ABB PRO-33.0-TL Series - Daisy-Chaining EIA;RS-485 Transmission Lines

64 Electrical installation
 Daisy-chaining EIA/RS-485 transmission lines
Daisy-chaining is reliable and recommended when several inverters are connected to
Modbus over an EIA/RS485 transmission line.
When wiring a daisy-chain network to the inverter terminals, use suitable crimped
wire-end sleeves (with a maximum diameter of 2 mm) to join the wires together for a
reliable connection.
Data -
Termination resistor
120 ohm
Fieldbus
controller
Data +
Data -
COM
Inverter 1
COM
X2
S1:2 OFF
Inverter 2
Data +
COM
X2
S1:2 OFF
Inverter n
COM
X2
S1:2 OFF
Cable clamps
Data -
Data +
Data +
Data -
Only ground one end of the cable shield.
Do not use the cable shield as a functional ground.