While a variable speed drive is often given a different name: VSD, inverter, AC inverter, variable frequency drive etc. they and soft starts all manage the supply of power to an electric motor. Most are also service items that can benefit from regular maintenance to avoid performance and efficiency reduction or eventual failure.

If the worst happens and a drive fails, then it is worth considering an emergency repair, especially for legacy equipment where a direct replacement is not available off-the-shelf. Sulzer specializes in this service and can be contacted on the details below.

Since drives contribute to the efficiency of a plant or machine by matching motor speed to demand, any degradation in the drive can affect plant productivity and OEE (overall equipment effectiveness). Any open cooling apertures can let in a significant amount of dust, fans themselves have a limited life-span and even static cooling fins can become clogged with debris; all of which lead to overheating, reduced performance and eventually a stoppage.

To avoid this happening, Sulzer recommends developing a full facility-wide inventory of drives, highlighting critical parts of the plant and starting a program of regular maintenance and health-checks. The cost of a routine service can vastly outweigh any amount of unscheduled plant downtime, so a regular check-up is very wise.

Sulzer is a leading service provider for the repair and supply of all types of inverters, whether modern or obsolete (legacy systems). Regardless of what it is called by the manufacturer, we can restore the performance and functionality of AC Drives, Variable Speed Drive (VSD) or Adjustable Speed Drive (ASD), Variable Frequency Drive (VFD) or Adjustable Frequency Drive (AFD) inverters.

We operate a no fix, no fee commitment to you on all industrial electronics service solutions. If we cannot fix your equipment you will not be charged for inspection.

Our dedicated service center in Glasgow provides a truly nationwide service to keep inverter drives of all designs in perfect working order.

Submit your enquiry below (by 14:00 GMT) and we will collect same day.

Levels of service
1. Standard (14 days)
2. Express (48 hours) *T&Cs apply

Working closely with our customers, we understand how critical your equipment is and we will do everything we can to have your processes back up and running as quickly as possible.


Don’t wait for a failure, protect your drives now…

Take advantage of a tailor-made on-site maintenance program to safeguard your equipment. We develop this with you to meet specific requirements and minimize your downtime.

  • Surveys for compatibility and obsolescence management
  • Inspection and diagnosis of equipment
  • Parameter back-up and error investigation
  • Fan inspection
  • Deep clean
  • Testing of power stage
  • Replacement of failed and consumable parts
  • Check connections and terminals 
Low voltage AC drive repairs and legacy inverter life extension options

Sulzer is ABB's first Loyalty Partner, offering workshop repair services to its large motors and generators. In addition to this, we are experienced in the repair of ABB's inverter products.

Sulzer had a proven track records in repair and maintenance of both modern and legacy ABB inverters.

Product ranges:

  • ACH-500
  • ACS-100
  • ACS-200
  • ACS-300
  • ACS-400
  • ACS-500
  • ACS-600
  • ACS-700
Allen Bradley
repairs for Rockwell, Allen Bradley drives: 1331, 1391, 1336 adjustable frequency low-voltage AC drives

Sulzer supports you with the repair and supply of new equipment, through strong connections with Rockwell Automation.

Product ranges:

  • PowerFlex 70
  • PowerFlex 700
  • PowerFlex 700s
  • PowerFlex 4
  • PowerFlex 40
  • Obsolete Bulletin 13 series
Service supports for low voltage AC drives, midi drives, and all legacy drives no longer supported by the OEM, danfoss

Through our extensive experience in many industrial sectors, Sulzer offers support for all Danfoss and Vacon VSD inverter products, including new energy efficient ranges.

Sulzer has multiple supply partners for Danfoss equipment and can offer pricing that suits your business requirements.

Product ranges:

  • VLT3000
  • VLT5000
  • VLT6000
  • VLT2800
  • VLT FC103
  • VLT FC302
  • VLT Microdrive
  • VLT FC200
  • VLT FC102
Repair of frequency inverters, discontinued and obsolete inverters and DC speed controllers, Lenze

Sulzer offers full diagnostics to troubleshoot your Lenze inverter equipment, before we recommend a repair or replacement of your drive.

Product ranges:

  • 470 Range
  • 460 Range
  • 634E
  • 8100 Series
  • 8200 Series
  • 4900 Series
  • 9300 Series
  • SMD
  • 8600 Series
Mitsubishi Electric
Optimized for energy saving and automation, variable speed drive and variable frequency drive inverter products from Mitsubishi Electric

Sulzer is a Mitsubishi Electric value partner for the repair of inverters. Our engineers have an unrivalled knowledge of Mitsubishi Electric's products and access to technical support direct from the manufacturer.

Through this partnership, Sulzer also offers competitive pricing on Mitsubishi Electric equipment.
Please contact us with your enquiry.

Full repair of Mitsubishi Electric products, with competitive pricing.

Product ranges:

  • FR F800
  • FR F700
  • FR E700
  • FR A200
  • FR A500
  • FR K400
  • FR S500
  • FR Z200
  • FR Z300
  • FR A024
Repair of inverters, variable speed drives and AC process drives for motor control system, Schneider

Sulzer has developed an extensive knowledge of Schneider, ATV and Telemechanique inverter products. Sulzer's relationship with the manufacturers allows us to offer product support and competitive pricing on both modern and obsolete legacy products.

Product ranges:

  • Telemechanique
  • Altivar series
  • ALT 30 series
  • ALT 40 series
  • ALT 50 series
  • ATV 60 series
  • ATV 70 series
Industrial automation repairs for electronics within all Siemens inverter product ranges

In addition to being an authorized repairer and partner of Siemens for motor products, Sulzer also offers repairs and refurbishments of Siemens (Loher) inverters.

Sulzer specializes in repairing or replacing all ranges, ages and sizes of Siemens' inverters.

Product ranges:

  • Simoreg 6RA range
  • Simodrive 610
  • Simodrive 611
  • Micromaster
  • Midimaster
  • Masterdrive
Repairs of WEG frequency inverter, mini drives, variable speed drives and machinery drives

Access to an extensive library of technical information for WEG inverter products, and competitive pricing through Sulzer makes our technical services the place to turn for WEG inverter repairs.

Product ranges:

  • CFW09
  • CFW11
  • CFW100
  • CFW500
Other OEMs
Optimized for energy saving and automation, variable speed drive and variable frequency drive inverter products from Mitsubishi Electric

Sulzer is not limited to working on the well-known OEM inverter brand products, the drives and brans listed above are simply those we encounter the most.

For all your inverter repair and service solutions, you can rely on our support - no matter the OEM, including:

  • Eurotherm
  • Baumuller
  • Indrmat
  • Yaskawa / Omron
  • Contraves
  • KEB
  • Toshiba
  • Parker / SSD
  • And more
Contact us