Waveshare RS232/485 to WiFi/ETH
Connect an RS-485 inverter or battery to Epilykos with a Waveshare serial server.
Modbus
Read an inverter or charge controller over RS-485 or Modbus-TCP.
RS232 serial
Read inverters that talk over a serial cable in their own protocol.
The Waveshare RS232/485 TO WIFI ETH (B) is a small serial server. It connects the RS-485 (or RS232) port on an inverter or battery to your network over Wi-Fi or Ethernet. Epilykos then reads it as a Modbus source over TCP. The PoE version of the same module works the same way.
What you need
- The module, powered with 6–36 V DC (DC jack or screw terminals).
- Two wires from the module's RS-485 A and B terminals to the inverter or BMS. Connect A to A and B to B.
- A device that speaks Modbus RTU on its RS-485 port, and a matching profile from Supported hardware.
- A computer or phone, to set up the module once.
Set up the module
Connect to it. Power the module and join its Wi-Fi network, called Waveshare_xxxx (the last four
digits of its MAC address). It's open by default. Then open http://10.10.100.254 in a browser and
log in with admin / admin. If that address doesn't load, try 10.10.100.222.
If the module doesn't answer, hold the RELOAD button for more than 5 seconds after power-up to restore the factory settings.
Put it on your network. Choose one:
- Ethernet: the port is off by default. Enable it on the Ethernet setting page as a LAN port.
- Wi-Fi: on the wireless terminal (STA) page, enter your router's name and password.
The module can't use STA and Ethernet at the same time. Give it a fixed IP or a DHCP reservation on your router so Epilykos can always find it.
Match the serial settings. On the serial port and network settings page, set the baud rate, data bits, parity and stop bits to what your inverter or BMS expects; check its manual. The module's default of 57600, 8, 1, none is rarely right. 9600 and 115200 are common.
Choose the TCP settings. Set the network protocol to TCP, mode Server, port 8899 (the default). Leave TCP connection password verification off. When it's on, a client has to send the web password first, and Epilykos doesn't.
Leave Modbus polling off. It's a separate feature of the module, and Epilykos does its own polling.
Choose a work mode. Both of these work, and each needs a different Gateway type in Epilykos:
| Work mode on the module | Gateway type in Epilykos |
|---|---|
| Transparent transmission (the default) | Transparent gateway (RTU over TCP) |
ModbusTCP<=>ModbusRTU (AT+TMODE=modbus) | Gateway converts to Modbus-TCP |
Start with transparent mode. The module passes the Modbus RTU frames through unchanged, so there is less to go wrong. Waveshare's manual doesn't say how the conversion mode handles unit IDs or timeouts.
Save the settings and let the module restart.
Add it in Epilykos
In Settings → Sources, add a Modbus device and give it a name.
Choose TCP. Enter the module's IP address as the host, 8899 as the port, and set the Gateway
type from the table above. Set the Unit ID to your inverter's Modbus address, often 1.
Pick the profile for your inverter or BMS, press 📥 Load Profile Registers, and keep or rename the suggested metrics.
Press Test Modbus to check that it reads, then Save changes. A poll of 30 seconds is a sensible start.
Troubleshooting
| Symptom | Likely cause | Fix |
|---|---|---|
| Timeouts, no readings | Wrong baud rate or parity, or A and B swapped | Check the inverter's manual, and swap the two wires. |
| Connects, but every read fails | Wrong gateway type for the module's work mode, or wrong unit ID | Match the table above, and check the unit ID. |
| Works at first, then stops | The module's Wi-Fi dropped, or its address changed | Use a DHCP reservation or a fixed IP, and prefer Ethernet if you can. |
| Odd failures while another tool is open | Two programs are using the module at once | Close the vendor tool. Two clients on one RS-485 bus can collide, and Waveshare doesn't document the module's connection limits. |
| Garbage values | The serial settings don't match the device, or it's the wrong profile | Recheck the baud rate, parity and profile. |
| Can't reach the module's web page | Your computer isn't on its subnet | Join the module's own Wi-Fi, or give your computer an address like 10.10.100.253. |
Good to know
- The module can also act as a Wi-Fi access point, an MQTT gateway or an HTTP client. Epilykos doesn't use these.
- Modbus ASCII isn't supported by the module's conversion mode.
- For the module's own settings in detail, see Waveshare's wiki page and user manual.
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