Hi folks,
I would like to share some comments on the MicSig CP2100A&B current probes compared and discussed here.
First of all the CP2100A probe is a real bargain and good quality probe - I agree completely.
You all talk mainly about the bandwidth and FRF of the probes which are very similar for both (CP2100A&B) going up to approx. 3.5MHz.
That´s ok, but I am missing the focus on one important parameter of the probes here.
Just have a look at the phase-shift of these probes - this is more important than the max. bandwidth, i.m.h.o.
For what purpose you are using the current probe mainly? Probably, power/motor/switching testing applications.
So, measuring currents with a phase error of more than 10° will become critical for reliable power measurement and signal analysis.
In few words, these probes are only good for up to ~300kHz respectively - which is anyway quite impressive!
We have seen that both models (A&B) show a phase shift of 45° @ ~800kHz - upps, interesting due to the fact that the model A is marked 800kHz bandwidth.
My probe (A model) has a rise-time of about 100ns --> theoretical bandwidth of ~3.5MHz, however with phase-shift of ~5° @ 200kHz.
My personal assumption is that MicSig started this product by designing the A model first with "realistic specs".
And for marketing/sales reasons with the help of binning on cascaded filters "created" an "upgrade" for making money, but not really useful as the phase error is completely "out of order" above 800kHz.
Concluding, i.m.h.o the B model is not worth its money - just stay on the A model.
Cheers!
P.S.:
By the way, I suppose you all have checked the UT210E modifications made by Joe Smith years ago - great job Joe!
However, by changing few resistors only you can achieve a low-cost probe with a bandwidth of ~20kHz@2A and ~100kHz@20A - impressive current probe for some basic tasks!
Find a simple testing comparison with the CP2100A attached.