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Using CT output voltage

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I have CT SCT-013-000 100A:1V and i read the article about CT output current.


If I use the CT output voltage max is 1V, arduino read about 1.5v-3.5v, that so I can’t fully exploit the capabilities of 10bit analog of arduino.
So, how to scale up that.
Thank you very much!!

I do not understand. The c.t. maximum output voltage is not 1 V. In that circuit with those component values, it is approx 1.6 V rms. You will get that with 100 A rms flowing in the c.t. primary circuit.

Are you saying that your maximum current will be less than 100 A, therefore you need to increase the sensitivity of the input so that the Arduino input is 1.6 V (≈ 4.5 V peak to peak, to allow for component tolerances) at a lower current?

If yes, then you increase the value of the burden resistor (33 Ω). The maths are explained in the article, you must calculate the resistance that gives you approximately 1.6 V at the maximum current you want to measure, and remember the c.t. gives you 50 mA out for 100 A in the main cable.

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This is my c.t. 100A/1V, I think its max output is 1V*sqrt(2) peak-peak, the output is voltage, so i think I can’t use burden resistor. The burden resistor used as current 10mA(in c.t. output current) multi with resistor burden, result is voltage, I use Arduino ADC to read it.
But my c.t. output is voltage, I think I don’t need a burden resistor.
https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/interface-with-arduino

On my YHDC data sheet, the SCT-013-000 is 50 mA output, with no internal burden resistor.
The one you have is a SCT-013-000V

If you open the c.t., you will see two plastic clips holding the bobbin and the secondary winding in place. It is easy to spring those aside and pull the bottom half core and bobbin out. Inside, you’ll find a small p.c.b. You can unsolder the resistor (probably 22 Ω, labelled “220”) and then you can replace that with a higher valued resistor.

If you cannot do that, you need to buy a SCT-013-000.

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I have a module Voltage Sensor, output is AV 1V peak-peak, it’s work same SCT-013-000V, I don’t know how to increase scale voltage output.
Do you have any ideas?

I think it will not be possible to do that.

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