Fox KH9.9 Has 16pin connector for Comms (like H1/3) But RS485 shows no activity

[GTR2734]

Hi

Ive just recently had a KH9.9 inverter + 41.93kwh EQ4800 stack installed.

I'm installing a Waveshare POE modbus adapter. I've got that up and running on the home network, but keep getting
"Error connecting to your adapter or inverter. Ensure the adapter is properly configured and is correctly wired to your inverter (see the setup link above), then try again. Details: Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received)"

Which from the guides, appears to be incorrect pinning of the comms cable

As you can see, i've pinned it assuming 485B is pin 3 and 485A is Pin 4. This is how its wired back to the Waveshare, and ive tried swapping the cables over on the waveshare, and also have rechecked the comms plug multiple times.....


At a loss as to if this is the actual correct pinout, as all manuals etc show KH series having a round pin connector, yet mine has the 16P square connector.

Any help greatly appreciated, would love to get cracking on HA integrations

[Dave Foster]

Your pin outs look correct, it is pins 3&4 - 485A should be wired to the waveshare A, and 485B to B

No response received could be cabling or the config incorrect IP address / slave id, waveshare protocol settings or baud rate.

It sounds like you’ve read the guides for the waveshare but i’ll leave the link here for you to check https://github.com/nathanmarlor/foxess ... TH-%28B%29

[GTR2734]

Thanks. I might grab a multi meter tomorrow and see if theres any voltage coming out of the inverter.

Have checked the communication setting on the inverter as well (ID 247).

Have ethernet comms etc to the waveshare (i'm using a POE injector to power it, but have full ethernet connection to the device). Flashed latest firmware, have done a reset on it and updated all the settings from default as well.

Appears to be entirely the comms between the inverter and waveshare. Its all brand new cable which i crimped/heatshrunk and also put in conduit (away from any AC power cables as well.....)

Def a head scratcher....

[MaterialBarracuda48]

I am sure you have done your connections fine, but worth a double-check.

I assume you have used your multimeter to check for continuity from your pins on the front of the connection to your waveshare device?

I myself had an error with the CT Clamp pins, as I pulled my plug to pieces and the pin was "open" a little and not making contact, do the pins look nice and tight on 3 & 4?

[GTR2734]

Yeah i'll do continuity as well to make sure cables are ok between.

I'm sure it will be something stupid, but certainly frustrating, especially how everything else worked perfect straight away (and i took my time, routed cables, heat shrink, conduit etc). Even went and bought crimp pins rather than just sticking wire in the terminals......

[MaterialBarracuda48]

Well you did a better job than me for sure!
Hopefully with a multimeter you can cover a few simple tests, so best of luck for tomorrow.

[AlanHarwood]

Did you manage to solve the problem?
I have the same issue (on a KH10.5). Connectivity is OK and the voltage between the two cables is 0.46 volts, i.e. it's connecting to something in the inverter, but nothing that foxESS-modbus will accept.

[MaterialBarracuda48]

Did you manage to solve the problem?
I have the same issue (on a KH10.5). Connectivity is OK and the voltage between the two cables is 0.46 volts, i.e. it's connecting to something in the inverter, but nothing that foxESS-modbus will accept.

Have you checked on the inverter control to see if ID is set to 247?
Have you tried swapping the pair over, just in case you got that wrong?
What HW are you using to interface with the Modbus?

I don't have all the answers, but these few questions could help.

[AlanHarwood]

Yes, I have tried swapping the to leads over (even though the voltage between the pair seemed in the right direction), and I did check the inverter setting was 247.
I am using a cheap RS485 to USB converter. I don't think that is the problem because I have a second KH10.5 (but an older one with the old plug), and that works fine with the same converter (I have two RS485 to USB converters, and I tried swapping them over, and the fault stayed with the inverter).
I was hoping someone might say , "It's not pins 3 and 4, it's 7 and 8" or something similar!

[MaterialBarracuda48]

Not really sure then Alan I'm afraid, you have ruled out the USB device having swapped that over.
Maybe someone knows some other things you can try.

[Dave Foster]

It is still pins 3 & 4 on the 16 pin, but I gather the numbering can be confusing as they are numbered from the front?, you should be able to work it out as CT1 will be connected to pins 7 & 8.

Some of the cheaper USB devices can be a bit flaky, if you can swap the converter over to the working KH to test it that would eliminate that.

What error do you get when you try and connect (in HA, System, Logs?)

[AlanHarwood]

I found my problem: it was the cable.
The only thing that I couldn't swap between inverters, so by elimination, it seemed likely to be the culprit.
Fitting a new cable solved the problem, and I was able to install both inverters into the FoxESS-modbus setup.

Thanks for the helpful inputs.

Alan