The ProSoft Modbus device port can be configured for either RS-232, RS-422, or RS-485.
RS-232 allows a point-to-point connection, with 50 feet being the maximum length
RS-422 allows a multi-drop connection, with a maximum of 10 devices on the network. The maximum total distance is 4000 feet.
RS-485 allows a multi-drop connection, with a maximum of 32 devices on the network. The maximum total distance is 4000 feet.