The temperature and humidity sensor with Modbus RTU interface allows reliable monitoring in technical rooms, server rooms, and industrial installations. Thanks to communication via RS-485, it can be easily integrated into systems with a LAN controller and Modbus converter. It offers a wide temperature measurement range of -55 to +125 °C with high accuracy, and stable operation is ensured by power supply in the range of DC 5–24 V. A practical cable length of 0.8 m facilitates installation even in hard-to-reach places.