I have a customer who wants to measure the AC line current into his device. The input is standard 120V, single phase AC. They require isolation and 2% accuracy. This is a sub metering application. Of course, they want it as cheap as possible. I don't have specs on isolation rating.
Can they use the AD7757 to measure just the current? If not, is there any cheap and easy way to measure the AC current. The microcontroller they are using provides multiple A/Ds that can be used. They are considering the Allegro ACS712 as well.