PROBE BATTLE - PART 2: Expensive vs Cheap - AC test #2
TRAFOLO Magnetics - FEM Simulation Software
A specialized modeling tool for power electronics engineers who design magnetic components and test them virtually
Measuring DC is like watching a parked car - steady, predictable, and nothing exciting.
While AC - that’s like chasing a squirrel on caffeine! Signals jump around, frequencies shift, and not every probe is fast enough to keep up with the madness. This time, we crank up the challenge by testing each probe at 1 kHz, 5 kHz, and 10 kHz to see how well they handle the chaos of alternating current.
A quick side-by-side showdown of our fearless contenders - I-prober 520, Micsig CP2100B, and Micsig CP1003B - each competing at a different price point.
Smooth Sine Test
We start with a simple circuit to measure current, using a load to draw power from an amplified sine wave signal. This setup lets us see how well each probe tracks the actual current flow.
The Track They’re Racing On:
The referee is an Oscilloscope Siglent SDS1140X that will translate Volts into Amps.
All probes go head-to-head with a shunt resistor to see how far off their readings are. Will they stay within a reasonable error margin, or will some probes embarrass themselves?
All three contenders have crossed the finish line! ??
Next, we calculate the error by dividing measurement mismatch by true value (shunt).
The numbers speak for themselves:
Inductive Square Test
This newsletter is all about the measurement of real-world magnetics and circuits. It isn’t just about resistors and perfect signals. The real ones come with inductances and switches, making things a whole lot trickier.
Inductance loves to mess with current flow, distorting waveforms and causing unexpected oscillations. To put our probes to the test, we’re adding an inductive load to the setup.
Will they keep their accuracy intact, or will the extra complexity throw them off their game? Let's find out!
This time, we’ve raised the stakes by adding inductive and switching elements to the track, making the competition even more demanding!
We’ll test at 5 kHz and 10 kHz to see how these probes handle inductive loads. With the inductive load, the oscilloscope will show us the truth. Are the waveforms clean and accurate, or do we see distortion and lag? Let’s find out which probe stays sharp under pressure!
The probed waveforms are clean and precise, while the shunt shows distortion and lag - what a pitfall! Drop your guesses in the comments! ??
Here’s how the final results table looks:
The final remark
As you can see, we're dedicated to building a magnetics validation setup that not only helps us verify our simulations but also provides power electronics engineers with valuable feedback on the current waveforms they use in their own models.
If you appreciate our work, drop a comment with suggestions on what we might be missing and ideas for future topics!
Stay tuned - next time, we’ll dive into probe bandwidth with a high-speed sprint race for contestants!
Best,
Mr. Probe Mareks Kri?jānis
Mechanical Design Engineer | CAD and CFD Simulation | Mechanical Enthusiast
2 周Great post! I love the detailed comparison and the creative way you’ve presented the results. The inductive square test, in particular, caught my attention because it mirrors real-world challenges so well. One question I have: What specific factors could cause the shunt resistor to show jagged fluctuations during the inductive load test, as mentioned in the post?
PhD Power Electronic, HW/FW Generalist. Experienced with 2kW - 30kW design. Looking to grow power electronic RnD in Indonesia
2 周Your shunt resistor has its own parasitic inductance. So, the voltage measured across the shunt is actually V=i(sL+R). And if you are using the wire wound type, there will be double bummer. 1) higher L, 2) not insignificant parallel C