sine signal as input to arduino Analog pins

Projects General Guidance
1

I connected a acs712 sensor to an ac load and obtained the required output through arduino (in simulation)
My worry is that the output of acs712 is seen as pulsating Dc almost like a pure sine wave ( but always positive ) current seem to be very less . Is it okay to arduino if i give such an output of this sensor directly to the arduino A0 pin ?

ive attached an image for reference

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2

Is it okay to arduino if i give such an output of this sensor directly to the arduino A0 pin ?

What matters is the input voltage so it looks OK, but bear in mind that the Arduino may take a reading at any point in the waveform

3

See, actually the output remains to be 2.5v when load current is zero . but afterwards when the load current flows continuously , the voltage fluctuates like 2.8v to 2.1v each instant and behaves like a sine wave . thats all ! is it okay ?

4

is it okay ?

That sounds OK as long as you have common GND with the Arduino but note that the Arduino may catch the output at any of its range of output voltages when analogRead() is used

5

@OP

Your ACS712 sensor is simply bad; please, replace it by a good one. A good ACS712 produces DC voltage (not a fluctuating one being modulated by the 50Hz line frequency) which is proportional to the RMS value of the 220V line voltage.

6

Sensor is working fine.
The output voltage with no current being measured is Vcc/2 , so 2.5 V if the supply voltage is 5V.
Sensitivity is 185 mv/A.
As previous posters have indicated, the Arduino A/D can sample the sensor voltage anywhere in the output waveform, which will probably yield nonsensical results, unless the sampling rate is much higher than 50HZ.

7

Normal behaviour.
The ACS712 outputs VCC/2 (may not be 2.5volt) without current, and a sine wave superimposed on that DC voltage with AC current flowing through it.

Would not use an ACS712 to measure a mains powered 3-phase motor (OP's cross-post).
Safer to use current transformers.
Leo..

8

Wawa:
Normal behaviour.

Is it normal that the ACS712 will produce a sine wave modulated output signal?

9

GolamMostafa:
Is it normal that the ACS712 will produce a sine wave modulated output signal?

Yes, if a sine wave current flows through the sensor, you get a sine wave output.
With a DC offset of half of the sensor's supply.
Offset AND gain are ratiometric, so "2.5volt" and "66mV/Amp" are only correct if sensor supply is 5.0volt.
If you measure the sensor with a ratiometric A/D (an Uno), then offset and gain errors are compensated by the A/D.
Leo..