Panel with subpanel and 2 devices

Hey there, I have 2 iotawatt devices pushing data from 2 panels. One is the main 200a panel and the second is a subpanel behind a 60a breaker off the main panel. I’m wondering if the subpanel device really needs to use two more CTs to monitor the mains as I already have 2 in the main panel. Also wondering if there is any risk with mixing and matching sensors across the two panels. I don’t see anything unexpected but wanted to ask just in case. Would also be great to use my 2 mains CTs in the second panel/device to monitor other lines if not needed on mains in the second panel. Thanks!

The sub panel feeds are not “mains” in the sense they do not monitor your grid supply. An IoTaWatt does not need to have mains CTs to work. So unless the total of all the circuits in the sub-panel is of interest and not all of the sub-panel circuits are monitored, you definitely can liberate those two CTs and employ them elsewhere.

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Awesome! Thanks for the quick reply and clarity; much appreciated!

Sorry 1 last question. Is there any real issue using an oversized CT for a smaller circuit? While the main clamp on CTs are good to 200amps, is there a noticeable loss of precision or other issues if it’s put on, say a 20 amp circuit pulling 5 amps? May as use the ones I have if I don’t actually need them on my mains…

The linearity is 0.5% of full scale, so that would translate to 4 times more than a 50A CT. But “noticeable” is a more subjective thing, and easier to determine, just clamp one along side a 50A on the circuit you are interested in and decide for yourself if it works as well or at least well enough.

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