Does the quality of current transformers matter?

Question

I would like to do some current sensing, i would like to know if cheap current transformers like the the SCT-013s as good as abit more pricier onnes on digikey, what should stop me from making my own? The SCT-013 are already relatively cheap but i can go even further and ordering a core and winding some magnet wire on it (it might be tiring to wind so many turns but its cheap).

One of the reason that some might be expensive is because of the built in amplifier i understand that, but if what if i already have those on my adc front end, even the burden resistor, and just want the coil. I could not think of a possible downside since there are very few parts, a core and a wire.

Answer 1

Does dynamic range, effective turns ratio from loses, rise time, bandwidth, DCR, linearity, phase shift error and temperature error of magnetic material matter?

Yes of course quality matters and your specs matter the most to determine if it is possible to meet your expectations for the application.

• one used for 50 MHz 50 Ohm is far different than one for 50 Hz. What should stop you from making your own?

• A lot of experience is necessary for choosing from the vast array of magnetic material properties and winding ratios with saturation currents, excitation voltages and choice of high mu with an air gap or low mu with more distributed magnetic particles etc.

Reading lots of reports and knowing how to test these current sources is a learning experience that should never be underestimated. When you understand what matters write a good spec then go shopping. Maybe you end up with 3 current sensors , one with nano particles and one with silicon steel and another with a Kelvin 50mV bridge.