I actually looked at tweetawatt but it doesn't answer any of the questions I have. I currently have a P3 Kill-a-watt that I hacked into, soldering wires to the voltage pin, current pin, and ground of the quad op amp inside the Kill-a-watt. And I have those pins run through an analog digital converter on my Arduino Uno microcontroller. One thing I messed up on is that the LCD on the Kill-a-watt isn't working correctly after I put everything back together, it just doesn't show any numbers, but it is still working. My question is, what is SUPPOSED to be coming from the Voltage and Current pins (AD0 and AD4 I think on the quad op amp). I have actually hooked my alarm clock to my Kill-a-watt and tested to see what data I can get from it on my Arduino, and I see pretty low numbers. I actually checked to see the voltage coming from the voltage pin with a multimeter, when it was hooked to the wall outlet, and I got around 2-3V and wasn't sure what I was even seeing. And when I hooked my alarm clock to my Kill-a-watt, and ran both Voltage and Current pins through the ADC of my Arduino, I saw that the voltage changed constantly and the current was stable. So my ultimate question is what is supposed to be coming from the voltage and current pins? Say if the LCD of the Kill-a-watt was working and and it was hooked up to the wall outlet only, and saw 120V AC on the LCD, is that what should be showing from the voltage pin also? Or if say an appliance was hooked up to the kill-a-watt, would whatever voltage shows up on the LCD be the same number as the one coming out of the voltage pin? I am really confused on that part, please let me know if you can. Thank you for your time.