Gravity: I2C Digital Wattmeter

The Gravity: I2C Digital Wattmeter is a high-precision measurement module capable of monitoring voltage, current, and power up to 26V and 8A. Powered by the TI INA219 chip, it provides accurate real-time telemetry for students, makers, and engineers analysing battery life, solar systems, and motor loads.

High-precision current and voltage sensing

Equipped with a TI INA219 zero temperature drift chip and a 2W 10mΩ alloy sampling resistor, the board delivers 4mV voltage resolution and 1mA current resolution. It achieves a maximum relative error of no more than ±0.2% under full-scale conditions following a simple manual calibration.

Bidirectional high-side measurement

The module measures bidirectional high-side currents directly from the positive supply line. This allows users to track both charge and discharge states via positive and negative current readings, which is ideal for battery fuel gauges and solar circuits.

Arduino microcontroller connection

The sensor interfaces seamlessly with standard 5V and 3.3V development boards such as the Arduino Uno via the Gravity I2C interface. It allows real-time current and voltage monitoring directly within embedded projects.

Raspberry Pi integration

Designed for broad platform compatibility, the wattmeter operates reliably with 3.3V logic systems including the Raspberry Pi 3B. Users can log continuous energy consumption data for automation and smart monitoring systems.

Electronic module power evaluation

Use the sensor to assess the power draw of individual modules or complete project setups to calculate overall battery runtime. It can also detect motor overloads by monitoring real-time current spikes.

Solar power management

The module is suited for tracking the power generated by solar panels, stored in battery banks, and drawn by system loads. Its high power range up to 206W handles diverse renewable energy experiments.

Configurable I2C addresses

An onboard 2P DIP switch allows you to select between four distinct I2C addresses: 0x40, 0x41, 0x44, and 0x45. This enables the connection of multiple wattmeters along the same I2C bus.

Downloads & documentation

• Product wiki (DFRobot)