Double check my CT assignments?

I was hoping to get a double-check on this equipment list. US, 200A service. The heat pump has an inverter driven compressor.

Probably somewhat obvious but everything except the last 2 lines are 240V:


and here’s my panel:

The dryer I’m not 100% certain I’ll be able to get both through with one reversed…but the oven has that nice extra loop of wire just like in the docs so I know that one will work. I’m not even gonna try on the sub-panel.

Thanks for guidance, just want to be ready when the base units get back in stock.

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Your list is a little confusing. You are mixing some loads into one line (solar, heat pump ones) and calling others out in two (main and several others).

For loads that are true 240V and don’t use the neutral, you only need a single CT and only need to run one of the two wires through it. There is an option in IotaWatt to double the value, which is what you would need to do.

For the loads that are 120/240V, like the dryer and sub panel, you can do the reverse one wire trick or you can use 2 CTs and combine the output. I use headphone doublers or just connect the wires together for my CTs that don’t have plugs. The CTs are reasonably priced. 8ga and larger wire is fairly stiff. It might be harder than you imagine to bend it the right way to put two wires in one CT. I would suggest trying it on some scrap. You can frequently buy it by the foot at home improvement stores. So buy several feet and see how hard it is to bend. Then try it in a confined space. Even $10-15 extra per bend I didn’t need to do seemed worth it.

14ga wire is much easier to manage, but make sure you know which direction the wires need to go if you put two together.

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I thought I understood everything after reading the docs a few times and reading over forum posts. Can you point out specifically what you think is wrong with what I have? It’s certainly possible I am misunderstanding.

Everything except the ones that say 3 wire are “pure” 240V which should only require one CT and checking double on the input (obviously except the 2 mains).

I have 3 loads that I wanted to monitor that are 240+neutral (“3 wires”)…the subpanel which I allocated 2 CTs and 2 inputs to so that one is easy and then the dryer and oven. The oven has the extra loop of wire just as pictured in the docs so there should be no trouble getting both wires through with the one reversed. The dryer is the only one that I am questioning being able to get 2 wires with one reversed through and if it doesn’t work out that’s fine. I believe the dryer circuit should be 10# wire for the 30A circuit (orange romex?) and that’s the thickest one I’m going to need to “bend”.

It sounds like you have thought it through well and I agree it makes sense. Your table didn’t make as much sense to me at first, but does now that you explained your thinking.

I also wondered why an air handler would need a double 100A breaker. The air handler doesn’t, but the strip heater inside it certainly does. You definitely want to figure out what you need to do to keep that from coming on.

No worries…that’s why I asked in the first place, making sure my assumptions were valid.

Yep, I’ve got 15kw of strips in there but the air handler has 2 breakers and it’s split 10kw and 5kw with the 5 off “unless we need it”. I think the “main” breaker on the AH is 60a. The panel breaker was 100A from the old system and it was left that way, I’m sure it’s a bit oversized for the true load now. I was thinking of asking the installer to swap it around and only have 5kw be available under normal circumstances and have the 10kw turned off normally. Once it gets real cold we burn wood for heat and stop using the heat pump but it’s nice to know it’s there if we need it. I learned a lot over the last year about heat pumps and thought locking out the aux heat via the thermostat (ecobee) was enough and didn’t realize it used the strips during defrost which the stat doesn’t show you/tell you is happening but your electrical meter certainly will.

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