The VW3A46121 is a passive harmonic filter from Schneider Electric, designed to reduce current harmonics on the input side of Altivar variable speed drives. It's a line-side filter, not a motor dV/dt or sine-wave output filter — its job is to bring the drive's input current total harmonic distortion (THDI) down to levels that keep the plant within IEC 61000-3-4 and IEC 61000-3-12 limits, avoiding nuisance tripping of upstream protection and penalties from the utility. Rated for a 10 A input current and 400 V AC ±10 % at 50 Hz, it handles drives in the 4 kW to 5.5 hp range. One filter per drive is required — no sharing across multiple drives. The filter achieves 98 % efficiency, so the 131 W of thermal losses it sheds is the only heat you need to manage in the enclosure.
THDI performance by drive family
The THDI reduction depends on which drive generation it's paired with. On the older ATV61H and ATV71H (heavy-duty) and ATV71P (pump) drives at 4–5.5 kW, the filter knocks THDI down to 10 %. On the ATV61W (washdown) variant at the same power, it achieves 5 %. On current-generation Altivar drives — ATV630, ATV650, ATV930, ATV950 — wall-mounted at 4–5.5 kW, the filter delivers 5 % THDI. That's a meaningful difference: 5 % THDI keeps the installation compliant with the tighter G5/4 engineering recommendation, while 10 % still satisfies IEC 61000-3-4 for most industrial grids.
The filter connects via screw terminals accepting 0.5 to 10 mm² wire on the main power terminals and 2.5 mm² on the control/ground terminals. It carries an IP20 rating as a stand-alone component; when mounted inside an enclosure, the enclosure can achieve IP55. Operating temperature range is 5 to 45 °C without derating; above that up to 60 °C, derate current by 3 % per °C. Above 1000 m altitude, derate 5 % per additional 1000 m. Storage in original packaging is -25 to 55 °C, transport up to 65 °C.