waveshare Ethernet Industrial Serial Server RS485 to RJ45 Ethernet Module, TCP/IP to Serial, Support Rail-Mount/Modbus Gateway, TCP Server/TCP Client/UDP Mode/UDP Multicast Multi Communication Modes

Perfect solution for my home automation need. This interface only took a few minutes to get programmed and communicating properly and has been holding up great for several months in a garage.

Immediately there's one problem, and I don't understand why Chinese manufacturers do this: The IP address is set statically at 192.168.1.254 rather than using DHCP. Even when set to DHCP, it does not properly pull DNS servers from DHCP and has it set statically to 192.168.1.3, which doesn't matter much because it doesn't need DNS, but still. It's such a weird default that the rest of the world does not use. Ethernet devices should start with DHCP, and they should always pull DNS from DHCP unless set statically after DHCP config. After that, everything is excellent. Just beware that the ground plug on top of this is not the same as the negative of the input voltage. Make sure your modbus sensor/device is powered the same way this is powered. Honestly, a great device and exactly what I needed for testing a modbus TCP implementation.

I'm working on a personal project with the Modbus functionality. The device I'm working on was tested with the Serial to RS485 dongle and working fine. I added the RS485 to the RJ45 Ethernet Module (waveshare), enabled the Modbus TCP to RTU mode, set the device address, and sent the following command: `modbus 192.168.6.35:2020 -s213 h@13` The "waveshare" is able to transmit data to my device, and my device successfully processes the command responding with the correct Modbus response: [23:50:09][D][uart_debug:114]: <<< D5:03:00:0D:00:01:07:DD [23:50:09][D][uart_debug:114]: >>> D5:03:02:08:27:CF:8C However, the "waveshare" device, seems, to either have a defective RX port or can not transmit the response back. I tried modbus_cli and ModbusMechanics. Both fail with the "waveshare" device but work with the USB458 dongle. *Correction*: Looks like it was a subtle bug with the particular Modbus library on my device and/or the device(s). Even though the USB dongle works correctly, another device from a different vendor behaves the same way. Setting 2 stop bits helped. I assume the "waveshare" device would work perfectly with this setup. Sorry for the initial negative review.

For a RS485 to ethernet net device, these devices work very well for that application. My issue is that you cannot restrict the TCP server to listen for a single TCP session. So if these are used on the internet behind a firewall, multiple internet users can connect to the TCP IP port at the same time and disrupt the data stream by injecting unwanted data. If the manufacturer could add a setting to limit the number of simultaneous connections to one, these RS485 devices would work pretty well but alas they don't currently have this capability exposed on the built in web configuration page. Also there is not device status web page to show you connections and the amout of data transmitted. These RS485 devices do not come with an AC adapter nor any instructions. The default IP address is printed on the label on the device. You need to use a web browser to configure the device. There is only a single web page provided to set up the device. I ended up acquiring a different RS485 device that looked similar but addressed all the shortcomings that this device had. If you need an RS485 to ethernet adapter to use on your local LAN and not over the internet, this device works very well.

IT does the job, but it doesn't support speeds such as other converters.