C-clamp current monitoring

[Hydronic] did some tests to make his own current sensor using a c-clamp wrapped with wire. He tried several different cores including an aluminum carabiner, the C-clamp, and what he calls a u-lock (removable chain link). There is some success here that could be improved with cleaner winding and by adjusting readings based on the length of wire used in the wrapping.

This did make us perk up a bit right off the bat. Reader [Mure], who tipped us off about this, suggested that this could be used to make your own Kill-a-Watt without including it in the circuit. We made the jump to house monitoring. We’d love to have a data tracker for our home circuits to curb wasteful energy use. Perhaps we’ll try to make our own sensors and produce a diy Cent-a-Meter.