Determining if a CT is defective or broken? - RESOLVED

I am just getting to install my first iotawatt I bought over 1 year ago. I installed two ECS24200 CT on my split-main legs. My issue is that one of these CTs is not being registered by IotaWatt, meaning no information is coming from the channel when that CT is plugged in to it, as determined by looking at the Status screen. The configurations are identical and I’ve tried swapping input channels and positions without success as well as configuring a 3rd channel. The other CT shows data on the Status screen as expected. How can I assess if this CT is working or broken? Is it possible I received a defective CT?


If i understand what you ar3 saying, you have the two CTs plugged into inputs (say 1 and 2) and one of them is reading something on the status display and the other is zero. When you swap the two plugs, the zero value moves to the other channel? If you move the zero reading CT to the same mains cable as the other (if there is room), does it still read zero?

All that being true, you can send the CT back. I’ll test it and fix or replace. I would need your original order number.

IoTaWatt inc.
PO Box 1679
Wolfeboro, NH 03894

I’ve never had one of these DOA before, so I am curious what is going on here.

Thanks for the response.

Thank you for the testing suggestions. What you ask is what I’ve tried…
CT#A on Black Leg -> Input 1 = reading on the status display, e.g. 418 Watts, pf: 0.82
CT#B on Red Leg -> Input 2 = 0 Watts

CT#A on Black Leg -> Input 2 = reading, eg 512 Watts, pf: 0.92
CT#B on Red Leg -> Input 1 = 0 Watts

CT#A on Black leg -> Input 2 = reading, e.g. 300 Watts…
CT#B on Black leg -> Input 1 or Input 3 = 0 Watts

Inputs 1, 2 and 3 all configured the same.

The only physical difference between the two CTs I can perceive is that CT “B” plug is slightly less resistant when plugging in to an input jack as compared to plugging in CT “A”.

Based on your response I’ll send it back, thank you. My order number is #1039. I need to order a few more CTs, in addition to the ones I ordered a few days ago, so perhaps that all can be combined.

Thank you

Just to close this thread, it turns out the 3.5mm jack of the misbehaving CT had a little extra insulation around it, preventing it from plugging in all the way. The trimmed up jack now plugs in all way and the CT is working as expected. I appreciate the help and product support.