Possible to purchase more current transformers from IoTaWatt?

1

I recently purchased an IoTaWatt 120V Kit which comes with the two 200A CT clamps. I also added two 100A clamps and 10 50A clamps to my order. The IoTaWatt is working great, allowing me to monitor my import/export of electricity on my mains, solar output, and the individual circuits account for about 90% of my home usage. I have it setup with Home Assistant to monitor my solar and home electricity use, and have more detailed data exported to Grafana using the InfluxDB exporter.

However, I’m currently forced to use two inputs for my Dryer circuit as it’s 120/240V. When operating, one leg uses 2700W and the other uses 3000W, so two CTs are needed to measure it. I would like to use a headphone splitter to have both CTs on a single IoTaWatt input. My understanding is that this will work as long as I use identical CT models and the CTs use opposite orientations to account for the opposite phase for each 120V leg in a split-phase system.

However, this will leave me with no more CT clamps. I checked online for AcuCT-H040-50 CTs but the best I could find was $22 + 18 shipping for a single CT on Amazon. On the AccuEnergy site, it’s $22 +$60 shipping since it ships from Canada. In addition to the high pricing, neither site appears to sell CTs terminated with a 3.5mm jack like IoTaWatt sells. The photos show 8’ of insulated black and white 26AWG wires, with the wire exposed at the end.

Is it possible to order additional CTs from IoTaWatt? I’m happy to pay shipping costs. If not, is there another source that sells the CTs at more competitive pricing terminated to 3.5mm jacks?

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the website shows these:

You can also just use one transformer and just use some math to split the difference. How accurate do you need to measurements to be? My dryer also has different loads on each leg. The motor runs all the time, and it’s 110, while the heating element turn on/off, at ~2000 watts. But I can measure it pretty close with just one leg.

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Thanks! That’s precisely what I wanted.

For some reason I couldn’t find that link myself. In the Uncategorized section, I only see the EChun 200A x 25mm clamp-on.

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You can use one 50A CT by passing both the red and black wires through it in opposite directions.

You can also buy additional CTs from the website.
image

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Haha, somehow I missed the Current Transformer dropdown. Sorry for the stupid question. As for passing both the wires through in opposite directions, there’s not enough slack in the wires to allow for that.

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Just ordered four more 50A CTs for future use. Thanks!