A Decision No One Wants To Make
Medium Voltage Variable Frequency Drives are still fairly new technology compared to many electronics. The earliest mass produced MV drive, the Robicon Harmony Series drive was first introduced in the early 1990’s and that rugged design is still in use today by many other manufactures. In fact, we still see original Robicon Harmony Series drives running all over the country!
Many of these early generation Medium Voltage VFDs are obsolete, giving managers tough decisions like:
- How long is it feasible to continue to run these old drives?
- When should I budget for replacement?
- What parts are still out there for this model?
Several Medium Voltage Drives are on their second, third, or fourth generation of controls or are obsolete completely. Just recently, Rockwell announced that the Powerflex 7000 will reach end of life by March of 2027.
EMA’s field service engineers assess the Toshiba T300MVi, Toshiba T300MV2, Siemens Perfect Harmony, Allen Bradley Powerflex 7000, TMEIC Dura-Bilt5i, Eaton SC9000, and many other medium voltage drive models on a regular basis, so we have a good understanding of whether it is worth refurbishing, upgrading, or replacing.
Why Does Capacitor Age Matter for Medium Voltage VFDs?
Electrolytic capacitors are often the component with the shortest lifespan within a medium voltage drive. Based on over 35 years of field experience, we’ve found that these capacitors typically have a usable life of approximately 7 to 10 years.
When capacitors begin to degrade, they can leak electrolytic fluid, cause voltage instability, trigger complete shutdowns, or even catch fire! If your drive is nearing or past the 10-year mark, the capacitors need close inspection. A capacitor issue can take your entire drive offline and potentially damage other components.
Capacitor reformation is also critical for drives and/or power cells that sit idle for extended periods. If a VFD has been in storage for a year or more, the capacitors may need reformation before the drive can safely return to service.
How Does Parts Availability and Lead Times Affect Your Decision?
Parts availability is an important factor in deciding whether to keep an old drive. With lead times now commonly running 50 to 65 weeks for some components, waiting for parts can cost more in downtime than completely replacing the entire drive.
For obsolete drives where new power cells and/or boards are no longer manufactured, repair or refurbishment may be your only option. EMA keeps many refurbished and tested power cells in stock from discontinued medium voltage VFDs, specifically because we’ve seen customers face this situation.
If you’re running an older Medium Voltage Drive model, ask about parts availability before a failure happens. Knowing your options in advance helps you respond faster when the drive goes down.
How Does Preventative Maintenance Extend VFD Life?
Preventative maintenance catches problems before they cause unscheduled downtime. A typical PM visit includes a full inspection of the Medium Voltage VFD inside and out. A comprehensive PM program includes things like tightening loose connections, verifying power supplies for tolerance, checking shielding and signal wiring, cleaning the drive, inspecting motor resistance, checking electrolytic capacitors, and reviewing fault history.
EMA’s trained technicians spot potential problems and recommend corrective actions before failures happen. Preventative maintenance is the most practical way to extend the life of your MV Drive; it is a proven fact.
What Role Does Remote Monitoring Play in Lifecycle Management?
Remote monitoring adds a predictive layer to VFD lifecycle management. By trending elements of VFD health over time, remote monitoring tools can identify degradation patterns before they trigger a fault.
The DriveScan remote monitoring tool continuously monitors all elements of drive health and predicts potential failures before they happen. This gives you time to plan repairs during scheduled downtime rather than scrambling after an unexpected shutdown.
Remote monitoring is especially valuable for critical applications where unscheduled downtime carries high costs. The ability to see drive health data in real time changes maintenance from reactive to predictive.
How Do You Calculate the True Cost of Downtime?
Downtime costs vary dramatically depending on your operation. A production facility, cement plant, or pipeline compressor station may face losses of hundreds of thousands of dollars per day when a critical drive is offline.
When evaluating repair versus replacement, factor in the full cost of each downtime scenario. A repair that takes two weeks while waiting for parts costs more than a replacement with a three-day lead time if your daily losses are significant.
We’ve seen situations where customers saved millions by choosing faster paths back to operation. The cheapest option on paper isn’t always the cheapest in practice when downtime costs are included.
Making the Right Decision for Your Medium Voltage VFD
A medium voltage VFD lifecycle assessment gives you the information to make smart repair or replacement decisions. The key factors are component condition, repair history, parts availability, downtime costs, and how much longer you plan to operate the drive.
Repair makes sense for isolated component failures when the rest of the drive is healthy. Replacement becomes practical when repair costs approach 50% of replacement cost, when repeated failures indicate broader degradation, or when parts are unavailable.
Do you need help assessing your medium voltage VFD or deciding between repair and replacement? Contact EMA to discuss your situation. Call us, email us, or use our chat feature. No One ANYWHERE Is Better At Drives Than We Are!
No One ANYWHERE Is Better At Drives Than We Are!