A by-product of the power conversion process used in PWM AC drives is the generation of high levels of common-mode voltage. On some large motors this can couple through to the rotor shaft, and via a number of mechanisms, lead to premature bearing failure by what is now commonly termed Electrical Discharge Machining (EDM).

Combinations of shaft grounding brushes and insulated bearings have proven successful in protecting most motor installations experiencing problems. Some applications however, preclude the use of such solutions, and this is where the PDL EDM Filter offers a unique solution.

The PDL EDM Filter reduces the PWM related common-mode voltage by greater than 90%, as well as limiting dV/dt to within internationally recommended levels. The EDM Filter offers the highest level of protection available on the market today.

For more information on EDM click here.