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

Hi All, I am in the same position trying to connect EW11A to a KH inverter and part of the original question was:
"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?"
With my KH9 inverter I have the 16 pin connector but it is not clear from pin descriptions whether there is the requested power supply pins; if so which pins and if there is no power there where is the best place to get power for the EW11A from?
(Ideally from the inverter somewhere rather than separate power supply)

Thanks

I believe that you need a separate power supply.

I used a PoE Ethernet cable, which feeds power into the adapter via the ethernet cable (you do need a PoE switch, I used a small 100mbps PoE switch for this, but check that the voltage etc is correct since there are various PoE specs). PoE power works over a considerable distance.

Hi all,

Just had my solar install during our house reno. However I was not present and not sure if the tools Nathan mentions in his guide were left, in particular the blue tool and more importantly the red pins used to attach the wires he says " pins are approximately 2cm in length and have red ends"

Does anyone know where to get these?

if you are using CAT5 UTP (which you should be) then you dont need any pins as it is solid core wire.
On the back of the plug you will see little orange "buttons" above each hole, just push them down with a small screwdriver to open the clamp inside and push the wire in, when you release them the wire will be held......simples
If you REALLY need pins then this sort of thing....but they need to be quite long
https://www.amazon.co.uk/dp/B0F82SV8M3? ... title&th=1

Thanks, I need to get a reel of cat6 anyway, so hoping the thickness, awg, of that will also work.

Lovely setup btw, how do you find your EPS?

initially disappointed as it was taking several seconds to switchover.....now it is less than a second which, although not the promised "zero disruption" is more acceptable.....I have a small battery backed UPS on the broadband and wifi so we dont really notice it

Gosh I thought these things were once in blue moon, but sounds like you have had to use it for real a few times! Glad it works.

here in mid Suffolk we do experience a fair few power cuts....hence the EPS!