Skip to content

Crowtail- CurrentPower Sensor


The Crowtail- CurrentPower Sensor will solve all your power-monitoring problems. Instead of struggling with two multimeters, you can use this breakout to measure both the high side voltage and DC current draw over I2C with 1% precision.It is use the INA219B chip that much smarter - it can handle high side current measuring, up to +26VDC, even though it is powered with 3 or 5V. It will also report back that high side voltage, which is great for tracking battery life or solar panels.

Model: CRT00455C

Crowtail- CurrentPower Sensor.jpg


Measuring up to +26VDC

Simultaneously measure current and voltage


Corwtail IIC interface

IIC address: 0x40



This demo is going to show you how to measure the voltage and current when the DC motor working. Here we use Crowtail as a load and measure it's voltage and current.

1.Software Installation

Download "" for arduino boards, unzip and put it in the libraries of Arduino IDE by the path : ..\arduino-1.x.x\libraries;

Cope this code and upload it into your arduino board.

#include <Wire.h>
#include <Adafruit_INA219.h>

Adafruit_INA219 ina219;

void setup(void) 
  while (!Serial) {
      // will pause Zero, Leonardo, etc until serial console opens

  uint32_t currentFrequency;


  // Initialize the INA219.
  // By default the initialization will use the largest range (32V, 2A).  However
  // you can call a setCalibration function to change this range (see comments).
  // To use a slightly lower 32V, 1A range (higher precision on amps):
  // Or to use a lower 16V, 400mA range (higher precision on volts and amps):

  Serial.println("Measuring voltage and current with INA219 ...");

void loop(void) 
  float shuntvoltage = 0;
  float busvoltage = 0;
  float current_mA = 0;
  float loadvoltage = 0;

  shuntvoltage = ina219.getShuntVoltage_mV();
  busvoltage = ina219.getBusVoltage_V();
  current_mA = ina219.getCurrent_mA();
  loadvoltage = busvoltage + (shuntvoltage / 1000);

  Serial.print("Bus Voltage:   "); Serial.print(busvoltage); Serial.println(" V");
  Serial.print("Shunt Voltage: "); Serial.print(shuntvoltage); Serial.println(" mV");
  Serial.print("Load Voltage:  "); Serial.print(loadvoltage); Serial.println(" V");
  Serial.print("Current:       "); Serial.print(current_mA); Serial.println(" mA");


2.Hardware Installation

CurrentPower Sensor ----- Crowduino1 ---- Crowduino2

IIC pin ----------------- IIC port

Intput"+" ----------------- 5V

Output"-" ------------------------------------- 5V

Null -------------------- GND ---------------- GND


Open the serial monitor and then observe the information.