CT "scaled down measure" questions [RESOLVED]

Hi,

In the CT basics section of the documentation it says:

So without connecting anything directly to any high-voltage wiring, it’s possible to get a scaled down measure of the primary current that can be used to passively measure power (Watts) of a circuit.

I’m not 100% sure what is meant by that and it’s left me with a few questions:

  1. What is meant by “scaled down measure”?

  2. Are all readings displayed on the IOTAWatt scaled down?

  3. Do the readings need to be multiplied by a certain amount in order to show the true value?

  4. Is this only true for when the current goes above a certain level? ie. scaled down for anything >100A

Depending on the CT “turns ratio” the CT will output a current that is less than but proportional to the primary current of the circuit being measured.

No they are the computed actual Watts, Amps, Volts etc.

No, that is done by the IoTaWatt.

No, it’s fundamentally how it works.


It’s how all CT based energy meters work. Knowing the ratio of primary to secondary current, the IoTaWatt accurately computes the primary current.

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Thanks for the reply, I figured that it was handled by the IOTAWatt, but I had to double check.