Shelly Sensor Interface for Shelly Plus Devices (Add-On)

The Shelly Plus Add-On represents a sophisticated galvanically isolated sensor interface designed specifically for integration with Shelly Plus ecosystem devices. This compact module enables seamless expansion of your smart home or industrial automation system by providing dedicated interfaces for various external sensors while maintaining complete electrical isolation for enhanced safety and signal integrity. Engineered with precision, the device serves as a bridge between your primary Shelly Plus unit and multiple sensor types, allowing for comprehensive environmental monitoring and data acquisition capabilities without compromising system stability. This interface module transforms standard Shelly Plus devices into versatile monitoring stations capable of handling both digital and analogue sensor inputs. The galvanic isolation ensures that sensor circuits remain electrically separated from the main power system, preventing potential ground loops and protecting sensitive electronics from voltage surges or interference. Whether you're monitoring temperature variations, humidity levels, or other environmental parameters, the Shelly Plus Add-On delivers reliable performance while maintaining the sleek, minimalist design philosophy characteristic of the Shelly product range.

Technical Specifications

• Power Supply: 3.3V DC via host device
• Interface Compatibility: Shelly Plus series devices
• Digital Inputs: 1-Wire protocol support
• Analogue Input: Single channel 0-3.3V range
• Reference Voltage Output: 3.3V precision reference
• Pull-up Resistor Output: 3.3V through 4.7kΩ resistor
• Operating Temperature: -20°C to +60°C
• Isolation Rating: Galvanic isolation between sensor and main circuits
• Connector Type: Screw terminal blocks

Key Features

• Galvanic Isolation: Complete electrical separation between sensor circuits and main power system for enhanced safety
• Multi-Sensor Support: Compatible with DHT22 humidity/temperature sensors and up to five DS18B20 temperature sensors simultaneously
• Flexible Power Options: Dedicated sensor power supply terminals with precise voltage regulation
• Dual Input Capability: Combined digital and analogue input channels for versatile sensor integration
• Reference Voltage Generation: Built-in precision voltage reference for sensor calibration and operation
• Secure Mounting System: Locking bracket mechanism ensures reliable physical connection to host device
• Standardised Colour Coding: Clearly labelled terminals with intuitive colour scheme for straightforward installation

Primary Applications

The Shelly Plus Add-On finds extensive application in environmental monitoring systems where precise temperature and humidity tracking is essential. In residential settings, it enables comprehensive climate control systems by monitoring multiple rooms or zones simultaneously. Commercial installations benefit from its ability to monitor equipment temperatures in server rooms, refrigeration units, and HVAC systems. Industrial applications include process monitoring where multiple temperature points need tracking, while maintaining electrical safety through galvanic isolation. The device also serves educational and research purposes where reliable sensor data acquisition is required for experiments or environmental studies.

Installation requires careful attention to electrical safety procedures and should only be performed by qualified personnel familiar with low-voltage systems and sensor integration. The device's design prioritises both functionality and safety, making it suitable for both professional installations and advanced DIY projects where proper installation protocols are followed.