I was wondering if anyone could point me to some good referances on how to attentuate an AC signal (120/240v 60hz) down to managable levels for reading with a ADC. The ADC will likely be 0-5v input. I was looking at using opamps to attenuate but would appreciate some direction.
If you need isolation then an isolation step-down transformer (120/240-to-5) is a good option ..
If you don't need isolation try to design a simple 2-resistor voltage divider ..
Below is an example of an input of a digital voltmeter with voltage selector ..