The VW3AE0670 is a sinus filter from the Altivar 61 Plus range, designed as a protection accessory for Altivar floor-standing enclosures with separate air flows or the compact version.
What a sinus filter does in this drive system
A sinus filter sits between the drive output and the motor, smoothing the PWM waveform into a near-sine wave. That reduces motor heating, eliminates reflected-wave stress on long cable runs, and cuts audible noise from the motor laminations. On an Altivar 61 Plus floor-standing enclosure, this filter bolts into the cabinet's air-flow path — the separate air-flow design means the filter's heat gets ducted out, not recirculated over the drive electronics.