I'm new to this please be gentle, RS485 query

Hi all, please be nice, I’m struggling to find help to get some RS485 data transmitted
In the long run I want to monitor all my electric usage against my PV generation
My first issue before I even start is adding a battery system, I know you are all saying “this is not the right place” but hold on my battery system need to be with my PV array at the bottom of my garden, but the smart meter Autometers DDSD285 using RS485 is in my house. So here is my issue I need to get the RS485 traffic between the 2 places, I do have fibre and can transfer the data over IP, how hard can that be? I thought…
Well I bought myself IP two RS485 converters to act as client server 1-port RS485 to Ethernet Converters | Ethernet to RS485 Converters | RS485 to TCP IP Converters
Just plug them in and it will just work? Nope, I’m stuck!
Well the 2 devices talk to each other but no traffic passes, maybe I have the settings wrong? It is set both sides to be 9600 8 bit parity even stop bits 1 client is with the meter server is with my battery system.
Have I gone down a mad route or have I just got it spectacularly wrong in setup?
Thanks for any help in advance…

Welcome, Adrian, to the OEM forum.

First, a disclaimer: I don’t know anything about these units - I’ve never used one or anything like it. And I’m not a networking expert either. But I’m writing as a retired applications and system engineer.

There’s something missing from that sentence, or there are too many verbs. I take it the RS485 is facing “outwards”, and the Ethernet connects the two modules. Don’t forget I only know what you’ve written about your set-up.

Is one giving the other the correct IP address - or are they competing? i.e. does each one know who’s in charge of the Ethernet link? How do you know the two talk to each other?

If you use something else on the Ethernet side, can you talk to the RS485 equipment at either end separately?

How do you know what both ends use on the RS485 side? Have you got the A & B legs the right way round? Do you need terminations? Or have you double-terminated?

If I’ve got my basic assumption right, why did you need these? Why can’t you use RS485 all the way to the garden?

I would agree with Robert on all the above. The app engineers in my work get through quite a lot of these types of units (not this particular one) to connect up some of our older products, but the reasons for it are really financially motivated by customers to reduce expensive leased lines in their infrastructure.

In practise I would be surprised if you couldn’t get away with just going RS485, but that’s making lots of assumptions on all the things Robert has pointed out - I’d suspect mis-wiring A/B or mis-configuration (both trying to get a DHCP address maybe by default) etc.

There is a link on there page you sent - I’m not sure if I’m allowed to link to it directly but it shows you can set them in bridge mode. It sounds like that’s what you are aiming for but perhaps I’ve misread your situation? To try it, follow your own link, scroll down to FAQ and there’s one called “Can Two USR-TCP232-304 Devices Work in Bridge Mode?”

Might help, might not - good luck!

Thanks all for your wisdom and showing the fact I wrote it late at night without re reading what I had written, as you rightly point out some of it was utter rubbish LOL

Anyway, I worked through the problem with a clear train of thought today after ignoring it for a few days, what I realised was the meter was not just going be sending traffic, my solar charging system needed to request it, swopped client and servers sides and hey presto data transmission!, to say I’m pleased is an understatement.

Just to clarify, I sadly don’t have a spare CAT5 cable in the conduit running down my garden, just power and 8 core fibre, and I didn’t leave a pull string in either, I really didn’t think that through!

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I thought the probability was that it might be something relatively simple that was causing the problem.

Next time, put a string loop in - so that you can use it more than once.