What this AIC does on the line
The VW3A7251 is an Active Infeed Converter (AIC) — it takes three-phase 380-480 V AC and outputs a regulated DC bus (650 V DC at 400 V supply, 770 V DC at 480 V supply) for drives that need low harmonics and energy regeneration. It's a built-in unit, not an add-on box, so it lands inside the panel as part of the drive system. Rated 145 kW continuous with line current 212 A at 400 V and 160 A at 480 V. Continuous output current sits at 220 A at 400 V, 203 A at 480 V — so the 480 V leg gives you slightly less current headroom but higher voltage for the same power band.
Mounting and cooling — what fits in the cabinet
The unit measures 782 mm high by 350 mm wide by 377 mm deep — that's a tall, narrow footprint. Vertical mounting only, within ±10 degrees. Forced convection cooling moves 600 m³/h through the power circuit and 145 m³/h through the control section, so the panel needs 700 cm² of free air surface for intake and exhaust. Thermal losses run 2660 W at full load — plan the cabinet cooling around that. IP00 means no ingress protection — this is a panel-mount component, not a standalone enclosure. Pollution degree 2 per EN 61800-5-1 covers normal industrial environments with non-conductive dust.
Communication and fieldbus integration
The VW3A7251 carries a communication bridge option card with one RJ45 for Modbus and a Male SUB-D 9 on RJ45 for CANopen. Both protocols are on the same connector set — you pick the fieldbus at commissioning. The AIC talks to the drive over the DC bus, not the fieldbus, so the communication ports are for configuration and monitoring.
Lifecycle and sourcing
Standards compliance covers EN/IEC 61800-5-1 for adjustable speed drives, plus environmental classes 3K3 (temperature/humidity), 3C2 (chemical), and 3S2 (mechanical) per EN/IEC 60721-3-3. Operating altitude derates 1% per 100 m above 1000 m, up to 3000 m.