Schneider Electric 170NEF11021 Communication Adapter

Schneider Electric 170NEF11021 Modbus Plus communication adaptor for Modicon Momentum provides a single Modbus Plus port on Momentum I/O bases to connect to a multidrop Modbus Plus network at 1 Mbit/s with the 984 data format over twisted-pair cabling, designed to integrate seamlessly into the Momentum automation platform. The unit uses two SUB-D9 connectors—one for the primary Modbus Plus network and a second for redundancy—supporting up to 31 devices per segment and up to 63 devices across the entire segment, with a maximum cable distance of up to 5000 m when using repeaters. Power is supplied from the I/O base, and status is indicated by on-board LEDs: a green LED for module power/MB+ activity and red LEDs for network A and network B errors. The 170NEF11021 carries CE, UL and CSA certifications, reflecting its industrial-grade design for mission-critical control environments. Note that Schneider Electric lists this model as discontinued as of August 8, 2025, with end-of-service anticipated by December 31, 2029, underscoring a transition to newer Modbus Plus adapters within the Momentum family.