Shelly Plus Add-on

What is Shelly Plus Add-on?

Shelly Plus Add-on is a galvanically isolated sensor interface for all Shelly Plus relays. Use it to measure temperature and humidity using its 1-Wire terminals, or connect various analog and digital sensors for complex automation and higher efficiency.


Highly compatible

Shelly Plus Add-on is compatible with most Arduino sensors! Use its digital or analog inputs to measure your desired parameters and create complex automation scenes based on the sensor data.

User interface

Basic wiring diagrams




Size (HxWxD): 37x42x15 ±0.5 mm / 1.46 x 1.65 x 0.59 ±0.02 in
Weigh: 105 g / 3.70 oz
Shell material: Plastic
Screw terminals max torque: 0.1 Nm / 0.89 lbIn
Conductor cross section: max. 1 mm² / 17 AWG
Conductor stripped length: 4.5 mm / 0.18 in
Color: Black
Ambient temperature: -20 °C to 40 °C / -5 °F to 105 °F
Humidity: 30 % to 70 % RH
Max. altitude: 2000 m / 6562 ft
Power supply voltage AC: N/A
Power supply voltage DC: 3.3 V (from Shelly plus device)
Power consumption: < 0.5 W (without sensors)
VCC max. current: 10 mA
VREF OUT max. current: 1 mA
VREF+R1 OUT resistor: 10 kΩ
Shelly Plus Addon supporting devices: Shelly Plus devices:
  -Shelly Plus 1/1PM
  -Shelly Plus 2PM
  -Shelly Plus i4/i4DC
  -Shelly Plus 0-10V Dimmer PM
  -Shelly Plus RGBW PM
  Shelly Gen3 devices:
  -Shelly 1/1PM Gen3
  -Shelly i4/i4DC Gen3
  -Shelly Dimmer 0/1-10V PM Gen3
Temperature reading: Depends on the DS18B20 or DHT22 sensors
Humidity reading: Depends on the DHT22 sensor
Digital input: -15 V to 0.5 V (True) / 2.5 V to 15 V (False)*
Analog input range: 0 to 100%
Analog input report threshold: 1%**
Voltmeter range: 0 to 10 V
Voltmeter report threshold: 0.1 V**
Analog input / Voltmeter accuracy: Better than ±5%

Installation of Shelly devices must be done by a qualified electrician or authorised installers.

Use Cases

Motion-controlled lights

Motion-controlled lights

Shelly Plus Add-on can also be connected to a PIR sensor to light up rooms that you occasionally use around the house. This way, when you enter the room, the light will come on for as long as you need it to.
Irrigation only when needed

Irrigation only when needed

Having a beautiful garden is not an easy task and automating your irrigation system can save you time and optimize your costs. Together with a soil moisture sensor, Shelly Plus Add-on can trigger Shelly Plus 1 to turn on the irrigation only when necessary, always skipping the rainy days.
An awning that follows the weather

An awning that follows the weather

Outdoor motorized awnings offer pleasant shade for your guests on sunny days. However, a strong, unexcepted wind can damage them beyond repair. By combining it with a wind sensor connected to the Shelly Plus AddOn, Shelly Plus 2PM can automatically close the outside awning to protect them from the wind. Additionally, Shelly Plus Add-on with a rain sensor can trigger Shelly Plus 2PM to open the awning just in time to protect your guests.
Control your lights based on luminosity

Control your lights based on luminosity

Together with an LDR (photoresistor), Shelly Plus Add-on can trigger Shelly Plus 2PM to open the blinds when the room is too dark and it's still daytime. Additionally, when luminosity is low, Shelly Plus Add-on can trigger Shelly Plus 1 to turn on the lights at just the right time.
Always informed

Always informed

Using Shelly Plus Add-on and two DS18B20 sensors, you can easily measure the precise temperature inside your aquarium, as well as the room temperature. Based on this data, you can maintain a comfortable and healthy environment for your pets. Additionally, you can connect a liquid level sensor to the Add-on, and always be sure that the water level is at its optimal level.
Garage door position

Garage door position

You can connect a reed-switch sensor to Shelly Plus Addon's digital sensor and follow the state of your garage door. This way, you will always know whether it is open or closed when you're away and take appropriate action.
Shelly Smart Control

Shelly Smart Control

Shelly Smart Control - one app to control your spaces, energy consumption, and expenses

Download the Shelly Cloud app for Android and iOS

Download Shelly Cloud App on Apple App StoreDownload Shelly Cloud App on Google Play store


Shelly Plus Add-on Launch