EMA Inc.

EMA Inc.EMA regularly provides preventive maintenance on nearly all brands of Medium Voltage AC drives, Low Voltage Drives and DC drives. We have vast experience performing preventative and predictive maintenance on the following Medium Voltage VFDs: Toshiba T300MVi/MV2, Siemens/Robicon Perfect Harmony Series, Allen Bradley Powerflex 7000, TMEIC Dura-Bilt 5i and MVe2, and Eaton SC9000.

Our trained technicians will spot potential problems and recommend corrective actions before a failure causes unscheduled and costly downtime.

If you’d like to see an example of a typical preventative maintenance report, please contact us.

What’s Involved In Routine Preventive Maintenance?

Clean the drive:

Dust and other foreign materials can create cooling problems, hide damaged components, cause corrosion, and cause arcing and other damage.

Evaluate Fault History:

By examining the fault history of the drive, our technicians will get a better understanding past problems and be better informed to help resolve those problems. 


Check motor resistance and connections:

Motors often exhibit changes in resistance prior to failing.


Verify all power connections:

Power connections can loosen over time due to vibration and heat-related expansion and contraction. Loose power connections can cause blown fuses, tripped breakers, damage to terminal strips, insulation failure, and ground faults.


Verify power supplies for tolerance:

Power supplies can drift out of tolerance due to electronic problems such as faulty electrolytic caps. These will eventually cause a complete shutdown.


Observe relevant waveforms for best operation:

We typically look at the supplies, output waveforms, reference signals and feedback signals. This often uncovers otherwise hidden problems.


Shielding properly terminated and Verify signal wiring:

Improper shielding can cause the erratic and intermittent behavior of drive equipment, and loose signal wiring is a primary cause of drive equipment downtime.