Reliance 57C404B Communication Network Module

The Reliance Electric 57C404B Network Communications Module is an AutoMax distributed-control network card that enables two or more AutoMax controllers to exchange control and status data over a synchronous serial network. It mounts in an AutoMax Multibus rack and provides a 9-pin NETWORK connector for rack-to-rack communications and a 25-pin MONITOR RS-232 port for local status and self-test; two thumbwheel switches set the node number, with Drop 0 designated as the master and Drops 1–55 as slaves. The module operates at up to 845K baud over Belden 9259 coax and supports a distributed network length up to 3000 ft, with built-in dual-port memory for data transmission. Power is drawn from 5 V (about 2.5 A), +12 V (about 53 mA), and -12 V (about 7.5 mA); firmware revision B; weight approximately 2 lb; I/M J2-3001; compatible with AutoMax PLC/DCS 5000 systems.