DIY current sensor to arduino not working
The 33 ohm burden resistor is calculated for 100A. If the the noise level is at about 2% of the scale, you wouldn't get a clear signal until you draw at least 4 or 5A. I'd recommend to use a different (higher value) burden resistor while testing on the bench.

I used the exact same circuit to detect current consumption of some pumps a few years ago. It definitely works, within reasonable limits. Don't expect 1% precision from it.