ModBus RTU wiring


Thread Starter


I'm loooking on internet for wiring solution.
And I know that modbus need serial connection all components from modbus master to all slave.

But I can't find answer for that.

In house what we will do, is this wiring solution and I don't know if will be working. I have fear from interference(noise)

Here is link for scheme pic:

If it isn't practical to wire from master to slave 1 to slave 2 to slave 3 in a daisy chain, then your diagram looks OK to me.

You understand the concept that RS-485 multidrop is not a hub-and-spoke topology, it's a first-to-second-to-third-to-fourth daisy chain.

There should probably be a terminating resistor at the master and the last slave.

The wire for each A-B connection should be a 'twisted pair' wires for noise reduction. Belden 8102 cable has two twisted pairs.