ACS712 current sensor- A Complete Guide

Published on February 16, 2022 , Last modified on July 25, 2024
by Hommer Zhao
current sensor

Load detection can be a complex process without the right equipment. This is where the ACS712 current sensor module comes in handy. Our guide will explore all the critical recent sensing insights of the module.

What is the ACS712 Current Sensor?

Figure 1: A technician checking for faults in electrical appliances

It is a sensor with 2.1kVRMS voltage isolation properties and current detection capabilities. The sensor operates via the principle of the Hall effect. Therefore, such kinds of sensors can change magnetic signals to electrical signals. 

Hence, the process is handy for processing the rate of current flow.  

ACS712 Current Sensor Pin Configuration

Figure 2: An Electrical Switchboard

The Features of ACS712 Current Sensor

Figure 3: The Sensor can measure DC power

  • Has a bandwidth of 80kHz.
  • It can measure both AC and DC.
  • The hall effect sensor is available in 30A, 20A, and 5A modules. 
  • The sensor’s output sensitivity range is 66 to 185 mV/A.
  • Features a low-noise type analog signal path.
  • You can set the device’s bandwidth via a filter pin.
  • Has an internal conductor resistance of 1.2 mΩ.
  • Its offset output voltage is stable.
  • It has an analog output voltage. Thus, it is compatible with MCU.
  • The sensor is capable of enabling isolation from load during operation.
  • Features an almost zero magnetic hysteresis effect.
  • Its total output error at a TA of 25°C is 1.5%.

How does the ACS712 Current Sensor work?

Figure 4: Magnetic Field Illustration

Essentially, current sensors work through two modes, namely: 

In our case, the ACS712 current sensor will operate via the indirect sensing mode. On the other hand, current sensors employ the alternative direct sensing technique. Hence, you can measure the recent drop by applying Ohm’s law with such kinds. 

Here’s a brief explanation of how ACS712-30A sensors operate. 

  • First, the electric current will flow in the Hall-Effect current sensor via its IC. 
  • Next, the Hall effect-based linear current sensor will detect the electric current via a magnetic field. 
  • In turn, the sensor will create a voltage. This voltage is proportional to the magnetic field that detects the current.

ACS712 Current Sensor Alternatives

Figure 5: A Technician repairing a circuit board. 

Grove – 10A DC Current Sensor (ACS725)

It’s an excellent alternative to the ACS712, characterized by lousy linearity and low sensitivity. Among the key advantages of this module over the ACS712 includes:

Grove – ±5A DC/AC Current Sensor (ACS70331)

It is similar to the ACS712 in that both can operate under AC or DC. Nonetheless, its differentiating features include:

Typical Applications of ACS712

Conclusion

As you have seen, the above sensor is an essential component in electronics and electric systems. Therefore, you can connect it to all electrical appliances to prevent overcurrent, among many other vital uses. In addition, If you would like further insights on the working of this sensor, reach out to us anytime. 

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Hommer Zhao
Hi, I'm Hommer Zhao, the founder and Chief Editor at WellPCB. With extensive experience in the PCB industry, I oversee all content to ensure it meets the highest standards of accuracy and insight. We proudly serve over 4,000 customers globally. For inquiries or more information, don't hesitate to reach out. Your satisfaction is my top priority!