Main Content

The ArduINA226 power monitor

In the past I have developed various projects of ammeters based on Hall effect current sensors such as the ACS712, or on High-Side Current-Sense Amplifiers such as the MAX4080SASA or made with operational amplifiers. All these systems have an analog output which must then be digitized. The INA226 sensor has a digital output and incorporates a 16-bit ADC for which a high accuracy and precision is obtained.
It measures current and voltage and calculates power while Arduino communicates with the chip, presents the measurements on an LCD display and stores them on a micro SD card. This chip operates with a maximum voltage of 36 volts while the current is limited only by the shunt used.
There are some libraries for the INA226 chip, I used the Korneliusz Jarzebski library which seems to me quite complete even if I had to make some changes to two functions.
There are numerous possible applications for this monitoring tool: battery-powered devices such as scooters or pedal-assisted bicycles, photovoltaic panels, etc.

The INA226 sensor
In current measurements with the shunt there are two ways to insert it:
1) To ground (low-side): the shunt is connected between the load and the ground.
2) owards the power supply (high-side): the shunt is connected between the power supply and the load.

The INA226 integrated circuit, by Texas Instruments, is a digital device that measures the current with a high-side or low-side shunt and also measures the voltage, calculates the power and provides a multifunctional alarm.”

Link to article