The VW3A3E403 is an encoder interface card for the Altivar drive range, accepting quadrature encoder signals (A, B, complement of A, complement of B, plus index/AB/A) and outputting them as open-collector signals at up to 300 kHz. The 1 kOhm input impedance and 12 V DC supply (limits 12–13 V) are sized for standard incremental encoders with complementary outputs. It provides overload and short-circuit protection on the output side.
The 300 kHz maximum operating frequency means this card handles most incremental encoders used on motor shafts up to several thousand RPM with typical 1024–5000 PPR counts — the 10000 and 5000 pulses-per-revolution values in the spec are the encoder resolutions it supports. The open-collector output stage sinks current to the drive's digital input; verify the pull-up voltage matches the drive's input threshold (typically 24 V, not the card's 12 V supply). The 500 m maximum cable distance between the encoder and the card is generous for a drive cabinet mounted near the motor, but cable capacitance at that length will limit practical frequency — derate for long runs.
Connection and wiring notes
Terminal block connections accept 0.2 mm² to 1.5 mm² (AWG 24 to AWG 15). The card draws 175 mA from the 12 V supply. For a panel-builder or commissioning engineer: the complement-of-A and complement-of-B signals are the inverted quadrature channels — if the drive expects single-ended A/B only, leave the complement terminals unwired. The open-collector output is not differential; keep the cable run from card to drive input under a few meters to avoid noise pickup.