Waveshare RS485 Connection Method

[Daz42]

Hi there, firstly thank you for this integration. I was using it over the LAN connection to my H1. As I want to control the BMS, I purchased the Waveshare POE server and followed the directions precisely to set it up. I have wired 485A to pin 4 and 485B to pin3 in the inverter. Also used a multi meter to ensure I had a good connection. When setting up the modes in HA, using the correct IP address and the port, I am 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 4 bytes (0 received).

I think I'm getting a TCP connection to the Waveshare but may not be getting any data from the inverter. Any ideas?

Thank you!

Daz.

[canton7]

I think I'm getting a TCP connection to the Waveshare but may not be getting any data from the inverter

That's what it looks like to me as well. What you've described looks correct also.

Check the slave ID on the inverter is correct (Settings -> Communication -> RS485 -> Device ID) -- it should be 247. Other than that I'm not sure I've got anything to suggest apart from the obvious: make sure that all of the settings are correct, that you've definitely got the IP of the waveshare, that you didn't break a connection or wire when you plugged the connector back into the inverter, etc. Most of these sorts of questions seem to be resolved with "A wire fell out" or similar.

[FozzieUK]

If you were using the LAN connection, you need to disable the ethernet on your inverter before the RS485 will work.

Common mistakes are the RS485A(4) must be wired to A of the device, and RS485B(3) to B and also with the Waveshare there are often settings errors, always double check them, particularly those which relate to TCP_Server, Transfer protocol being Modbus_TCP to RTP, and the device port being 502.

It is best to test using modpoll first from a laptop or desktop connected the the same subnet,

You can download that from here if you don’t have it -
https://www.modbusdriver.com/modpoll.html

Then issue this command at the command prompt -
modpoll.exe -m tcp -p 502 -a 247 -t 3 -0 -1 -c 16 -r 11000 192.168.x.x (<<< replace this with your waveshare IP address)

And hopefully you should get a response

[Daz42]

Thank you for that! I looked at my H1 menus and there doesn't seem to be an option to disable the LAN port - it was always enabled and all I did was configure a static IP address. There is a remote access option but not sure if it's related.

[FozzieUK]

There used to be a disable/enable option but it’s been quite a while since i’ve been into the communications, Ethernet menu, i’ll double check that later when i’m at my inverter.

As Antony said, check your slave is set at 247, and all the waveshare settings and then see what result you get from the modpoll 👍

[Daz42]

Under communications, there are no settings to disable the LAN port - at least on my H1. I've downloaded ModPoll and run it using the command line you suggested (with my IP address set). It looks like I am reaching the Waveshare but getting this error message:

PS D:\Software\Home Assistant\FoxESS Integration\Modpoll3.10\win> .\modpoll.exe -m tcp -p 502 -a 247 -t 3 -0 -1 -c 16 -r 11000 192.168.1.150
modpoll 3.10 - FieldTalk(tm) Modbus(R) Master Simulator
Copyright (c) 2002-2021 proconX Pty Ltd
Visit https://www.modbusdriver.com for Modbus libraries and tools.

Protocol configuration: MODBUS/TCP, FC4
Slave configuration...: address = 247, start reference = 11000 (PDU), count = 16
Communication.........: 192.168.1.150, port 502, t/o 1.00 s, poll rate 1000 ms
Data type.............: 16-bit register, input register table

-- Polling slave...
Reply time-out!

So this looks like the Inverter isn't responding. I've checked the wiring to pin 4 (485A) and pin 3(485B) with a multimeter using the grub screws as contact points to ensure that there is a solid wire grab and all looks good there.

[Daz42]

Ok, I found the issue. I have two Waveshares - the other is for my other property subject to this solution working. I swapped them out and it's working. Thank you very much both Antony and Dave. I am now able to control my BMS settings - I really didn't want to plug in the WiFi adapter again! So the bit we learned in addition to the solution is that the H1 6.0 E version 0.59 does not have a LAN port enable/disable and does affect the Waveshare integration using 485A and 485B.

[canton7]

Good news! Sounds like it was some configuration on the Waveshare then?

the H1 6.0 E version 0.59 does not have a LAN port enable/disable and does affect the Waveshare integration using 485A and 485B.

What exactly do you mean by that?

[Daz42]

It was a fault Waveshare - all of the settings were correct and I had reset to default to check before configuring again. I'll return the bad one. Reference to the LAN port to discussion with Dave as he had suggested that the LAN port had to be disabled before using the 485 pins - but in my case there wasn't a setting and the 485 pins worked regardless.

[FozzieUK]

Great, glad you’ve got it working ok 👍

Before you send the faulty one back, if you have updated the firmware it has been known to scramble it’s config - if you put a link across then NC pins for more than 5 seconds, it will factory default and ‘usually’ it works afterwards 😃

[Daz42]

Good info, I will give that a try. Not surprising with value Chinese kit - a reset might work!

[Daz42]

Ok, that worked Dave. Both Waveshares work now. I'm super grateful for your help.

[canton7]

Nice one!

I've added a Troubleshooting section to the wiki page with this info.

[FozzieUK]

Brilliant 👍 , i’ve been really impressed with them for the money.
@canton7 thanks Antony, I was going to do that when I got back later, there’s been a few that have suffered from this ☺️