I'm struggling to design a circuit that will interpret signals from a SCT013 current transformer and trigger a constant 5v signal (which will go to a microcontroller) when a certain current threshold is met.
I thought I may be able to achieve this by taking the burdened AC signal from the CT and rectifying it with a bridge rectifier and smoothing capacitor. Then hook this up to the base of a transistor that will emit a 5v low current signal.
I thought that by adjusting the value of R2 I would be able to have the transistor 'trigger' at different current levels. The choice of transistor was arbitrary, I just wanted to see if I could get the rectified signal to 'trigger' the transistor. The CT produces a current between 0 and 50ma, its ratio is 1:2000. I would like the circuit to send a signal if the AC current is above 1 or 2 amps.
When I test this circuit there seems to be some problem with tying the bridge rectifier to ground.
I'm very new to circuit design and especially to using transistors, so I apologize in advance if this design is totally ridiculous. If it is, what would a more direct way be to achieve the same thing? I realize that I could hook the CT output up to a ADC on the microcontroller and just see if current is flowing that way. But I was interested in the challenge and I'd like to learn more about circuits and transistors.