Messuring battery voltage and current with INA219 inconsistent values.

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1

I'm messuring a batteries voltage and current as it's being charged by a solar panel. But I get really inconsitent and weird vaules. Here's my values

Bus Voltage:   3.62 V
Shunt Voltage: -2.41 mV
Load Voltage:  3.62 V
Current:       -24.10 mA
Power:         87.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: -0.01 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: -0.01 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: -0.01 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: -0.01 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.62 V
Shunt Voltage: -2.41 mV
Load Voltage:  3.62 V
Current:       -24.10 mA
Power:         87.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.62 V
Shunt Voltage: -1.05 mV
Load Voltage:  3.62 V
Current:       -24.00 mA
Power:         87.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: 0.00 mV
Load Voltage:  3.61 V
Current:       -0.10 mA
Power:         0.00 mW

Bus Voltage:   3.61 V
Shunt Voltage: -0.01 mV
Load Voltage:  3.61 V
Current:       0.00 mA
Power:         0.00 mW

Bus Voltage:   3.62 V
Shunt Voltage: -2.41 mV
Load Voltage:  3.62 V
Current:       -24.10 mA
Power:         87.00 mW

I'm linking a picture to my circuit as well.

Solar_Panel_Circut.jpg
Solar_Panel_Circut.jpg4032×3024 453 KB

2

Lets see the code so we can find the problem...

3

Here's the code

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

Adafruit_INA219 ina219;


void setup(void) 
{
  Serial.begin(115200);
  while (!Serial) {
      // will pause Zero, Leonardo, etc until serial console opens
      delay(1);
  }

  uint32_t currentFrequency;
    
  Serial.println("Hello!");
  
  // 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).
  ina219.begin();
  // To use a slightly lower 32V, 1A range (higher precision on amps):
  //ina219.setCalibration_32V_1A();
  // Or to use a lower 16V, 400mA range (higher precision on volts and amps):
  ina219.setCalibration_16V_400mA();

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

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

  shuntvoltage = ina219.getShuntVoltage_mV();
  busvoltage = ina219.getBusVoltage_V();
  current_mA = ina219.getCurrent_mA();
  power_mW = ina219.getPower_mW();
  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");
  Serial.print("Power:         "); Serial.print(power_mW); Serial.println(" mW");
  Serial.println("");

  delay(2000);
}