Mounting; Technical Data - ABB RS485 Installation And Startup Manual

4.3 Mounting

The Modbus adapter is specially shaped to fit the controller case and to plug into its
dedicated connectors without any other additional fixation part than just a screw.
3D view
Controller optical
transceiver

4.4 Technical data

Operating ambient temperature: -20 to +70 °C

 Number of nodes (Tx drive): 32 max
 Rx loading: receiver impedance is 1 unit load per RS485 Modbus adapter
Size of the Link: 247 stations including repeaters (31 stations and 1 repeater per

segment)
 Medium: Shielded, twisted pair RS485 cable (Belden 9841 typical)
 Maximum Bus Length: 1200 m
Topology: Multi-drop

 Serial Communication Type: Asynchronous, 2 wires half Duplex
Baud rate: 110, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600 bauds

selectable by the user (can be adjusted through the controller menus)
 Termination resistor: built in, selectable by a switch. 120 ohms resistor is needed
at both end of the line and must be switched or not depending on the location in
the Modbus network topology.
Fixing screw
57 mm
TX – RX led's
35 mm
48 mm
Controller power
supply connector
Resistor
Termination switch
Extra depth to
the controller
max. 10 mm
3D view inserted in back plate
Screwed terminal for
bus cable connection
RS485  RS485 Modbus adapter - 11