AC/DC Servo Repair Centre

Servomotors are key components in CNC machines, robots, and other types of automated equipment in modern factories and equipment. At JJ Loughran we have recently made a significant investment in upgrading our Servo repair capabilities.

In our new facility AC/DC Servo repairs are tested both statically and dynamically to ensure proper and safe operation. Feedback encoder systems are set-up and calibrated to the correct angular position, and brakes are tested to ensure they are achieving the required holding torque.

Too often good servomotors are sent out for repair, and too often bad servomotors are put back into spare stock. Why? Because no testing program exists.


Typical Maintenance Process:
  •  Attempt to interpret drive or controller error codes
  •  Attempt to isolate problem to:
    • motor problem
    • drive problem
    • controller problem
    • cable problem
  • Start swapping spare parts until machine starts running again.

But was the problem fixed or is there still an intermittent failure that will continue to affect your up-time? Even if parts substitution isolates the problem this method can require a lot of time as motors are removed and re-installed, and you are often left with parts in various unknown states.

To ensure we continue to meet the needs of our varied customer base and avoid the pitfalls mentioned above JJ Loughran have invested in the most modern and advance servo test equipment currently on the market.


This new equipment ensures we are utilizing the most up to date methods to:
  • Reduce diagnosis effort by using a common interface for testing various Incremental Encoders, Serial Encoders, and Resolvers.
  • Simplify testing by viewing encoder counts, count rate, phase, line states, electrical angle, mechanical angle, and encoder alarm information on the same screen.
  • View resolver sine, cosine, vector levels, and calculated angle.
  • Track quality and process by logging results to disk and printing reports for customers.
  • Reduce errors and time using static alignment techniques.
  • Generate encoder memory reports and view data in human readable format (lockup angles shown in degrees, max current in amps, stall torque in Nm, max velocity in RPM, etc.)
  • Reprogram new encoders with specific memory configurations to replace non-functioning encoders.
  • Save time and avoid damaging tapered encoder shafts by using electronic alignment techniques.
  • Test run many types of motors using incremental encoder, serial encoder, or resolver feedback with one common platform.
  • Run motor with no load at various RPMs in both forward and reverse direction to check for bearing noise, vibration, or overheating.

This will reduce our customers repair costs and downtime by using in-plant testing at these critical points.

JJ Loughran’s modern servo repair and service facility has the capability to repair Servo Motors from many leading manufacturers, including Siemens, ABB, Fanuc, Lenze, Mitsubishi, Yaskawa.

If you would like to talk to us about this area of our business, please get in touch and one of our team can provide more information.

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