The VW3A3E402 is an encoder interface card for the Altivar drive family, accepting A, B, complement of A, and complement of B quadrature signals from an incremental encoder. It outputs a differential RS422 signal at up to 300 kHz, with a maximum cable run of 100 m between the encoder and the card. The card is powered by a 15 V DC supply (limits 15–16 V) and draws up to 175 mA. Input impedance is 1000 Ω. It includes overload and short-circuit protection on the output side.
The 300 kHz maximum operating frequency supports most standard incremental encoders used on motor shafts up to several thousand RPM with typical pulse-per-revolution counts. The 100 m cable distance limit governs installations where the encoder is mounted far from the drive cabinet — beyond that, signal degradation on the RS422 line becomes a risk. The 1000 Ω input impedance is standard for differential line receivers and matches the output stage of most industrial incremental encoders. The 15 V DC supply rail is specific to the Altivar option-bus power; verify that the drive's option slot provides this voltage before specifying.