Preventing Electrical Bearing Damage Caused by VFD’s


FACT: Every motor controlled by a variable frequency drive (VFD) should have bearing protection.

WHY?: Variable frequency drives induce voltage to the electric motor’s shaft that discharges through the bearings. This voltage can cause severe pitting, excessive bearing noise and eventuallybearing failure (see picture below).

IT GETS WORSE: Not only the motor’s bearings are at risk but coupled equipment like gear boxes, encoders, brake motors, etc. are also at risk of damage.Installing a bearing protection ring on your electric motor will channel that shaft voltage away from your bearings andsafelyinto ground.


Electric Motor Bearing Failure

Pitting in a electric motor’s bearing cause by shaft voltage induced by a variable frequency drive








REMEMBER: Insulating bearing housings alone does not prevent shaft current from discharging through the electric motor’s bearings and coupled equipment.

SOLUTION: Precision Electric can help you protect your bearings. Its cheaper than you think and it stops you from paying frequent electric motor repair cost. For more information on pricing on bearing damage protection and general purpose and inverter duty electric motors,

Please call toll free: 877-625-2402.

We will do everything we can to minimize your down time and maximize yourproductivity.