Mitsubishi OPC network

Hello,

I'm doing an internship at a company to finish my current education, I haven't worked with mitsubishi plcs before but it seems pretty straight forward.

Now I want to make create an OPC network so I can log data from different PLCs on the plant.
I've never had to do hardware setups like this, I have plenty of programming and software OPC experience but I've always had an existing network to start with.

Now I'm wondering what would be the easiest and cheapest way to go about this. Any input is appreciated.


CPU list:
(8) A2ASCPU-S1
(3) A2ASCPU
(1) A2ACPU-S30
(1) A3ACPUR21

It appears all cpus but one have a A1SJ71AR21 data link module attached to it. There are only two cpus that don't. I also found a network topolgie sketch, the cpus appear to be connected to the network. They appear to be connected in a ring.
Is there any way I can test this without buying OPC software before I know it'll work? Any trials or freeware?