A lightweight Arduino library for the ACS712 Hall effect current sensor. Supports both DC and AC (RMS) current readings with easy calibration.

• readCurrentDC(): Read DC current (e.g., batteries).
• readCurrentAC(): Read AC current (RMS) (e.g., mains).
• calibrate(): Automatically find the zero-point offset.
• Accuracy: Uses 100-sample averaging for high stability.
• setSensitivity(): Support for 5A, 20A, and 30A modules.

1. Download this repository as a ZIP file.
2. Open the Arduino IDE.
3. Go to Sketch > Include Library > Add .ZIP Library...
4. Select the downloaded ZIP.

#include <ACS712-driver.h>

// Pin A0, 5.0V reference, 1023 ADC resolution
ACS712 sensor(A0, 5.0, 1023);

void setup() {
  Serial.begin(9600);
  sensor.setSensitivity(0.185); // 0.185 for 5A, 0.100 for 20A, 0.066 for 30A
  sensor.calibrate();
}

void loop() {
  float amps = sensor.readCurrentDC();
  Serial.println(amps);
  delay(100);
}

Constructor.

• pin: Analog pin connected to OUT.
• voltageReference: System voltage (usually 5.0 or 3.3).
• adcResolution: ADC bit depth (usually 1023).

Sets the sensitivity in Volts per Ampere.

• 5A module: 0.185
• 20A module: 0.100
• 30A module: 0.066

Reads the sensor 100 times to find the average zero-point offset. Returns the calculated offset.

Reads the current value for DC circuits.

Reads the RMS current for AC circuits. Default frequency is 60Hz. This is a blocking function.

For applications where you cannot afford to block execution (e.g., LED or motor control).

Call this in your loop() as often as possible. Returns true when a new reading is available.

Returns the last calculated DC current value.

MIT License