The Schneider Electric VW3A3E411 is an encoder interface card for the Altivar drive family. It accepts RS422 differential encoder signals (A, B, Z plus complements) and outputs the same format for encoder emulation, so the drive can replicate the encoder signal to a PLC or motion controller. The card handles up to 300 kHz, which covers most incremental encoders up to 10,000 pulses per revolution at moderate speeds.
The ratio is programmable: 1, 1/2, 1/4, 1/8, 1/16, 1/32, or 1/64. That means the output frequency can be divided down from the input — useful when the downstream controller cannot handle the full encoder rate, or when you need a scaled position feedback for a different axis. The input impedance is 440 Ω, which is standard for RS422 receivers and ensures proper termination on a differential line. Supply voltage is selectable: 5 V (5.0–5.5 V) or 15 V (15–16 V), matching common encoder supply rails. The card draws up to 0.2 A from the drive's internal supply, so check the drive's auxiliary power budget before adding multiple option cards. Short-circuit and overload protection are built in on the output side, which protects the card and the drive if a field wire shorts or the encoder cable is damaged. The maximum cable distance between the card and the encoder is 50 m at the rated supply — enough for most machine-mounted encoders but not for remote shaft monitoring across a plant.
The card mounts inside the Altivar drive option slot. Wiring is via spring-cage terminals accepting 0.2 to 1.5 mm² (AWG 24 to 15). The differential outputs are RS422 compliant, so they drive long cables (up to 50 m) without signal degradation, provided the cable is twisted-pair and terminated at the receiver.