Export Limit or Power Limit control possible through RS485?

[Sven177]

Hi Guys,
I am running a Solax X1-Mini and successfully made the RS485 interface sending the data to Home Assistant through an ESP32 and some according TTL converter Board. The Code provided here worked like a charm - thanks to all involved for that :-)

Now that I have kind of live data at hand, the next big thing would be either controlling the Inverter´s Export Limit or it´s Power Limit, using an existing sensor that is already present in Home Assistant. I don´t have a Smart Meter that would take that task (the Inverter is a bit further away from the electrical cabinet in the garage, feeding just 1 phase), but I am running a Shelly 3EM energy monitor, that is monitoring all 3 phases - and of course some "overal power" entity in Home Assistant, that will tell the direction (negative when exporting to the grid) as well as the Wattage.

So my question: would it be possible to kind of "emulate" the smart meter on the RS485 connection, to control the power output of the Inverter based on the measurement of the Shelly Energy Monitor?

I´m not a professional programmer (not by far), but would be thankful for some answers, hints, examples or other tips into the right direction... ;-)

Thanks & Regards
Sven

[syssi]

The esp8266-meter-gateway.yaml of this project does exactly this. A MQTT topic is consumed to retrieve the power demand.

Please be aware of one important thing: You can either monitor the inverter using RS485 or control the output power. You cannot have both simultaneously because the operation mode of the RS485 port must be changed.

[Sven177]

Hi Syssi,

thanks for your fast reply. OK, that wouldn´t be too dramatic, since I still have some other methods of retreiving data (cloud service, WiFi Switches for measuring etc).
I actually saw that code snippet as well, but I wasn´t able to figure out how to "set" the according entity, that will tell the Inverter what power output it should set. Also I am definitely a noob regarding those MQTT functions (having only WMBusMeter configured to check the water meter).
So I guess I need to have the Shelly Entity for the overall power somehow as this MQTT source for this code?
And also I think the Inverter has to be set to a certain export limit as well afterwards - correct?
For I know when there is no meter connected, enabling the export control function will result in a "meter fault" error...

Regards and a nice evening!

[Sven177]

OK. I had those when using the Code-Button (but only one at the beginning and at the end) - and then I pasted between those. But afterwards it was totally weird looking in my browser - so I thought something was screwed up 😅

[syssi]

I have to prepare a test setup later the week to get an idea what's going on here.

[Sven177]

OK, no need to hurry. Thanks a lot for all your help 😊
Just let me know if you found something or if you need some more data or logs to investigate...

[syssi]

Okay. I've verified your YAML. Everything looks good. If you increase the log level to VERY_VERBOSE you should see something like this

[VV][solax_meter_gateway:094]: New power demand received (40.00). Resetting inactivity timeout (152875)

as soon the new power demand is received. At the moment it looks like your inverter isn't attached and in "export control" mode because the inverter acts as Modbus master and polls the ESP for power demand updates once per second. On each request the ESP will respond (and the log will be informative). At the moment everything is silent because there is no request activity.

[Sven177]

Awesome - thanks.
Will do so, check and report...

[Sven177]

Now it seems working as intended!

[14:35:13][V][sensor:043]: 'powermeter0': Received new state 208.990005
[14:35:13][D][sensor:094]: 'powermeter0': Sending state 208.99001  with 1 decimals of accuracy
[14:35:13][VV][solax_meter_gateway:090]: New power demand received (208.99). Resetting inactivity timeout (354235)
[14:35:13][W][component:214]: Component api took a long time for an operation (0.05 s).
[14:35:13][W][component:215]: Components should block for at most 20-30ms.
[14:35:14][VV][api.service:140]: send_sensor_state_response: SensorStateResponse {
  key: 4033027473
  state: 208.99
  missing_state: NO
}
[14:35:14][V][text_sensor:013]: 'solax-meter-gateway operation mode': Received new state On
[14:35:14][VV][solax_meter_modbus:069]: RX <- 01.03.00.0E.00.01.E5.C9 (8)
[14:35:14][VV][uart.arduino_esp32:167]:     Flushing...
[14:35:14][V][solax_meter_modbus:127]: SolaxMeterModbus write: 01.03.02.00.D1.78.18 (7)
[14:35:14][V][sensor:043]: 'solax-meter-gateway power demand': Received new state 209.160004
[14:35:14][D][sensor:094]: 'solax-meter-gateway power demand': Sending state 209.16000 W with 0 decimals of accuracy
[14:35:14][VV][api.service:140]: send_sensor_state_response: SensorStateResponse {
  key: 4033027473
  state: 209.16
  missing_state: NO
}
[14:35:14][V][text_sensor:013]: 'solax-meter-gateway operation mode': Received new state On
[14:35:14][VV][solax_meter_modbus:069]: RX <- 01.03.00.0E.00.01.E5.C9 (8)
[14:35:14][VV][solax_meter_modbus:069]: RX <- 01.03.00.08.00.04.C5.CB (8)
[14:35:14][VV][uart.arduino_esp32:167]:     Flushing...
[14:35:14][V][solax_meter_modbus:181]: SolaxMeterModbus write raw: 01.03.08.00.00.00.00.00.00.00.00 (11)
[14:35:14][VV][scheduler:226]: Running interval 'update' with interval=1000 last_execution=355138 (now=356146)
[14:35:14][VV][solax_meter_modbus:069]: RX <- 01.03.00.08.00.04.C5.CB (8)
[14:35:14][VV][uart.arduino_esp32:167]:     Flushing...
[14:35:15][V][solax_meter_modbus:181]: SolaxMeterModbus write raw: 01.03.08.00.00.00.00.00.00.00.00 (11)
[14:35:15][VV][solax_meter_modbus:069]: RX <- 01.03.00.0E.00.01.E5.C9 (8)
[14:35:15][VV][uart.arduino_esp32:167]:     Flushing...
[14:35:15][V][solax_meter_modbus:127]: SolaxMeterModbus write: 01.03.02.00.D1.78.18 (7)
[14:35:15][V][sensor:043]: 'solax-meter-gateway power demand': Received new state 209.160004
[14:35:15][D][sensor:094]: 'solax-meter-gateway power demand': Sending state 209.16000 W with 0 decimals of accuracy
[14:35:15][VV][api.service:140]: send_sensor_state_response: SensorStateResponse {
  key: 4033027473
  state: 209.16
  missing_state: NO
}
[14:35:15][V][text_sensor:013]: 'solax-meter-gateway operation mode': Received new state On
[14:35:15][D][text_sensor:064]: 'solax-meter-gateway operation mode': Sending state 'On'
[14:35:15][VV][api.service:174]: send_text_sensor_state_response: TextSensorStateResponse {
  key: 2382757277
  state: 'On'
  missing_state: NO
}'''

[Sven177]

Awesome!! 😀

[syssi]

Good job! You can reduce some load if you decrease the log level to INFO for example and remove the debug section from the uart component.

[Sven177]

Good morning,

I would have another question 😁

Would it be possible to also implement some kind of an "Override" switch, that would cause the Meter Gateway to not listen for the according sensor of Home Assistant to set the power demand, but just use a fixed value (like 500W) then?
So technically "disabling" the Export Control on the Gateway side when needed, by just using a "fixed" power demand when this Override switch is used, while leaving the actual Export Control Function (and it´s threshold) still activated at the Inverter.

I tried to use some kind of If-Statement, that would either use the Shelly Sensor or a fixed value depending on a switch state, but I can´t make it...(seems like these If-Statement things are quite tricky in Home Assistant)😅

[syssi]

In general this is feasible and no big thing. The christmas time is pretty busy and I would like to have a look between the years. Could you create an issue / feature request?

[Sven177]

Hi,
cool - thanks for the feedback. OK, I will try to do that (first time 😅)
Also no reason to hurry - for it works like a charm currently. That Override-Function would be just the cherry at the top 😊