I am a first time project attemptor! I am looking for guidance on what Arduino Hardware and Shields/Sensors to use if I wanted to do a AC Voltage (RMS) Data Logger. I havent seen any posts previously in the forums that address this. Anyone that can direct me to where get this info I would greatly appreciate it.
Also posted here. Please don't cross post.
I'd run the AC through a step-down transformer (6 or 12V), then through a rectifier (diode), a voltage divider (2-resistors) to bring it down below 5V, then add a parallel capacitor to filter/smooth the DC.
Do you have a multimeter to calibrate the thing?
In case you don't know this, the peak is about 1.4 times the RMS and the capacitor will charge-up to the peak (minus the forward diode drop). And, with a light load the transformer put-out a bit more than its rated voltage. So, you will need to calibrate it.
How frequently are you going to measure & log the voltage and what are you going to do with the data? (Store it on an SDcard? Send it immediately to a PC? Etc.?