CT Cord Extension

I have everything set up in my breaker panel. However I, just realized the AC breaker is in separate panel outside on the brick wall. I need a CT with a cord length of 50 ft or more . Do you know where I can purchase one or do yall sell something like this?

Unless there are other things connected to the mains upstream of your panel, you connect the mains CTs to the mains cables where they enter your panel. Do you have a photo of the panel?

Fifty feet is getting to the limits, but I cover extensions here:

Outside panel runs the ac unit outside and does not go through my inside breaker panel

Inside panel has a 20 A single breaker that feeds the attic portion of the AC, the blowers. But I need the two breakers in the outside panel (double 40 A) that feed the condenser that’s outside to measure the total amount my AC unit draws

There are a few issues here:

The actual mains are buss-bars coming from the meter to the breaker sockets. They don’t look easy to get a CT around.

Where would you run the extension? I don’t know if it would be allowed inside the conduit with the main, but that’s probably not a good idea at that length because of possible noise.

The basic problem is that the AC compressors are not being measured. You have the 100A main measured in the main panel. So you need to capture the AC only. How far is it to the actual AC units, and is there a viable way to wire to those? Usually there are control wires running to them, can you run a wire along that path?

If so, or even if you are going to go for the meter box, those are two-wire 240V, so each one can be measured with one CT, or… you can measure both with a single 100A CT around either both black or both black/red cables. Run that back to a single IoTaWatt input. If shorter, try to do it at the AC compressor.

The Compressor breaker feeds a line up the wall into the attic where it travels for about 4 ft then goes down same wall to the compressor outside. I was going to install a junction box for that line in attic and install the cts in that. That would put me around 20 ft from the iotawatt input.

The bus bars outside I’m not worried about. If I get the compressor along with the mains in my inside panel, I’ll have what I need

Does that sound viable?

Yes it does. Wherever you can conveniently get at the compressor lines as close as practical to the IoTaWatt. Someplace that conduit from the meter box splits to go to the panel with the mains and to the compressors.

Edit: I see one is marked OVEN. So probably need to put separate CTs. The good news is that you only need 50A CTs which might fit in an existing conduit hub.

If I just reran the compressor to my inside panel by adding a double 40 a breaker, would my panel support that or is that overload?

You would need to hire a licensed electrician for that type of work. And, most likely the wiring from the Main Panel (outside) to the Sub Panel (inside) is not capable of carrying all of that current, as you’d need to increase the breaker size in the Main Panel to accommodate both the AC compressor + the entire Sub Panel (from 100A to >140A).

Also, I would recommend moving the IoTaWatt out of the Sub Panel into its own plastic electrical enclosure. That Sub Panel is looking a little scary with all the IoTaWatt hardware and wiring jammed into the bottom of the panel. Also, the WiFi signal is going to be challenged by having it inside a metal electrical panel.

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@ogiewon is giving good advice about getting the IoTaWatt out of the panel. Underneath the pile of wires are three exposed circuit breaker contacts. The potential between any two adjacent is 240V, just like the mains lugs. That is definitely not a safe situation.

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