Modbus integration using the usb port

[ehoconnor]

I have just got a FoxESS H1 Hybrid Inverter H1-5.0-E is there any way of just using the USB port to install Modbus for the Nathan Marlor Home assistant integration. What I would like to do is just plug into the USB port where the fox data logger is and then have a modbus to wifi connection in one? Is this possible? If not what should I use. I have read the posts on integrating but my invertor layout seems different. Many thanks,

[Dave Foster]

No the USB port cannot be used for external ethernet connections.

To run modbus you need to get access to the RS485 communications of the inverter which can be found on the meter/ct connector.

If you have a new H1 inverter it will be a G2 and there are 2 possible connector configurations for the meter connection wiring, i've attached the schematic below - you need to connect to RS485 A/B pins (pins 3&4) - these need to be connected to an RS485 adapter.

Many people use the RS485 USB adapter which is cheap and easy to connect to a computer, my preference is the waveshare device which you connect to over ethernet.

[ehoconnor]

Thank you for the clarification. That is very helpful.

[L19YDC]

Hello,

Sorry to jump on this several months on - but I'm in need of connecting a modus to the H1 inverter too.
Looking at the wiring on the wave share USB RS485 connector there is 3 wire connections and you mention connecting pin 3 & 4, which wire goes to where & where is the GND connected to please?


Thanks

[Dave Foster]

It’s a balanced differential pair so you don’t need a ground, just 2 wires - the RS485A (pin 4) goes to the waveshare A connection, and the RS485B (pin 3) goes to the B connection

[L19YDC]

That’s Fantastic thanks Dave,

So I just need to cut into the two wires that the fitter has done for the CT and take my feed into the usb adapter?
Then I can plug the usb adapter into the machine running home assistant ?

Just struggling to see how the machine running home assistant will recognise the usb?

Thanks

[Dave Foster]

That’s Fantastic thanks Dave,

So I just need to cut into the two wires that the fitter has done for the CT and take my feed into the usb adapter?
Then I can plug the usb adapter into the machine running home assistant ?

Just struggling to see how the machine running home assistant will recognise the usb?

Thanks

Not sure I understand the bit about cutting into the 2 wires for the CT, the CT itself will be wired to 2 different pins (usually pins 7 & 8), unless the installer has put in a multi core cable for you to tap into ?

On the USB adapter, once it is plugged into the home assistant it will be recognised by the OS and should be found when the integration is loaded.

This is for a different adapter but is very similar and describes the process https://github.com/nathanmarlor/foxess_ ... -Converter

[L19YDC]

Ok Thanks ..... hopefully I can understand how to wire in the 2 wires to the RS485 connection on inverter.
Appreciate the links ........ now got to understand it all

[Dave Foster]

Ok Thanks ..... hopefully I can understand how to wire in the 2 wires to the RS485 connection on inverter.
Appreciate the links ........ now got to understand it all

No problem, if you need any help just shout.