I am trying to read current produced by a small solar cell. When I just hook up the cell in direct sunlight, it gets about 0.66 volts, which is about right. But when I hook it up to the Arduino through the ACS712 Hall effect current sensor, it shows 5.0 volts. I know that it should be printing about 2.5 volts, and therein lies the problem. My diagnosis is that it is for some reason printing the voltage received from the Arduino; my question is how do I get it to print the voltage from the solar cell?
Do you want to know the current or the voltage of the solar cell ?
Can you upload your sketch ?
And please attach a diagram or photo of the wiring, so we can see how everything is connected.
You have checked the ground connection to the ACS712?
Figured it out. Turns out there were a couple screws for trimming, one was turned so it was reading high.
Thanks for your help!