On a 240V circuit on the U.S. split-phase system, a complete circuit has current flow moving through one hot wire and returning on the other hot wire. The Current Transducer just has to be anywhere on that circuit. (ie - it's just slid over the one wire.)
The two wires going to power the display connect to a 240V connection not only to power the display, but also to let it know the voltage. By multiplying voltage and current, power in watts can be known and displayed. Multiplying that by clock-time gives energy in watt-hours.
If you wanted to measure current on two different 120V circuits (each on the two legs of the 240V system), you would need a CT on each of the two hots. Most total home energy monitors include two CTs for exactly that reason.
__________________
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Last edited by bennelson; 07-23-18 at 12:16 PM..
Reason: clarification
|