tMTH-4 - Temperature and humidity meter with Modbus interface (4 x AHT/AM)

tMTH-4 is a temperature and humidity measurement module with Modbus RTU interface. It features four independent I²C buses, dedicated for connecting AHT20/AM2301B temperature and humidity sensors, allowing for a total of 4 sensors.
Temperature and humidity data is made available via Modbus registers.

The tMTH-4 is primarily designed to function as an extension module for LK4 or LK3.5+ devices (also compatible with LK3.9), enabling scalable and distributed temperature and humidity monitoring.
A ready-to-use configuration file for these devices is available, allowing for quick and hassle-free integration.

Basic features

• Supports up to 4 AHT20/AM2301B temperature and humidity sensors (via 4 independent I²C buses).
• Provides sensor readings via the Modbus RTU protocol.
• Compatible with LK4, LK3.5+, and LK3.9 devices.
• Can be connected to a PC via USB to access the configuration console.

Technical specifications

Default setup

Out of the box, the tMTH-4 is pre-configured with:

• Modbus Slave ID: 1
• I²C bus frequency: 20 kHz for all 4 inputs

Additional information

More information about the device, usage, and custom Modbus module configuration for LK4/LK3.5+ is available at https://tinycontrol.pl/en/tmth-4/.