periodically check and clean motor brushes.

Note: Prolonged normal use and age can cause excessive carbon buildup and worn bearings, which can also cause overheating and odor. If you have older units with this problem, schedule to have the unit rebuilt at the earliest opportunity.

Remember:

Preventative Servo Motor Maintenance:

  • Reduces down time
  • Extends unit life
  • Avoids costly replacements

Preventative maintenance or the prompt repair of servo system components is far less costly than production downtime due to equipment failure. While we at Electric Enterprise appreciate your business and will always be responsive to your needs, our prime goal is to help you keep your servo systems in top condition.