I have built a controller and have a metering device with a CT Clamp.
i have put all 3 phases through the one clamp. but having strange results…
Do the 3 phases being out of sync affect the way a CT clamp reads the power? do I need 3 separate clamps…(unable to do with the device)
I think you are missing trigonometry. If you put 3xL via one clamp you will get NIL as this is sum of 3x 120 degrees shifted sinusoid. Now, to be more exact, you may get something if phases are imbalanced but if you add N too, it will be NIL all the time. Exactly the same as for single phase putting L and N via single clamp. For what you made you’ll get the same result (turned 180 degrees) if you use single clamp on N only and leave 3xL alone. Neither make sense. Each L needs separate clamp and then it has to be calculated together.
figured as such.
it worked fine as testing on one circuit but when I used 3 different circuits it stuffed up. I basically figured to balance the load it was a different phase for each circuit and that was causing the issue.
thanks. will have to see what else I can do.