Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
Hi

I saw this video showing that it is now a modbus server on the newer inverters.
https://www.youtube.com/watch?v=q8A32xMifmA

I tried using my H3 Smart 15kW but get this error:

changed to Error reading registers. Type: RegisterType.HOLDING; start: 31000; count: 91; slave: 247 from tcp://IP_ADDRESS:502: Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received)

Master : 1.30 Slave : 1.00 Manager : 1.18

Has anyone had any luck? Firmware version or some thing needs to be enabled?
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Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
That’s my video. Does your inverter have an integrated data logger or a plug in module?
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2 x KH Hybird Inverters (Parallel Mode)
1 x H1 Gen1 (Solar Mode)
1 x H1 Gen2 WL (Testing, Modbus and API development)
24 x HV2600 (62.4kWh)
32 x 490w across 4 arrays

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Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
It's got the integrated datalogger (Type: WL-H3-G2).
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
I have similar (integrated datalogger (Type: WL-H3-G2) + Device: H3-9.9-Smart)

I can't find the ip on my lan / anyway to customise it.

I can connect to the wifi of the device (using the wifi W* and password mtmt2020 - but there is no configuration page?
"In the address bar, type 192.168.1.1.
This will open the dongle's configuration interface"

Stuck as would be cool to integrate this into Home assistant
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
Yeah getting same error - I redid the wifi network and snagged the ip:
Error connecting to inverter (friendly name: "FoxEss"). Error reading registers. Type: RegisterType.HOLDING; start: 31000; count: 91; slave: 247 from tcp://192.168.68.106:502: Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received)
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
I might have to raise something with the home assistant project, as using my phone and an app, it can read the registers! Just home assistant app can't.

Getting close

https://imgur.com/a/bqPdLNc
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
Got it working, seems a few others had similar issues!
https://github.com/nathanmarlor/foxess_ ... ssions/994
"Answered by williamjeccles
2 days ago
You don’t need a modbus device. Just use the inverters ip address and set the integration to direct lan using the latest beta version and it will work. Smart and WL inverters have a tcp modbus server built into them."

Use the beta version of the release and make sure your inverter updated to the latest version.

Awesome to get the modbus info directly in home assistant now.
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
Trentan wrote: Tue Dec 23, 2025 1:25 pm Got it working, seems a few others had similar issues!
https://github.com/nathanmarlor/foxess_ ... ssions/994
"Answered by williamjeccles
2 days ago
You don’t need a modbus device. Just use the inverters ip address and set the integration to direct lan using the latest beta version and it will work. Smart and WL inverters have a tcp modbus server built into them."

Use the beta version of the release and make sure your inverter updated to the latest version.

Awesome to get the modbus info directly in home assistant now.
I am getting the "Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received)" error.

What version of firmware fixed the issue for the H3 Smart?
Re: Modbus server via the included wifi module for the new H1-Gen2-WL and H3 Smart models
You have to select the most recent beta release / version (not the standard one).

Think a few others had similar issues and a beta release fixed it.
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