Shelly Plus Add-on Sensor Interface

Shelly Plus Add-on is a galvanically isolated sensor interface for all Shelly Plus relays. Use it to measure temperature and humidity or connect various analog and digital sensors to enhance complex automation and efficiency.

When the Shelly Plus Add-on is added to a Shelly Plus device, it must be activated in the app, after which it is possible to activate the sensors you have connected to the device.

Note, installation must only be performed by a certified electrician.

Supported devices:

• 5 x DS18B20
• 1 x DHT22
• NTC resistors with a nominal resistance of 10 kΩ and β=4000 K
• Photoresistors
• PIR sensors
• Soil moisture sensors
• Ultrasonic proximity sensors
• Capacitive liquid level sensors
• Sound detectors
• Other analog sensors with 0 - 10 V output voltage

Usage examples:

• Reed switch: add a reed switch to the Plus Add On device to monitor the garage door open/close position. Recommended with Shelly Plus 1.
• Liquid level sensor: add a liquid level sensor to the Plus Add On device to monitor the water level of your pool or aquarium. Recommended together with Shelly Plus 1 or Plus 1PM.
• Heating: add two DS18B20 temperature sensors and measure supply and return temperatures.
• Wind: thanks to the wind sensor, the awning can automatically retract when it is too windy. Recommended with Shelly Plus 2PM.
• Soil moisture: add a soil moisture sensor so the irrigation system can start automatically when the soil is too dry. Recommended together with Shelly Plus 1.

The Shelly Plus Add-on does not operate independently. The device must be connected to any Shelly Plus device, which enhances the functionality of the Shelly Plus device. The Shelly Plus Add-on does not need to be plugged into the Shelly Plus unit because it is equipped with pins that automatically connect to the Shelly Plus unit. The two units are galvanically isolated from each other.

Device connections:

• Inputs: 1 analog input, 1 digital input
• Output: 1 reference voltage output, 1 reference voltage output through pull-up resistor, 2 grounding connectors*
• 1-wire connection: 3 sensor power outputs (connected to the same PCB trace), 3 sensor data connectors (connected to the same PCB trace), 3 grounding connectors*

* Connected to the same PCB ground layer.

Specifications:

• Model: Shelly Plus Add-on
• Operating voltage (DC): 3.3 V (from Shelly device)
• Power consumption: < 0.5 W (without sensors)
• Max current VCC: 10 mA
• Max current VREF output: 1 mA
• VREF+R1 output resistor: 10 kΩ
• Digital input: -15 V ... 0.5 V (true) / 2.5 V ... 15 V (false) / configurable in settings
• Operating temperature: -20 °C to +40 °C, indoor use only
• Dimensions: 37 x 42 x 15 mm
• Weight: 105 g