How to get access to modbus data (H3)

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m15k
Posts: 6
Joined: Wed Nov 08, 2023 5:00 pm

I already saw several plugins for home automation software, but they lack on guidance how to gain modbus data.

Is it possible to obtain modbus data via the wifi dongle somehow? If not what are the possibilities to obtain the data.
calum
Posts: 373
Joined: Fri Feb 24, 2023 11:00 am
Location: Stockport

https://github.com/nathanmarlor/foxess_ ... ring-Guide

It mentions the H1 but the same integration does also support the H3, albeit not all the same features: https://github.com/nathanmarlor/foxess_ ... d-Features

(this is because the H3 itself doesn't support them)
H1-3.7 / 6xHV2600 / 14x400W / RS485 Modbus->HA
FoxESS Modbus HA Integration
Contact Fox here
m15k
Posts: 6
Joined: Wed Nov 08, 2023 5:00 pm

Thanks for the link. I guess I missed the github Wiki.

What should I do when the modbus connection is already blocked by the meter to control the hybrid inverter?
calum
Posts: 373
Joined: Fri Feb 24, 2023 11:00 am
Location: Stockport

Have a look at https://github.com/nathanmarlor/foxess_ ... 1-inverter

Basically there is a single connector with multiple pins inside, the meter or CT clamp will be connected to two of those pins, if you want to get access to modbus you need to connect to two others.
H1-3.7 / 6xHV2600 / 14x400W / RS485 Modbus->HA
FoxESS Modbus HA Integration
Contact Fox here
m15k
Posts: 6
Joined: Wed Nov 08, 2023 5:00 pm

Ah I see. Thanks!
v1lad
Posts: 10
Joined: Thu Dec 07, 2023 9:25 pm

Hi All !
I am going to connect adapter with twisted pair cable. Before I started to disassemble H3 connector, would be good to understand how to fix the wire in the socket ? How should the end of the wire be prepared ? Thanks in advance for the help.

P.S. If anyone is interested, I'm going to connect the inverter to an adapter based on an ESP32 controller. The case is printed.
https://www.thingiverse.com/thing:3337686
FoxESS Hybrid-WR H3-8.0-E
FoxESS Batterie ECM 2900 Master/Slave with BMS
LiFePo4, 2,9 kWh x 3
Astronergy PV Modul CHSM54M-HC BL 400Wp x 20
calum
Posts: 373
Joined: Fri Feb 24, 2023 11:00 am
Location: Stockport

It's small grub screws. I would strip about 6-7mm of insulation and then fold the end over to provide more metal for the screw to grip. Be aware that especially if you're using solid core cable for this, it's pretty easy to break them so be gentle :)
H1-3.7 / 6xHV2600 / 14x400W / RS485 Modbus->HA
FoxESS Modbus HA Integration
Contact Fox here
ashley.hill
Posts: 1
Joined: Wed May 10, 2023 1:08 pm

v1lad wrote: Mon Dec 18, 2023 6:42 pm Hi All !
I am going to connect adapter with twisted pair cable. Before I started to disassemble H3 connector, would be good to understand how to fix the wire in the socket ? How should the end of the wire be prepared ? Thanks in advance for the help.

P.S. If anyone is interested, I'm going to connect the inverter to an adapter based on an ESP32 controller. The case is printed.
https://www.thingiverse.com/thing:3337686
Hi,

Did you manage to get this working. I will be attempting the exact same thing tomorrow.

Thanks,
Ash
Dave Foster
Posts: 561
Joined: Thu Oct 13, 2022 7:21 pm

ashley.hill wrote: Fri Jan 12, 2024 7:18 pm Hi,

Did you manage to get this working. I will be attempting the exact same thing tomorrow.

Thanks,
Ash
Yes this does work, there are quite a few H3 users using this integration.

Wiring instructions are here (but note that H3 has a different pinout to H1) https://github.com/nathanmarlor/foxess_ ... ring-Guide
v1lad
Posts: 10
Joined: Thu Dec 07, 2023 9:25 pm

Hi All !

Modbus error function code: 0x83 exception: 2

It seems that I have a communication via UART, but the response is wrong. What can be the reason for this?
I have made the issue here and attached log and config.
https://github.com/mypi-home/HA-ESPHome ... s/issues/1

P.S. Issue is solved. H3 model has other reg numbers. I found correct list here.
https://github.com/rsaemann/HA-FoxESS-H ... -Registers
RS485 is working.
FoxESS Hybrid-WR H3-8.0-E
FoxESS Batterie ECM 2900 Master/Slave with BMS
LiFePo4, 2,9 kWh x 3
Astronergy PV Modul CHSM54M-HC BL 400Wp x 20
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