Capacitor Reforming: The Key to Prolonging a Drives’ Life

Capacitor Reforming: The Key to Prolonging a Drives’ Life

Many manufacturing plants, AC variable frequency drives play a vital role in ensuring operations run smoothly. They help in controlling the speed of motors and enable precise motion of devices. However, replacement has become more challenging due to parts shortages and long lead times. Many manufacturers are turning to Capacitor Reforming services to get spare or idled AC drives operational.

If sitting for a period of 12 months or more, the DC bus capacitors in AC drives can lose their electrical charge and become unstable. Capacitor reforming can bring those old capacitors back to life.  The process involves gradually charging the DC bus capacitors to restore their electrical properties and ensure that the device can store charge at its original capacity before being placed into service. The process can be done using automatic or manual reforming devices, but it’s essential to monitor the voltage levels and leakage current during the reforming process to avoid any damage.

In addition to saving cost, reforming capacitors is also an eco-friendly alternative to entirely replacing them. It is safe to say that capacitor reforming is crucial in maintaining AC drive performance but the process must be done right to guarantee the drive is ready to be placed into service.

Capacitor reforming requires specialized knowledge and equipment. It is recommended that you engage the services of qualified professionals who understand the procedure inside out.  Sure Controls experts are available to assist. Our maintenance team members have been trained on the Bonitron Capacitor Former which offers the following.


  • Reforming aging capacitors helps avoid pre-emptive replacement and can aid in preventing catastrophic failure.
  • Reforming saves the cost of purging old stock capacitors or purchasing a replacement drive.
  • Decreases maintenance time and cost.
  • Eliminate costly machine down time.

Product Highlights

  • Charges and discharges capacitors safely
  • Variable output voltage: 0 – 1000 VDC for reforming low voltage drives with a line supply of up to 690VAC.
  • Digital LCD Display
  • Portable – case on wheels
  • Operates from standard 120 VAC supply.

Industry Applications 

  • Extruders and extrusion coaters
  • Printing presses
  • Machining centers
  • Centrifuges
  • Conveyors
  • Cranes
  • Dynamometers
  • Elevators
  • Hoists

Want to learn more? Make sure to check out this quick tutorial or reach out to us at [email protected] 

Ryan is a technical support specialist at Sure Controls, prior to that he was in Sure’s service group for 13 years, starting in the shop May of 2000. He enjoys applying his technical knowledge and real world application expertise while working with the Sure team to come up with solutions to a wide range of customer opportunities. In his spare time he enjoys motorcycling, antique hunting, varmint hunting and spending time with family and friends.

Enter your keyword