Let EVCC battery control your HA Battery Integration (evcc can switch HA settings via HA-APIs)

[h3llrais3r]

I've read your documentation (https://github.com/marq24/ha-evcc/blob/main/HA_AS_EVCC_SOURCE.md) about using HA sensors for defining the grid, pv and battery meters.

I'm now wondering if the battery control part of the battery meter can also be done in the same way?
What I mean is, can we define a HA sensor to implement the batterymode settings?
If yes, is there an example on how to do this?

I know I can do it directly via modbus, but that's not always that stable and it requires multiple registers to be read/written.
If I'm able to define this in HA and call it through the api, it would be easier.

[marq24]

IMHO this should be doable via the https://developers.home-assistant.io/docs/api/rest/ POST /api/states/<entity_id> endpoint - probably you don't need a 'sequence` if there is a single entity that provide the toggle in HA.

If you need to switch/set multiple entities in HA, then you might like to create an automation for this and then you just trigger this automation via an helper entity (toggle this helper will start the automation)...

[h3llrais3r]

Actually I also noticed that we can also trigger a service: POST /api/services/<domain>/<service>
As far as I can see, I can probably trigger a HA script that does all the work.
Or like you said: create a sensor that sets a value an then trigger some automation that does all the work.
Will try it out and keep you posted.

[h3llrais3r]

To conclude: I'm using a combination of /api/states and /api/services to create the custom meters. 😉

[UDicke]

very interesting!
I believe you just have to set the price limit in evcc and the rest will be done in evcc to control the battery. Setting the price limit could be done in HA. (I did so) As far as I know setting the price limit is currently the only way to control the battery in evcc.
look here : #31
am I wrong?
@h3llrais3r your new evcc template saj.h1 should hopefully work for that soon.

[h3llrais3r]

very interesting! I believe you just have to set the price limit in evcc and the rest will be done in evcc to control the battery. Setting the price limit could be done in HA. (I did so) As far as I know setting the price limit is currently the only way to control the battery in evcc. look here : #31 am I wrong? @h3llrais3r your new evcc template saj.h1 should hopefully work for that soon.

@UDicke This is mainly because I want to bypass the saj.h1 template for now, and use custom meters instead.
The problem is that I'm connecting directly to the SAJ H1 inverter via it's AIO3 module (modbus over tcp), but it seems that this connection is not very stable (also mentioned by other people in home assistant community topic about SAJ).
Due to that, I'm getting often error responses via modbus over tcp, which makes it very hard to test (see my PR for the SAJ H1 template).
So I first want to get everything working via custom meters (and HA sensors/srcipts) as I don't have a dedicated rs485 device to connect to my inverter (which should be far more stable).

[UDicke]

I connected via the "rs485 device" at a very early state of my work/research to connect with HA.
The result was: this connection is very frequently (10 times a second as far as I remember) used to contact the smartmeter delivered with the inverter for regulating the inverter.
The best way to communicate is via modbus over TCP/IP in my opinion.
see also here: evcc-io/evcc#18097 (comment)

Again the question

So I first want to get everything working via custom meters (and HA sensors/srcipts)

How do you do this? Is there some description? I´d like to understand this just to be able to use it for "whatever..." 😊

[h3llrais3r]

Here an example of how I do it:

Basically, for all sensors/battery control, I'm using home asisstant sensors.
Most of then are just reading out sensors which I already have in home assistant (so I don't need additional modbus connection)
For the battery control, I created a select template with different modes, and when a mode is selected, I'm executing some actions (writing to the SAJ registers, in the same way as I've created the template).
Since these reads/writes are going over mqtt (modbus over mqqt), I feel that these are far more stable than doing an additional modbus integration (as in the saj-h1 template I've created).

So as long as I don't find the modbus over tcp via IAO3 module stable enough, I'm going to keep it like this.
Doing my first tests now, and I now get the additional options for battery control in evcc. 😉

[h3llrais3r]

And now "live" in action:

I've started a charging session and the battery mode is switched to "hold" ;)