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Micsig Current Probe CP2100A/B Tests and Comparing

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Algasman:
One the voltage and current traces are properly aligned you can use the oscilloscopes math function to calculate power or energy

RobbiTobi:
You have to distinguish two facts:
1. the current probe has a physical signal delay, which is a constant delay as specified in the specs (here <150ns)
2. the phase-shift or phase-error is a function of frequency due to the signal processing chain (filters and more...)

You can compensate the constant signal delay i.e. by the CHskew setting of your scope - this is correct.
However, the phase-shift you can hardly compensate - only in the case you work with simple CW signals like a pure sinusoid.
As soon as you are dealing with complex signals like i.e. a square-wave you get a signal composed of harmonically related sinusoids with different frequencies (see Fourier series).
Your measured signal of the probe will get shifted and distorted due to the phase-shift error vs. frequency.
In that case you hardly can compensate the phase-shift of each sinusoid component and your procedure as described will not work anymore.

Noy:
You are right if you want to use it for power measurments. But even then you don't know is the Phase shift from your load or current clamp..
But if you use the clamp to verify current curves for example Motor/power supply switching current through inductor you don't have to care about Phase shift inside the clamp...

Would be interesting if Martins New Toy (other thread) has a phase shift / correction..

Algasman:
I tried to measure delay over frequency - unfortunately with the following restrictions/constraints:

Sinusodial Current of only 140mA Peak-Peak measured in 10A Range of current probe, therefore very noisy.
Proper measurement should be done with 1 to 5 Ampere signals, I don’t have a source for that.
Signals are 32x averaged
50 Ohm load resistor
Phase & Delay measurement with oscilloscope with high standard deviation on low frequencies due to noise.
Temperature also seems to have an effect on delay

I’d say this kind of test setup is only suitable for frequencies > 100kHz
The almost constant delay from 300kHz - 2MHz is impressive (bang for the buck)
The test equipment is the same as in my other posts

RobbiTobi:
Would be interesting to see how your probe works in reverse mode.
Just repeat your FRF and delay measurement with reverse current and see if the response is still the same... if the probe is well balanced.

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