FoxESS Community - Owners & Installers Forum

I have a FoxESS KH8 hybrid inverter installed outside and I'm trying to connect it to Home Assistant using the foxess_modbus integration for real-time monitoring and PredBat battery optimisation.
My inverter has the following firmware versions:

Master: 1.6
Slave: 1.02
Manager: 1.58

I've established that the built-in FoxESS WiFi dongle has Modbus TCP locked down (Manager firmware 1.58), so I've ordered a RUANI EW11A-0 RS485 to WiFi adapter to connect via the RS485 port.
I have a few questions I'm hoping someone can help with:

1. Which pins on the KH8 are RS485 A and RS485 B? I can see from the menu structure there is a COM/RS485 connector but I need to know the exact pin numbers
2. Is there a 5V or 12V auxiliary power output on the comms connector that could power the EW11A, or will I need a separate power supply?
3. Has anyone successfully connected an EW11A to a KH8 and if so any tips or gotchas?

thanks in advance

broaders wrote: ↑Tue May 19, 2026 11:49 am 1. Which pins on the KH8 are RS485 A and RS485 B? I can see from the menu structure there is a COM/RS485 connector but I need to know the exact pin numbers

thanks in advance

Check the connection types here
https://github.com/nathanmarlor/foxess_ ... ring-Guide

For reference, I have a KH7, and it uses the square shape 16-pin connection
https://github.com/nathanmarlor/foxess_ ... onnector-1

Something I personally found confusing when I wired mine up was that it was not obvious from the diagram whether the pin layout was from the top of the connector looking down, or from the underneath looking up towards the pins. What helped was comparing it to the position of the pre-existing CT clamp wires.

the pins are actually numbered inside the connector....but you need young eyes to be able to read them !!

I couldn't even see the bare wires after stripping the ethernet ... it was mostly poke and hope.

Next time I would want to get some thicker RS485 comms cable rather than using ethernet.

you should stick with CAT5 UTP it is 0.5mm diameter
as per the previously linked Github thread these are the connections so you would be looking at pins 3 & 4