I'm needing to find a way to monitor power use for a flat that my parents have, their power bill was $690 last month, since they're not home most of the time or on the farm it seems very high. There's 1 20a fuse from the fuse board heading into the flat. I was thinking of putting an inductive clamp onto the phase wire heading into the flat and tapping it from that point to see current draw, but wondering if anyone here has a solution that has an easy to read meter, is cheap (ideally) and simple to install and maintain? I'm not worried about my parents power use since it's 1 meter for the house and flat, but I've come to a conclusion that the flat is using quite a bit of electricity.
I've thought about building it around an inductive clamp and an Arduino but really need it to be as simple as possible, so if you know of a decent packaged product designed for this let me know :)