Configuring The Termination - Eaton Network-M2 User Manual

Wiring the RS-485 Modbus RTU terminal
Belden 9843-24AWG or equivalent cabling (3 twisted-pair shielded 120Ω cable with ground) is recommended.

2.3.5 Configuring the termination

If the INDGW card is the last device installed in the network chain or the length of the network cable is excessive, termination
needs to be enabled.
Termination is used to match impedance of a node to the impedance of the transmission line being used. When impedances are
mismatched, the transmitted signal is not completely absorbed by the load and a portion is reflected into the transmission line.
No more than two termination points should be used in the RS-485 network.
To enable the on-board termination resistor (120Ω):
1. Locate the termination switch that is located on the top of the Modbus Network Module.
Installing the Network Management Module – 12