The Schneider Electric VW3AP3721 is a communication module for the Altivar drive family, adding MD-Link, EtherNet/IP, and Modbus TCP connectivity via two RJ45 ports at 10/100 Mbps. It uses a daisy chain topology, so drives connect in a line rather than a star — useful for saving switch ports on a machine cell but means a single cable fault can drop the whole chain. An embedded HTTP server serves drive diagnostics, energy monitoring, and configuration widgets through a browser — no extra software needed for basic setup.
This card mounts inside the Altivar drive enclosure — it cannot be ordered alone; it ships only as part of a standard drive package. The two RJ45 connectors support auto-MDIX, so straight or crossover cables work without a hub. Protocol support includes EtherNet/IP adapter, Modbus TCP server, and ODVA AC Drive / CiA 402 profiles — covers most PLC integration scenarios.
Communication services and diagnostics
The module runs an SNMP agent for network monitoring, FTP for file transfer, SNTP for time sync, and RSTP for ring redundancy on Ethernet/IP networks. Four LEDs report Module Status, Network Status, and transmit/receive activity on each port — enough for a quick visual check without a laptop. Support for IPv6 addressing and half/full duplex auto-negotiation keeps it compatible with modern plant networks.
Because it ships only with a standard enclosure, a replacement order needs the drive frame code or a complete drive assembly; the card alone is not a shelf spare.