Creating an RS-485 Network Bridge

[@jockinafrock]

I have used these to get RS-485 SCADA signals across an Ethernet network, all the way from Edinburgh to Birmingham. I work for a global telecoms company. The SCADA link is for monitoring environmental alarms at a remote site.

[@drtweak87]

Damn where was this a year ago when I needed something like this. Not sure what all you have tested it on, but on an access control brand called PTI for self storage, they are RS485 for all their keypads and alarm boxes. Their wireless modules are $$$$$. This client had existing networking for cameras. I couldn't find anything was was more of a bridge but designed for be a virtual com port. With how cheap they are might have to buy a pair and test them!

[@dc95811]

2 videos back I used them to remote a 2way radio head at 115,200 baud and they worked great the first time I hooked them up. The company didn't make it easy to find, but I found the pdf write up to put them in bridge mode. Idk how they make a profit.

[@OzByDrone]

Interested in seeing this on the wire within wireshark to help debug some rs485 stuff.

[@dj_paultuk7052]

I do this all the time with Lantronix UDS10's.

[@Elemino]

What is RS-485 used for? Is it anything like RS-232?

[@dc95811]

It is just like RS-232 but can be ran down a lot longer pair of wires because the voltages are not referenced to ground but to each other making it more noise resistant.

[@wedgeantilles1678]

ok i have a scenario where i need to have tcp/ip devices talk and send about 1Mb over an rs485 network. can that be done w these? Basically lose the network switch and connect one rs485 adapter to internet, connect rs485 between both devices and a pc on the other end. will it work?

[@dc95811]

I know exactly what you are talking about. A reverse bridge. I had the same idea for rs-232. The answer is no. I will put it simply, those devices can only communicate on the ethernet with other devices like itself, that does rs485 stuff. It would have nothing to say to any of your other tcp/ip devices and would ignore them.

[@wedgeantilles1678]

@@dc95811 Thanks for responding to my inquiry. Ill just give you the whole story. im trying to connect 2 ham repeaters together over a 900mhz data radio link that is rs485 only. the ham gear is tcp/ip. My prospective thought is that at each location id have a eth to rs485 converter. ham repeater with eth card connected to converter > rs485 to data radio > data gets sent over the air to the other 485 data radio > converter back to eth then to the ham repeater.

[@dc95811]

@@wedgeantilles1678 dialup modems using rs232 to rs485 converters. PC's at both ends, bridged ethernet port at remote end to a little switch, giving those devices access to the dialup modem, and a way back home to the LAN.

[@wedgeantilles1678]

@@dc95811Thats brilliant! Im gonna try that. Its gonna be a complex hodge podge but thats what ham is all about and itll sure fit the budget.

[@charleskhenry]

Could you drop a link into the description of the modules you used. Thanks!

[@dc95811]

Above thanks!

[@charleskhenry]

@@dc95811 Keep up the content. You did a good job on this one.