Safe and easy way to measure AC mains voltage?

Projects General Guidance
1

I'm looking for a safe and easy way to measure 120VAC with my Arduino. Haven't really been able to find anything useful through my Googling. Is there a breakout board that would be able to solve this problem for me? I need a high resolution, as I'll be expecting the voltage to range between 0 and 120V, and I'm hoping to keep things as simple as possible.

Any help would be great!

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There is lots of useful information at openenergymonitor.

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Nice find, JohnLincoln.

@brandenc, you mention high resolution. The analog inputs are 10 bit, so your minimum will be roughly 120mV resolution. If that's not sufficient, you need to use an external analog-to-digital converter (ADC) with more bits.