CR Magnetics CR 3110-3000 have TVS diode?

1

I have a bunch of CR Magnetics CR 3110-3000 CT sensors and it looks like they do not have built-in TVS diodes and I haven’t been able to find a schematic of a Echun ECS 1050 to compare. Here is the link to the schematic for a CR 3110-3000: https://www.crmagnetics.com/Assets/ProductPDFs/CR3100.pdf
Also, do the wires have to be shielded, or enclosed in sheathing?

Thanks for any help offered

2

I have some CR 3110 CTs. They do not have internal TVS diodes.

They do not require shielding, but there may be codes that apply to the leads when used in various environments. The eChun and AcuCTs have leads rated for 300V and 80°C, which is stamped right on the wire and should comply with most codes when used inside an electrical box.

You probably are aware of this but FBO anyone else reading this, TVS diodes are not needed for the IoTaWatt to work properly. They are there to protect the CT against damage in the event it is unplugged from the IoTaWatt while the primary load is active.

I installed CTs in my panel years ago, before starting to import eChun or AccuCTs. As a result, I have an eclectic collection of CTs:

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I’ve never bothered to change them under the “If it ain’t broke don’t fix it” rule. (I do have eChun CTs in several other installations). You can see that I use CR3110 CTs, but I did install TVS diodes into the cords so That I could unplug them (as I have over the years) with impunity.

3

Can you share a schematic and TVS diode part number for the CR 3110-3000 retrofit?

4

Sorry, I don’t have that info anymore. Any bi-directional TVS diode should work. You install it between the two leads.