Westek is launching Schaffner’s FN 5040/3045 output filters for variable speed drives.
The basic topology of the Schaffner filters is a series of line inductors and filtering capacitors arranged in either star form or delta-wired, depending on the exact variation chosen as well as current rating.
The filters are suitable for inverters with switching frequency selection ranges from 2 kHz to 4 kHz.
The Schaffner FN 5040/5045 filters provide a smooth sinusoidal set of line voltages so that irrespective of cable length to a large degree, voltage build-up due to pulse reflection is avoided.
For PWM frequencies of 2 kHz, cable length can be as high as 2000 metres.
These filters are suitable for line voltages to 500 volts, motor frequencies to 70 Hz, and to 200 Hz with suitable derating (50% at 200 Hz).
Rated motor current filters are available from 4.5 amps to 1200 amps.
The Schaffner FN 5040 series has an IP rating of IP00 and the FN 5045 series, a rating of IP20.