The wave forms of the drives, besides the possibility of generating additional heat, can have other direct effects in the insulation system of the electric motors. All static drive uses electronic switching devices in its reversing section. The on and off switching action produces voltage and current peaks and transients that severely damage the insulation of the motor. Caused by the switching frequency, voltage peaks or high dV / dt, will have an impact on the life of the motor windings. The frequency and amplitude of these outbreaks all affect the life of the insulation and the probable form of defect.

A conservative and fair statement would be to encourage the drive manufacturer to specify to the motor manufacturer any special or differential insulation requirements, since the use of filters would over-lift the inverter. When necessary normally above 20m, the user must provide the inverter / motor manufacturer with the estimated lengths of the cables, since from this length the elevation of the line capacitance in relation to the ground causes the amplification by the reflection phenomenon, the voltage peaks , which can damage the motor insulation.