Shelly Pro Sensor Add-on

The Shelly PRO Sensor Add-on is a galvanically isolated DIN-rail accessory that transforms compatible Shelly Pro devices into powerful sensor hubs. It provides two 1-Wire data terminals, two analog inputs (0-10 V), two digital inputs (±15 V) and one potential-free solid-state relay output — all in a compact module that mounts directly in the electrical panel alongside an existing Shelly Pro device. The module connects to the host device via Shelly's internal serial interface and is powered by 12 V from the host. This means no separate power supply, no additional network configuration and no external controller — sensor data flows directly into the host device's web interface, scripting, MQTT and automations. Galvanic isolation on all interfaces protects both the sensors and the host device in mixed-voltage environments. The Shelly PRO Sensor Add-on supports a wide range of sensors, including up to five DS18B20 temperature sensors per 1-Wire channel, DHT22 temperature and humidity sensors, NTC resistors (10 kΩ, β=4000 K), photoresistors, PIR sensors, soil moisture sensors, ultrasonic sensors and other 0-10 V analog sensors. The add-on is compatible with most Arduino sensors, making it well suited for both standard automation scenarios and specialized installation or prototyping projects. Compatible host devices: Shelly Pro 1, Pro 1PM, Pro 2, Pro 2PM, Pro 3EM, Pro Dimmer 0/1-10V PM, Pro Dimmer 1PM, Pro Dimmer 2PM and Pro EM-50. Since the Shelly PRO Sensor Add-on inherits the host device's connectivity, sensor data integrates seamlessly into the Shelly Smart Control app and your preferred smart home system — including Home Assistant, Athom Homey, Samsung SmartThings, Google Home, Amazon Alexa and KNX. Use Cases: Monitoring of temperature, humidity and open doors/windows from the panel, HVAC optimization using temperature and humidity sensors, Motion-based lighting with PIR sensors in hallways, storage and offices, Leak protection with digital water sensors and automatic shut-off, Smart irrigation with soil moisture sensors for greenhouses and outdoor systems, Specialized monitoring projects using Arduino-compatible sensors