The VW3AE2901 is a fan interruption switch for Schneider Altivar floor-standing enclosures with separate air flows or the compact version. It's a control accessory that interrupts the fan supply when the inverter is not in operation, using an external 230 V AC supply. The part is listed as obsolete by the manufacturer.
What it fits and how it's used
This fan switch is designed for Altivar 61 Plus, Altivar 61 Plus-LH, Altivar 71 Plus-LH, and Altivar 71 Plus drive enclosures. The condition of use requires an external 230 V AC supply and the inverter not in operation — meaning it's a cooling-fan interlock, not a running load switch. If you're maintaining a legacy Altivar 61 or 71 floor-standing cabinet and the fan circuit needs the original interlock, this is the part that matches the original panel wiring.