Can anyone point to resources, reviews or experiences on monitoring power usage in 240v ac (US)?
Looking at the new energy dashboard features …. I have opower integration of my electricity usage and a nice graph. However most of my power usage is from a heat pump, and EV charger, and maybe a garage heater. All are 240v, larger current loads. So the new feature is something about graphing device usage with overall usage. So that would be cool to add
I started searching online and it doesn’t seem especially positive. I see a few clamp meters with integrations but also see reviews that they’re not very accurate.


The CT clamp reads the current without having to be directly connected to the wire. It just ‘clamps’ onto the leg and is non invasive. https://en.wikipedia.org/wiki/Current_clamp
Here’s one of my panels with the clamps on. The top clamps read total power, the individual clamps below are reading one leg each. for a 240v you need both since each leg is only supplying 120. My dryer also sometimes only uses 120v when it’s not actively heating.