Schneider Electric 140NOM21100 Industrial Relay

Schneider Electric's 140NOM21100, sold as the MB+-HEAD 1 CH DIO head-end adaptor for the Modicon Quantum PLC, provides a single Modbus+ RS-485 communication channel over twisted-pair copper and uses a Sub-D 9-pin interface to connect the head-end I/O to the Quantum backplane. It is specified as 1 Modbus channel over RS-485 with twisted-pair wiring and a bus current consumption of approximately 780 mA, enabling a compact, one-channel link between the Quantum controller and a remote digital I/O head-end. Lifecycle notices vary by region: Spain lists discontinuation on July 25, 2023 and out-of-service on July 25, 2025, while the UK catalog notes an end-of-life target of December 31, 2030, illustrating Schneider's regional lifecycle management for NOM family components. For future deployments, Schneider Electric highlights a replacement path to the Modicon M580 family, with the BMENOC0301 Ethernet-capable module as the suggested upgrade for this reference.