FoxESS Community - Owners & Installers Forum

I have a Waveshare adapter powered by PoE and I was just getting timeouts. I have switched to a Waveshare USB device and get the same.

I have connected pins 3 and 4 to B and A and pin 16 (COM) to GND.

Polarity correct
Baud: 9600, 8N1
Slave: 247

I'm testing with mbpoll

mbpoll -m rtu -p none -b 9600 -a 247 -r 1 -c 1 /dev/ttyACM0

I've been trying this for days and rewired a couple of times but I don't seem to be getting anywhere.

Can anyone suggest where I might be going wrong?

Do you have a picture of the rear of the plug?
I use the USB waveshare device, and only wired up the A & B pins to it.

I'll get one later but on the top row I have them centre top and the one to the right of that which equates to mirror on the front. If that makes sense


- - B A -

As the top row. And I have it the same way up as the manual with the slightly offset row at the top

penguin wrote: ↑Sat May 02, 2026 5:06 pm I'll get one later but on the top row I have them centre top and the one to the right of that which equates to mirror on the front. If that makes sense


- - B A -

As the top row

That seems right to my head, as seen from behind (the direction you add the wires in)
1 being top left, and 5 being top right

1 2 3 4 5
- - B A -

As you are using a waveshare device that is a TCP to RS485 and should be configured as TCP to modbus protocol and the correct baud rate (9600,N,8,1), I would have expected that your modpoll would be using -m tcp (not rtu)

Also not seeing a register address to poll, for example this is the command I use on modpoll to get the model name from the inverter

Modpoll -m tcp -p 502 -a 247 -t 4 -0 -1 -c 16 -r 30000 192.168.x.x (the waveshare IP address)

I started with the TCP device and then bought the USB device to rule out device issues. I'll try addressing the register specifically which is something I haven't done