ICM-MODBUS Particle Counter wiring

[TC_Magic]

PXI 8431

We have a ICM-Modbus Particle Counter from www.mpfiltri.co.uk.

It has 2 wires, *Data+" "and Data-", but we know there is 2 way communication.

Shoud we connect the TXD+ and the RXD+ to Data+?

[K C]

Hi,

The PXI8431 has RS-422/485 ports. To use a RS-422 port as a RS-485 you connect the Data+ to the both + connections like you said. Same for the Data-.

In MAX you should set the 8431 port to 'RS-485 auto'

Kees

[K C]

and sometimes there are manufacturers that call there RS-485 connection otherwise like: B+ and A- to make it more confusing.

So you can try to swap the two wires if it is not working. Also don't forget the terminators and (especially if one or both ports are galvanic isolated) the 0V connection.

Kees