KC868-A2 + SIM7600 LTE + Home Assistant – Relays & Sensors over LTE?

[WestfieldGhost]

Hi everyone,

I’m working on a setup with a Kincony KC868-A2 and a SIM7600 LTE module and I want to connect it to Home Assistant over LTE only.
At the moment I’m using Tuya Cloud, because it seems to be the only solution that officially supports LTE with this board.
My goal is to:

• Control the relays from Home Assistant
• Read inputs and sensor values (ADC, 1-Wire, etc.) remotely via LTE

Current situation:

• The device works fine in the Smart Life / Tuya app over LTE
  
• It also appears in my Tuya Developer account
  
• But in Home Assistant it shows as unsupported and I currently have no control at all
  

So my question is:
Is this device limited when used via Tuya Cloud, or has anyone managed to get full relay + sensor integration over LTE with it?
I’m not fixed on Tuya – it’s just the only LTE-supported method I’ve found so far.

If there is a better approach, I’m open to alternatives.

Has anyone here done this using:
• MQTT over LTE
• Or flashing the ESP32 with ESPHome or other custom firmware (without the original Kincony firmware)?

Important:
? I want to avoid any additional hardware or gateways.

Just the KC868-A2 + SIM7600 + LTE + Home Assistant.

Any ideas or real-world experience would really help.

Thanks in advance!

[admin]

A2 download KCS v2 firmware, use tuya app by 4G. also integrate to home assistant by MQTT. so that tuya app and home assistant can work at the same time.

[WestfieldGhost]

Hi everyone,

I would like to share my findings after doing very detailed testing with a Kincony KC868-A2 together with a SIM7600 LTE module, because I am trying to use this board entirely outside my home network.
In my setup, the KC868-A2 is never connected to LAN or Wi-Fi — it is installed remotely and has LTE-only connectivity. The goal is to control it fully through Home Assistant using the mobile data connection.

My intention is to:

• control the relays remotely over LTE
• read inputs and sensor values (ADC, 1-Wire, etc.) over LTE
• integrate everything directly into Home Assistant
• and operate the device without any LAN/Wi-Fi and without any extra gateways

The SIM7600 LTE module itself works perfectly. Over USB I verified with AT commands that the SIM is ready, LTE registration succeeds, the APN is accepted, NETOPEN works and the modem receives a valid mobile IP address. So the LTE hardware, SIM card and mobile data connection are all fully functional.

However, after installing the latest KCS V2 firmware on the A2, it appears that the firmware does not use the LTE data connection for any network communication. Tuya Cloud only works when the board is connected via LAN/Wi-Fi, and the option “connect by gprs (for board have gprs)” does not activate mobile data on the A2. When running on LTE alone, Tuya never connects.

The same applies to MQTT: it connects immediately when LAN/Wi-Fi is available, but stays disconnected as soon as the device relies on LTE only. The GSM section in the firmware only offers SMS and Call Test, and there are no APN fields, no PDP settings and no LTE data indicators anywhere in the UI.

Based on these tests, it looks like the SIM7600 establishes a full LTE data session, but the KC868-A2 firmware does not route Tuya or MQTT traffic over the mobile data interface. LTE on this model seems to be limited to SMS/Call, and mobile data is not used for Tuya or MQTT on the A2 at the moment.
This makes LTE-only remote control via Home Assistant impossible in the current firmware — which is exactly what I am trying to achieve.

So my question is:
Does the KC868-A2 firmware support LTE data for Tuya or MQTT at all, especially in a setup where the device is never connected to LAN/Wi-Fi and must operate exclusively over LTE?
If LTE data is supported, is there a specific firmware version or configuration needed to enable it?

Thanks in advance!

[admin]

already repied in another thread.