1-0 Ammeter

Hello,

I want to build an AC ammeter that i want to interface to a pic micro.
It should be able to detect devices from 8 to 1000 W running on 220V.
I'm not actually looking to get any specific values, i just want to tell the chip if there's a device that is running or not.
I have an idea about how to detect that current: toroid inductor surrounding the wire that is carrying the current.
However, it is with the values\kind of wire\inductance\number of turns that i get lost and you guys come in.
It would be best if there are inductors that do just that and that i can get ready made from any local electronics store since spinning one of those is a pain...

Thanks

Search for Current Transducers on Digikey. They have clamp on ones so you don't have to rewire the main circuit.

They generate a small AC voltage directly proportionate to the amount of current. Just rectify and measure.

You can also look for Current Sense Transformers. Your local electronics store might have something like this. Here's an example.

Thanks for your suggestions this is exactly what i was looking for.