DB9 to RJ12 -RS485

Hello,

I am trying to read data between two PLC's over radio.
I have successfully got the two PLC's talking wired together via their built in RS485 ports.

I'm unable to get them communicating over the radio's.

Here are the Pin-Outs

RJ12 on v570


DB9 on Radios


RS485 Port Unistream



The radios are communicating OK, but are not sending any values.

The PLC's are Unitronics.

Master is a 10" Unitronics Unistream and the Slave is a Unitronics v570 PLC.

One thing that I'm not sure about is the wiring.

Does the shield/ Ground connections need to be connected for successful communications?

On the V570 End:
I have connected Pin 1 of RJ12 to Pin 2 of DB9
Pin 6 of RJ12 to Pin 3 of DB9

On Unistream End:

I have connected Pin 2 of DB9 to D+ on RS485 CPU port
Pin 3 of DB9 to D- on RS485 CPU port

Any help would be greatly appreciated
Martin

Since you have had this communicating together without the radios, the error is either the wiring or the radio setup.
I would first try to determine the mode of communication that the radios are in. (It should be RS485) It mentions in the information that the mode can be set and the default is RS232.

Hope this helps,

have you tried swapping the wires on the v570? typically b is +... but some manufacturers deviate from that for some reason. its also possible that whatever intern wrote the manual thought that b being + and a being - was illogical and changed it without consulting with someone.