+It depends, those clip on CT coils look like you wouldn't need to power down, just as long as the output of the CT isn't open circuited.
If you need to disconnect to thread a doughnut one on then you'd have to power down as there really isn't any other option.
Spark123. Look at the diagram on my second post, #5.
This meter and most I have been studying have L1, L2, L3, N off the bus bar, into the meter. although Disinfo said the ones he uses go to the primary winding on the CT.
Don't quite get the theory here. The current drops down as it travels across the CT windings and goes to the meter after being reduced to 5va or so. How does this measure the flux or current running through the cable?