OnFilter received U.S. Patent 10,263,591 for its SF series dV/dt EMI filters for servo motors and variable frequency drives (VFDs) that block damaging high-frequency currents from destroying motor bearings.

SF series filters help to comply with IEC 60034-17/-25 by “smoothing” sharp edges of drive pulses and applying other patented technology to block ground current through the motor's bearing. This greatly reduces bearing damage prolonging life of motors and reducing maintenance cost.

Easy-to-install patented SF series filters do not require any mechanical modifications to the motor — they are small and unobtrusive.