The ALC REP485 is a repeater that boosts communication signals over lengthy runs of wire. It has two bidirectional, optically isolated ports that can communicate at speeds from 1200 bps to 156 kbps. You can use the REP485 on any ALC legacy or BACnet communications using EIA-485, like ARC156 and MS/TP networks. Repeater for 156k communications.

Place a REP485 after every 31 control modules, after 2000 feet, or at each branch of a star or hybrid network. Each repeater begins a new network segment. You can wire a maximum of four REP485s in series. See Sample network configurations using REP485's (page 3) below. Refer to the Technical Handbook for more sample wiring configurations and wiring restrictions.