Current sensor ACS712-5A

The ACS712 sensor allows you to measure current up to 5 A and transfer measurements to the microcontroller of the Arduino board. The module can be used to measure and control current in such devices: charger, overload protection board, power supply, etc. The work of the module is to use the Hall effect. This effect occurs as a result of the influence of the Lorentz force on electrons, which changes the movement of electrons in the presence of a magnetic field. As a result, an EMF appears due to the flow of current at the edges of the plate.

The current sensor module is designed based on the ACS712T chip in the SOIC package. Inside the chip are a Hall sensor and a copper conductor through which current passes, creating a magnetic field. On different sides of the plate, the density of free particles is different, which causes a potential difference, which is recorded by the Hall sensor. The main feature of the microcircuit is the large thickness of the conductor, which allows the passage of current many times greater than the permissible value of the microcircuit.

The sensor is connected to the Arduino platform through 3 pins. The VCC and GND pins are used to supply power, and the OUT pin is used to transmit the fixed values of the sensor or receive data from the microcontroller device, and connects to the analog port of the Arduino board.

Terminal J1 is used to connect the measured power supply. External source terminals are clamped with copper bolts for accurate current readings.

The module board is supplied with 5 V voltage from the microcontroller device or from an external power supply. The presence of power is signaled by an LED that is connected to the power buses. With a passing current equal to zero, depending on its direction of flow, the output voltage will change towards zero or to the supply voltage.

To work with the module in the Arduino IDE development environment, you need to download the ACS712 library and install it yourself in the Libraries folder.

Module Specifications:

Chip ACS712T
Supply voltage, V 5
Measurement range, A -5 ... +5
Accuracy, % 1.5
Sensitivity, mV/A 66
Bandwidth, kHz 80
Operating temperature, °С -40 ... +80
Module dimensions, mm 31.4 x 13 x 14.