Best clip on CT's for IoTaWatt on a UK Dist Panel

Hi All, I’m new to the power monitoring game. Just about to get a solar PV installation with battery storage and I’d like to get a better view on our usage, where that power is coming from (solar, battery or grid), and how well the solar kit is perfrorming.
I think the IoTaWatt will suit my needs.
The circuits I want to monitor are:
Main in 100A
Cooker 40
Ring Main 32A x 3
Lighting 6A x 3
Water Heater 40A
Solar Feed ?

My question is what CT’s are best for my purposes and where to get them from.
Any guidance appreciated.

Welcome Clive!

I’ve found that the CTs that are available on the IotaWatt website are pretty good, and are slightly more compact than the YHDC ones on the Open Energy Monitor shop (and elsewhere).

It’s not worth worrying about the rating of the CT too much between (for example) 20A, 30A and 50A, because the cheap ones are all the same physical size, and the sensitivity isn’t much different. Just pick one 100A CT for each consumer unit or on the consumer tails, and a 50A per circuit for monitoring.

I tried to cheap-out and get my CTs separate from the base kit, and I wish I’d just got enough in one go. Either that, or got some of the tiny solid-core ones, and had the electrician fit them with the solar system, but then you can’t play with them much to double-check accuracy.

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Thanks Tom.

Out of interest where would you source solid core CT’s? I may be better going down that route.
I’m either getting too old or going daft as I can’t find a link to them anywhere either on here or on IoTaWatt :wink:

Might be better asking on the Iotawatt forum!

I’m not an expert, but something like this:

It doesn’t have a TVS diode, it’s got quite a slender bore, and it’s just a bare flying lead, but it’s a starter for 10…

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Here’s a UK source. Locsted in Wales IIRC.

From the page at the link above:

They sell split-core CTs as well.