Home Assistant remote limiter functionally without direct modbus or RS485 modification of the GTN wifi dongle

[garylankford8]

Remote limiter functionality can, at least in my use case, be accomplished in Home Assistant using the esp8266-wifi-dongle-example.yaml without modification of the wifi dongle or connection to the RS485 port by leveraging helpers and automations to control power output limits using number.output_limit, number.start_voltage and number.shutdown_voltage.

After creating some helpers and automations with some logic help from my new friend Copilot who is very logical, but not talkative, I decided to run the idea through my other new friend Gemini, who really likes to talk, but denies that, and blames all the talk on Google Assistant...

Gemini claimed to have full knowledge of the GTN1200 and argued that there was no way to gain limiter functionality in home assistant except by using modbus and the RS485 port. I finally showed him the example.yaml mentioned above... I then asked...

Can the wifi dongle version of the GTN 1200 be limit controlled without modification of the wifi dongle for connection to the RS485 port using automations in home assistant?

Gemini AI:
"Let's evaluate the provided ESPHome configuration (name: soyosource-wifi-dongle) for dynamically changing the output limit without a direct RS485 connection to the Soyosource GTN 1200.
Analysis:
The configuration you've provided uses the esphome-soyosource-gtn-virtual-meter custom component, specifically designed for the WiFi version of the Soyosource GTN and its OEM WiFi dongle.
Here's a breakdown of the relevant parts:

• external_components_source: github://syssi/esphome-soyosource-gtn-virtual-meter@main: This line confirms that you are using a custom component that interacts with the Soyosource GTN's WiFi dongle.
• uart: ...: This defines the UART (serial) communication, which is how the ESP32/ESP8266 communicates with the Soyosource WiFi dongle, not directly with the GTN 1200's RS485 port. The WiFi dongle itself communicates with the GTN, likely via some proprietary protocol or an internal serial/RS485 connection that you are not directly accessing.
• soyosource_display: ... protocol_version: SOYOSOURCE_WIFI_VERSION: This further reinforces that the communication is tailored for the WiFi dongle's protocol.
• number: - platform: soyosource_display output_power_limit: name: "${name} output power limit": This is the crucial part. The output_power_limit is exposed as an ESPHome number component.
  Does it create a number that could be dynamically changed for output Limit?
  Yes, absolutely.
  The output_power_limit configured as a number component in ESPHome means:
• Home Assistant Integration (or MQTT):
     * If you use api: (ESPHome Native API - recommended): Once this ESPHome device is integrated into Home Assistant (which is the typical use case for ESPHome), the output_power_limit will appear as a number entity. You can then dynamically change its value directly from the Home Assistant UI, automations, scripts, or even voice assistants. ESPHome handles the communication with the device.
     * If you use mqtt: (as configured): The output_power_limit will be published to your MQTT broker, and you can send commands to change its value via MQTT topics. Home Assistant can also integrate with MQTT entities.
• Dynamic Change: Because it's an ESPHome number component, its value can be changed in real-time. When you change the value (e.g., in Home Assistant), ESPHome will send the corresponding command through the UART to the Soyosource WiFi dongle, which then relays it to the GTN 1200.
  Without connection to the Soyosource GTN 1200 RS485 port?
  Yes, that is precisely the point of this configuration.
  You are not directly connecting to the GTN 1200's RS485 port. Instead, you are connecting to and communicating with the Soyosource WiFi dongle via UART (serial). The WiFi dongle itself acts as an intermediary, handling the communication with the GTN 1200 (likely via its internal RS485 or another bus).
  In summary:
  This ESPHome configuration effectively creates a dynamically changeable output limit for your Soyosource GTN 1200, and it achieves this without requiring you to directly connect to the GTN 1200's RS485 port. It leverages the existing Soyosource WiFi dongle as the bridge for communication." ...close Gemini.

It might be that the direct connection to the modbus is faster, I dunno, but I thought maybe there would be somebody out there who might rather not modify dongles and would find this application useful...

If so, example helpers and automations may follow, or even better, perhaps someone smarter than me might teach me some things...

And for you others, please forgive me for wasting precious minutes of your lives if you read to this point and found nothing...

[syssi]

Long story short: This solution changes the inverter settings multiple times a day. These settings are written to a flash memory which will wear out very quickly (~10.000 cycles). You will damage your device!
Please use the RS485 to drive the inverter!

[garylankford8]

So, not a great idea... 😕 Thanks for that!