In US electricity monitoring scenarios, must both sides of voltage be measured?

[Bill.Thomson]

@dBC

Sense have a fairly neat approach you can see in their install video:

IIRC, she has, or at least had, a Sense device. I say had, because of this post:

Power Quality Monitor

FYI: I found this interesting post on a teardown of the Sense device:

I don’t know if that means she sells them, or if she sold the one she bought, to forum user whatnick.