We are looking to try and replace a radio link with waveshare or similar RS485 to Ethernet POE-powered devices to bridge meter data across the network. There is already a site wide managed network with switches close to the meter point and the inverter.
We have an inverter in an outbuilding. In order to get the CT data to it. The OB115-1P meter which is in the main property and has the wired CT on the main incomer. Currently the OB115 meter is wired to a OB225 transceiver and that talks to a remote OB225 Lora transceiver over a Lora PMAC link at the inverter end.
We would like to replace the radio link with the rs485 to Eth devices. Does anyone have any advice or guidance on this or has done it before?
Forget RS485 to Ethernet. Just run it as RS485 the whole way, using your Ethernet twisted pair cable. Good for runs up to 1km or so. Don’t forget the 120ohm terminating resistors at each end (and not in between) You can have multiple devices connected, daisy chain/bus style, with unique addresses to identify each one. Yes, you can run ModBus protocols over the top.
Robust. Reliable. You will get about 100metres on Ethernet, 1000metres on RS485.
You didn’t say the distance involved, but ‘outbuilding’ would indicate a relatively short distance.
It may be as simple as just unplugging your RS485 connections from the OB225 and moving them across to the other device.
Not sure why you are asking the question. Is LoRa giving you grief?
Of course you are connecting it all to HomeAssistant, the reason we are all here on these forums, right?
Yes I understand but the topology means that is not possible. The network links to the various outbuildings are PTP Unifi Wifi. So the backbone has various bridges to bring in the outbuildings.
But thanks for taking the time to reply. Also by doing this we bring in the possibility of listening to the detailed meter data the OB115 sends from mutiple hosts on the network as I understand it these devices have multi host mode and we can set the inverter as priority. HA etc.
As we have a local POE switch next to the inverter and after reading many many articles we decided to standardise on the waveshare RS485 to ETH (B) POE devices. A POC for the last couple of days on a meter in one of the outbuildings has worked perfectly with zero dropouts and continuous data into HA. Tried also running it with multi host with a small python program running continuously and both had zero dropouts with 50ms timings. So it looks like these will do as we have network everywhere and they are simple to power from POE I will report back progress as it may help others. Plan is to replace the radio link this weekend and also the monitoring link which is currently a RPI using a usb adaptor to the Inverter RS485/CAN port using a custom splitter cable for the BMS (CAN) and Solar Assistant/HA. That way we can move the RPI to the office rack and leave only waveshare devices on the network to do the RS485 stuff.
Quick update attempted to replace the usb adaptor from the solar assistant pi with a waveshare device. But solar assistance cannot see the device and there is no configuation on SA to allow you to tell it the IP of the waveshare port etc. I can talk to it directly and grab various registers. To make it work form a local python program I had to set the waveshare to modbus tcp to RTU. Then I was able to connect and retrieve data. I have no idea how to config SA to talk to it and connot find anything useful online. But proven it can be talked to. I made a custom cable with just pins 1&2 connected and then plugged that into the RS485/CAN splitter. The waveshare was set to work mode TCP Server, 9600,8,N,1 and protocol modbus tcp to rtu with multi host enabled.
Anyone have an idea how to connect SA to one of these adaptors. The connection is there but SA doesn;t see it and you can;t config the network parameters to help it!
Replying here in case it helps others. The network scanning in Solar Assitant was setup for the older solarman dongles. That uses port 8899 so simply make a cable for the Inverter RS485/Can port using pins 1&2 of a standard ethernet connector and plug that into your splitter if using one or directly into the inverter port. Wire the other end into the Wavesahre RS485 to ETH adaptor OW (RS485 B) Pin 1 O (RS485 A) pin2 and set the waveshare to the ip you want and port 8899 set working mode a sTCP Server protocol to Modbus TCP to RTU 9600,8,N,1 and save the settings then restart the device. In SA just change the connection type to network and scan. It will find the inverter and make it is a selectable connection type. Select it and connect. That it.If you also config the Multi Host settings with a 50ms collision detect. You can also connect to it directly from HA at the same time.