12.2.7 Communication Networking
Networking
The communication network is shown in figure below. Network terminal
slaves at both ends need external resistance with a recommended value of
120 Ω, 0.25 W.
Fig. 12-2: Modbus networking
Cables may only be connected when drive is
turned off!
Recommendations on networking
● Use shielded twisted pair cable to connect RS485 links.
● Modbus cable should be adequately away from power cables (30 cm in
minimum).
● Avoid crossing of Modbus cables and power cables and use orthogonal
crossing if crossing must be used.
● The shield layer of cables should be connected to protected ground or
to equipment ground if the equipment ground has already been connec‐
ted to protected ground. Do not directly ground any point of the RS485
network.
● In no circumstance should ground cables constitute a loop.
Bosch Rexroth AG DOK-RCON02-FV*********-IB08-EN-P232/259
Rexroth Frequency Converter Fv
Communication Protocols