Ethernet over RS-485? Can it be done? Indeed it can be done, and there might even be commercial products that can convert between the physical media standards.
20180820/https://en.wikipedia.org/wiki/RS-485
20180820/DuckDuckGo ethernet over rs-485
Yeah, people who don’t know what they are talking about here. If they use a distance of over 100 meters, they need to decrease the data rate, as noted in the excellent Robotiq article.
20180820/https://www.cnet.com/forums/discussions/ethernet-over-rs485-634218/
20180820/https://blog.robotiq.com/what-is-rs485-communication-protocol
Images are broken in latest webpage, look at Internet archive copy to see images.
20180820/https://web.archive.org/web/20160104170447/http://blog.robotiq.com:80/what-is-rs485-communication-protocol
20180820/https://www.amazon.com/ethernet-rs485/s?page=1&rh=i%3Aaps%2Ck%3Aethernet%20to%20rs485
20180820/https://www.amazon.com/Ethernet-Max-921-6Kbps-Interface-Converter-Adapter/dp/B071XP4PY6/ref=sr_1_4?ie=UTF8&qid=1534788631&sr=8-4&keywords=ethernet+to+rs485