Modbus to mqtt integration to HA

Third party integrations
1

Hi,

currently, I am working on an open source software named modbus2mqtt.
It will be available as docker image and as integration to HA.

It works as follows:
Known modbus device
The user selects a modbus controller (USB RS485 stick) from a list
He/she selects a slave.
If there is a “known” device configured for this slave, it will be detected and can be used in Homeassistant without any further configuration (MQTT discovery).

The device is unknown to modbus2mqtt
The user configures an own specification for the device. This configuration will contain the mapping from modbus data to mqtt topics. It will contain the conversion rules and the mqtt discovery information.
Then, the user saves the specification can can immediately use the new device in HA.

Contribution of Specifications
If a user created a specification, it can be published to the community. In this case, it can be used by everyone in the Known modbus device scenario above. The contribution is an integrated process. It happens on github. However, all interactions except authentication is integrated into modbus2mqtt

I assume, the application will be available by end of june '24.

In the beginning, it will support the following devices:

  1. Dimplex Heatpump (based on PCO5)
  2. Deye Inverter sun-*-sg04lp3-eu
  3. Wasserstandsensor
  4. Hutschiendstromzähler Eastron SDM72D-M-2

Any other modbus devices can easily be added (as long as there is a documentation of the protocol)

If this is of interest, please reply to this post.

2

That would be great! Especially if polling interval can be set, like below 5 seconds.

3

The polling interval can be set individually for each slave. It can be configured from 1 ms to whatever you like.

4

Great! (You mean in your code, not currently in HA, right?) Looking forward to it!

5

My device is a Sungrow inverter (SH10RT). Registers are here if you’d like to implement. https://github.com/mkaiser/Sungrow-SHx-Inverter-Modbus-Home-Assistant

6

Just wait for the software. It’s very easy to configure it on your own.
The point is:
Modbus2mqtt works best if you have the converter connected to your own RS485 connector.
It will immediately show the generated mqtt values. That way, it is very easy to configure the device correctly. It doesn’t make sense to configure a device, which you don’t have in your own modbus.
However, once it’s available, I can help you configuring it.

2 Likes
7

Looks promissing. Does it work in both directions, so one can also send commands to the modbus device? I want to control individual hvac fan units in every (guest)room via Sauter Control NRFC4 thermostats from HA.

8

Great project! Can it also be used with modbus TCP devices? I have several of this kind, but the modbus implementation in HA is very complicated to use and laggy for writing to modbus registers.Modbus to mqtt would be the perfect solution.

9

Any progress?