Mixing CT Amp Rating different legs of same circuit? - resolved


#1

Just a quick question which I think I know the answer too, but you guys are so much smarter.

Question: Can/or should one be able to mix differing amp rated CTs on the same 240v (one on each leg), or must you have the same on each if monitoring two?

The reason I asked is I have a free 200a (ECS24200) and an existing 100a (ECS16-100) CT on one leg of my barn circuit. I was wondering if I combined the inputs if this will throw things off or are the reading the same if the devices are made by the same manufacture? Momma always says it is best to ask when you do not know.


#2

You cannot combine them with the splitter if that’s the question. When combining, they all have to be the same. That said, you can feed them into two different inputs, configuring each as appropriate for the CT used, and then add the two inputs to get total watts on the 240V circuit.

It may be possible to muscle the barn cables to run them both through the ECS24200 as well.


#3

Thanks @overeasy and I assumed that would be the answer.

I’m not sure I would want to take up two feeds on the IoTaWatt for that one circuit, but I understand why it would cause an issue to combine them. I could see if the 200A CT would do the twist, but the cable for the circuit is not very flexible and quite thick; almost as big at the cables run for my mains to the house.