EEVblog 1413 - Oscilloscope Current Probe TEARDOWN + DEMO

Рет қаралды 45,871

Күн бұрын

Teardown and measurements with the Micsig CP2100B 2.5MHz oscilloscope current probe.
Also a demonstration of mains switch mode power supply current and noise measurement, and also some performance tests.
Use the coupon code FLUX for 15% off!
And paying with crypto gets you a further discount on top of that!
www.eevblog.com/product/cp2100b/
Or get the cheaper lower bandwidth 800KHz CP2100A model:
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Oscilloscope standard deviation measurement: • EEVblog #1223 - Oscill...
00:00 - Intro
05:39 - Teardown of base unit
14:25 - Clamp unit teardown
23:40 - Mains switchmode current measurement
34:00 - Measuring the Earth's magnetic field!
34:42 - Noise measurement
35:26 - Low current measurement
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#ElectronicsCreators #Teardown #Review

Пікірлер: 138

@yuxianwang3238 2 жыл бұрын

Well this is widely used in current sensing for hall sensor in parallel to cancel temperature coefficient. And I work for the company in the video. Max bandwidth we have now is 1-2mhz. And this not yet publicly available.

@npc6632 2 жыл бұрын

You work for Micsig?

@yuxianwang3238 2 жыл бұрын

@@npc6632 multidimensional

@npc6632 2 жыл бұрын

@@yuxianwang3238 So it is a Multidimentional device in the Micsig?

@yuxianwang3238 2 жыл бұрын

@@npc6632 I’ll double check that. It might. But looking at the design. The ferrite core should not have a bandwidth of 1mhz. The magnetic permeability drops dramatically at high frequency. For those material. The best I known of caps at about 2mhz.

@HighestRank 2 жыл бұрын

@@npc6632 Multidimensional *

@voltlog 2 жыл бұрын

The micsig probe beats the others on specs vs Price and build quality and I've been a happy user for a while now. Anyone doing these kind of measurements should get one!

@dnbeuf72 2 жыл бұрын

Got it myself as well. Quite happy with it so far. For measuring low currents a wire can be passed multiple times through the clamp to increase sensitivity. Looping twice makes current readout twice as high, .. etc

@1kreature 2 жыл бұрын

The USB DC-DC is to isolate the supply from your oscilloscope. Very good!

@integra1979 2 жыл бұрын

I was thinking the same thing, Or when powering it with other usb power source

@andrelange9877 2 жыл бұрын

It is for preventing a ground loop between your scopes USB ground and BNC ground.

2 жыл бұрын

I dissected the PROVA CM05 current probe, and it also had two sensors mounted in opposite direction, and electrically chained in the same fashion.

@jenniferwhitewolf3784 2 жыл бұрын

For decades I have used the Tektronix A6302 current probe (50MHz) with AM503 module. It is an amazing tool as a design aid when designing power supplies. I would not even think about designing a supply without being able to actually see such things as the transient current on the peak of voltage haversine charging filter capacitors. If you are even thinking of designing a power supply, first buy a current probe. This is an affordable and decent performing tool. Every lab needs one.

@TheDigitalAura 2 жыл бұрын

Micsig seem to make some pretty good stuff, very happy with the 100mhz differential probes I bought.

@messingwithelectronics7462 2 жыл бұрын

Agreed, I also have the diff probes and the quality is crazy for the price.

@EEVblog 2 жыл бұрын

I had them design a x10/x100 model and I was going to stock it, but it had an issue with CMRR whne I measured it. They are coming out with an updated design.

@AHaensel 2 жыл бұрын

"I haven't personally gone over 10 amps" - I think Photonicinduction may be able to help...

@rubusroo68 2 жыл бұрын

Really nice build quality too. Another great device I have absolutely no need for but will probably end up buying.

@robinbrowne5419 2 жыл бұрын

It would be interesting to put the mains current on channel A, and the main voltage on channel B. Then multiply them with the scope maths to get the real power.

@ulfg1409 2 жыл бұрын

If you put it around the feed wire to the starter motor on a small multi cylinder engine (100A isn't enough for large engines), a motorcycle for example, and disable fuel or spark so the engine doesn't start you can do a relative compression test in seconds. The current goes up as the starter works against the compression in each cylinder, so you can determine if all cylinders are even or one has lower compression than the others. Use it on any other brushed electric motor (such as a fuel pump) and you can see the current variation as the segments on the commutator rotates past the brushes, if brushes/segments are bad or a winding is toast it will be quite uneven while a good one should basically be a nice wave repetition. You can see if an electromagnet moves something, as in a relay or fuel injector, the movement gives a hump in the current waveform. You can identify coils (relay, fuel injector, ignition coils and so on) with partially shorted windings, as the current waveform will be different from a good coil. A current clamp can be a fantastic diagnostic tool, even with far less bandwidth than a great one like this. I really have to get one soon - or a couple, for low & high current.

@robbieaussievic 2 жыл бұрын

..... How cool, diagnostic detail surpassing mechanical results.

@marcelhensen6847 2 жыл бұрын

You need to hold the probe in the orientations it's going to be during the measurement as you are zeroing it. Otherwise you don't compensate for the earth's magnetic field.

@supernumex 2 жыл бұрын

Yup. Best to just set up your probe around the wire, power down everything, zero, then measure.

@WarpRadio 2 жыл бұрын

don't forget: tongue at the right angle and virgins on the slab, as well! :)

@davidjereb 2 жыл бұрын

7:46 Having used an EFM8 chip before in a precision analog application, I strongly disagree. The internal ADC is as stable as a rock.

@wearethewatt2950 2 жыл бұрын

Dave, if your result is 42 then you dont need to regard fractional digits. Those are errors by definition as the exact answer is known.

@robbieaussievic 2 жыл бұрын

...... And the answer to 'Life, the universe, and everything'.

@circuitblog01 2 жыл бұрын

Very nice video Thanks for posting

@MikelNaUsaCom 2 жыл бұрын

In college, I worked on a battery powered pic micro-controlled 3 phase current monitor that turned on, took a reading then went back to sleep ... used a i2c dac and 3 external probes, ic2 memory. auto calibrate, set in the box, lock it up, come back in a few weeks and download the memory using RS232 to a pc and use excel for data analysis... bob's ur uncle. Great memories.

@casperhito 2 жыл бұрын

Dave makes infomercials fun. Good on ya

@johnnyjoseph1389 2 жыл бұрын

I use the A version of this and Micsigs ATO1104 automotive scope... Both are surprisingly well made and surprisingly inexpensive when compared to the stuff you buy off the tool trucks in the automotive industry.

@user-dr3ol1jo8c 5 ай бұрын

HI Dave, a couple thoughts for reviewing AC/DC current probes: it'd be helpful to examine the AC waveform phase shift across the bandwidth, and square wave replication accuracy across both the current ranges and frequency bandwidth - it can be helpful to be aware of these things when using a current probe in brushless motor or switching power supply circuit analysis.

@justin.campbell 2 жыл бұрын

The coax going into the shielded box looks like its close to shorting onto that cap!

@KG4JYS 2 жыл бұрын

It's more like $510USD plus shipping with the coupon code. Hantek makes one that's not nearly as nice, but it's $54USD. Manual zeroing and 20khz limit. That's fine for what I bought it for. Those of us that have an entry level scope like a ds1054z probably balk at a probe that costs more than the scope.

@amrishhirani6096 2 жыл бұрын

Nice and best Thanks 👍

@N2Stooges 2 жыл бұрын

Starting at around 37:45, did it seem like the scope waveform was reacting to Dave's voice?

@davidbi9765 2 жыл бұрын

I'm guessing the isolated DC-DC converter was used, due to most benchtop osciloscopes having an earthed probe ground, which could cause problems with some power supplies.

@EEVblog 2 жыл бұрын

Right. If you powered from another USB source that could be potentially problematic.

@User3578742267 2 жыл бұрын

Yes. And making two rails from one by single dc-dc.

@andrelange9877 2 жыл бұрын

They may also think that bridging the USB ground to the BNC ground through signal cables is a bad idea noise wise. The isolated conveter breaks this potential ground loop.

@mxzhang8836 2 жыл бұрын

The PSZQ is TPS7A30 low noise negative LDO

@alessandroscroccaro1424 2 жыл бұрын

I own the CP2100B micsig and I confirm that the bw -3dB reaches more than 2MHz (I measured the band) then the capacitive couplings weigh and therefore it is difficult to appreciate, but still a great result under 400 €.

@wastelandwanderer3883 2 жыл бұрын

Coming up next: A video on past probes!

@AlexLoVecchio 2 жыл бұрын

The Hall effect sensors might be polarized, hence the 180 degree offset. Remember that the current might be flowing one way or another through that core, reversing the magnetic field.

@EEVblog 2 жыл бұрын

The single sensor is likely already bidirectional.

@jansmit4628 2 жыл бұрын

12:15 The soldered centre line of the black coax is really close on top of the capacitor with marking C66 to it.

@mlenstra 2 жыл бұрын

I’m guessing there is quite some separation between them in height. Would’ve been cleaner if they kept the area under the coax clear and/or applied some hot glue to keep things from moving around though.

@IvesvanderFlaas 2 жыл бұрын

"If you go over the 100A limit you won't break it" - are you sure about that? I used to think so until we blew up some LEM sensors due to overcurrent. Admittedly, this was in a short condition with probably tens of thousands of amps, maybe more, still.

@byronwatkins2565 2 жыл бұрын

Magnetoresistance is proportional to B^2 and thus is not directional. Resistance does respond to temperature changes, however. To measure polarity it is necessary to establish a constant Flux midrange. Perhaps the two sensors are for the two ranges? Or possibly for temperature cancellation.

@smunaut 2 жыл бұрын

USB power would cause a ground loop that could pickup stuff without the DC/DC isolation.

@falkkyburz 2 жыл бұрын

Small clarification at 30:50: The current we are pointing at is most probably the X capacitor current which leads the voltage by 90°. Current to achieve PF~=1 would have to be in phase with the voltage (which we don't see). Even with a PFC, the X capacitor would mess up the PF with the added capacitive current.

@udhayakumara4033 2 жыл бұрын

I was waiting for this review for a very long. You showed this probe in one of your old video. Planning to purchase one for me. Surprisingly India is not available to select in country list. I sent an Email to you regarding this unfortunately there was no reply. You must include India.

@lordjaashin 2 жыл бұрын

india is often not included because of so many scam call centers based in india and the sky high custom taxes for import electronic stuff.

@EEVblog 2 жыл бұрын

DHL limitations IIRC

@beardedgaming3741 2 жыл бұрын

ive got a less smart version of this on my multimeter as well, it goes to 4000A i believe

@bgdwiepp 2 жыл бұрын

I think these may not be "hall effect sensors" but rather, they may actually be discrete hall elements similar to those that AKM produce (www.akm.com/eu/en/products/magnetic-sensor/hall-element/ some even suggest use in current clamp meters lol). Hall elements are at the heart of all of the different hall effect sensors, they are what produces the measurable quantities from the magnetic field. Why do i think this? Hall elements have high output resistances and small output voltages, a perfect application for a instrumentation amplifier, using a pair of them differentially means the temperature drift cancels but the sensitivity doubles. There are no bandwidth specs for AKMs hall elements, but I know AKM are an industry leader in current sensor ICs with the highest bandwidth and lowest response times, so I assume their hall elements would be in the same boat.

@calholli 9 ай бұрын

It's weird seeing this thing have a little 12bit ADC built in, because I'm fairly sure that all Micsig's tablet scopes are only 8bit.

@SoundsLikeOdie 2 жыл бұрын

I was watching a DIY probe build and they used a op amp to offset the DC reading from the hall effect sensor. I would guess the reason for the back to back sensors would be for reversed DC current. On a side note. I absolutley hate the buttons used. They should have used microswitchs. In surprised you didn't say anything.

@darrylgodfrey9604 Жыл бұрын

After dithering for some time, I finally bit the bullet and bought the 'B' model. Can anyone enlighten me about the use of the manual up/down switches? Perhaps they're useful if the auto-zero keeps failing? Secondly, a few contributors talk about the "ferrite" core. I'm still learning about the weird and wonderful world of magnetics, but that core looks like plain ol' laminations to me, not ferrite (which is a ceramic). Am I mistaken? Thanks again, Dave. I've been putting off buying a current probe for some time due to the crazy cost, but this one looks like brilliant value for money.

@Equiluxe1 2 жыл бұрын

Do they reverse the hall sensors so that it indicates polarity, the current probe I have does that and its only a cheap one.

@PlasmaHH 2 жыл бұрын

Since they seem to shift the ground, is that maybe the reason to use isolation on the power supply?

@mc_cpu 2 жыл бұрын

Unfortunately it costs more than my scope did!

@black56night 2 жыл бұрын

Your FLUX discount here says 15%, yet applying it on your website results in $15. So which is it?

@EEVblog 2 жыл бұрын

Oops, fixed now. it's 15%

@TonyLing 2 жыл бұрын

What sort of CT is used with that Voltec? The ones I use with mine don't work

@5mxg 2 жыл бұрын

@34min I wonder if those are parasistics mains. the trigger line is goin up, so its not a dc signal ?

@uzaiyaro 2 жыл бұрын

I wonder if you can just solder a recycled USB cable in and make the ports pass data?

@dangerotterisrea 2 жыл бұрын

Remington! Sadly missed 😆

@OC35 2 жыл бұрын

Victor Kermit Kiam II

@kwpctek9190 2 жыл бұрын

Re-badge this if it's good. Hey, was that 10ma signal scope averaged? At 12-bit resolution, wouldn't that uC's AD/C have a tough time? LSB works out to a paltry 2.5ma, so we were watching 2 bits... Did I miss something?

@EEVblog 2 жыл бұрын

The output is completely analog, nothing to do with the ADC or DAC. The DAC just shifts the DC level.

@lmt200ish 2 жыл бұрын

Hi, not sure if you would do this but I would like to know more about flameproof or fuse resistors? Are they the same thing reading the bands if that is the same, identifying them. There really isn't much on youtube for info. Thanks

@user-dm1nf3lz4i 2 жыл бұрын

keep going 812k

@cold3lectric 2 жыл бұрын

Helpful, thanks! I'm hooking up a Pintek Pa-677 current probe (clone of Rigol RP1002C) to a Rigol DS1054z scope - I'm stuck on a noob issue, translating the Probe "Scale" to the Scope's Channel scale/ratio setting. Is 50 mV/A to equal 0.05x, and 500 mV/A being 0.5x? Or should 500 mV/A probe scale be 2x on the scope channel setting (thus 50mV/A would instead be 20x)? Is there a snappy rule of thumb or logical expression of "how one knows"? Thnx if anybody can chime in

@kmundendy660 2 жыл бұрын

thank you Sir for sharing. I am considering buying a current prob with an eye on micsig CP2100a/CP2100B . Any suggestion please?

@ebones6957 2 жыл бұрын

Where would you need 2 MHz response at 100A?

@davecook2428 2 жыл бұрын

Newby question, when the bandwidth is stated at 2.5 MHz, does that mean that the instrument will report accurate recent measuring samples to the oscilloscope at 2.5 MHz and should only read waveforms with frequencies are some fraction of that, say 250 kHz (if 10 samples per period is enough?), or is it stating the device should be accurate enough to measure waveforms whose fundamental frequency is 2.5 MHz?

@petergamache5368 2 жыл бұрын

The bandwidth stated on most scope input devices is -3dB ... so at the "rated" frequencies, you'll already be seeing some drop-off. If you intend to regularly look at signals of a certain frequency, give yourself some headroom when selecting a probe.

@davecook2428 2 жыл бұрын

@@petergamache5368 Thanks for commenting Peter, but my main question is more basic, I'm not sure what the bandwidth is stating or asking a different way, what waveform fundamental frequency is a device with a 2.5 MHz bandwidth good for. Should a 2.5 MHz instrument be capable of visualizing sine waves at 2.5 MHz, of will it be limited to a lower frequency that has to accommodate so many points per wave period. If its recommended that 100 point per period will give an adequate reading, then this 2.5 MHz device would be recommended for waveforms less than 25kHz? If I'm only interested in visualizing the basic waveform shapes and frequency, how high a sine wave frequency are the 2.5MHz and 900kHz current sensors good for?

@jaxjackson4100 2 жыл бұрын

Dave, wouldn't it make sense to have two sensors in opposite direction for the AC current?

@EEVblog 2 жыл бұрын

The single sensor is likely already bidirectional.

@nixxonnor 2 жыл бұрын

If 20 kHz is enough, from 50 mA and up to 40 A you could also get the cheaper Hantek CC-65 presented here: kzfaq.info/get/bejne/hNNmmLCHzLvVYIU.html and teardown: kzfaq.info/get/bejne/nc2YnNup2sWyc2w.html

@waterfuel 2 жыл бұрын

Is 6 amps AVERAGE DC current on hand held multi-meter, or panel meter,, the same as PEAK 6 DC amps on oscilloscope? I thought it was a 60% difference.

@matthewswords 2 жыл бұрын

I'd love it if I could bring this guy to my work to see the toys we have

@HighestRank 2 жыл бұрын

“deckle” 5:44

@shazam6274 2 жыл бұрын

Dave, say "Dee Kal" or I'll hit you with this Al-you-min-eeyum" coloured bat.

@JmanNo42 2 жыл бұрын

How would one build something to measure changes in direction and amplitude of earths magnetic field, does it oscillate? Is there any cheap tools to visualise it, maybe computer kit? Android app? Yeah i know about compass ;)

@JmanNo42 2 жыл бұрын

Is there something like Schumann resonance meters? Could it possibly tell something about the weather?

@ElectricGears 2 жыл бұрын

You would take 3 of the hall effect sensor and arrange them orthogonality and fix them to the Earth. Connect them to a microcontroller and it can to the basic trigonometry that would give you a vector of the Earth's magnetic field. You could log it for as long as you want to look for changes or patterns that correspond to weather patters. Single chip 3D magnetometers already exist and I believe many smart phones have them. www.digikey.com/en/product-highlight/m/melexis/mlx90392-3d-magnetometer They provide the compass heading and are a stabilizing reference to their 3D accelerometers. I don't know if Android or IOS exposes the actual vector to apps, but if they do than you could make an app. I don't know about the accuracy since the field strength is very low already and the changes would be very small. The sensor is already inside the phone which would be a source of shielding and interference.

@JmanNo42 2 жыл бұрын

@@ElectricGears A compass do reasonly well "with direction" indoors, would there be problem with all electric gadgets for electronic sensors? Could any of the gears you descirbe above measure amplitude/strength with any precision i understand 30 micro Teslas? is a very weak field? I would love my computer/phone to measure it at least within a magnitude of its normal value and plot over time, you think it could be achieved by some easy mean? This seem to measure micro Teslas, but does it work or just a toy? www.banggood.com/MUSTOOL-MT525-Electromagnetic-Radiation-Tester-Electric-Field-and-Magnetic-Field-p-1276997.html?cur_warehouse=CN&rmmds=search

@JmanNo42 2 жыл бұрын

My phone had no sensor....

@EEVblog 2 жыл бұрын

Not easy to avoid it. If you are desinging to measure small magnetics fields it's kinda hard to avoid the big one surrounding everything.

@varunsingh.varunsingh 2 жыл бұрын

I always feel envy when you get this lovely stuffs to reverse engineer...🤠

@4dirt2racer0 2 жыл бұрын

around 24:28 u mentioned how u were plugged in via usb, but then u said "no wackas" lol why did u say that does it mean somethin like "no weird shit" or "no fakery" ? i feel like thats not right lol

@black56night 2 жыл бұрын

Silver medal.

@beardedgaming3741 2 жыл бұрын

i use micro versions of this (hall effect) on electric cars for factory integration. sniffing the can bus and programing triggers for aftermarket devices from factory hex data. the newer cars all have advanced current protection circuits so if they get an over the air firmware update and while flashing they detect some spliced in device thats drawing even a few hundred mA more than spec they can hard stop... bricking a dozen computers in a 100K$ car. only fix is to remove the offending hardware, remove the computers and side load them with new firmware... it fucking sucks. so by passively reading data bus and drawing power from discrete 12V sources, you eliminate this scenario.

@Roseworthy39 2 жыл бұрын

Dave, Please help: I ordered and paid (PayPal) for one of your CP2100B probes nearly 3 weeks ago (Fri 20th Aug). Other than the original PayPal message, I have heard nothing. I understand supply problems at the moment, but can you please confirm that my order is progressing? Really keen to hear from you. Regards, Charles.

@Roseworthy39 2 жыл бұрын

Thanks for your response, Dave. All received OK. Rgds, Charles.

@firedeveloper 2 жыл бұрын

is anything wrong with the camera? it looks like phone camera and low bitrate 4:34 the moment the clamp close everything blurs out

@npc6632 2 жыл бұрын

Seems ok to me?

@kitecattestecke2303 2 жыл бұрын

Nope. Phone is broken :-)

@user-dj1hy6zc6q 2 жыл бұрын

Seems like something is wrong with the internet connection between you and the KZfaq server.

@0x8badf00d 2 жыл бұрын

I can see that too. Not exactly blurry, but the video quality drops.

@IanScottJohnston 2 жыл бұрын

1080p start to finish here in the UK.

@JesusisJesus 2 жыл бұрын

Dave sold his ass. Do I get free steak knives? This does not help anyone who doesn’t work at a desk.

@captshae 2 жыл бұрын

Out of stock

@muppetpaster 2 жыл бұрын

Oh wow....youcan put it OVER your cable? That's genius.....Never thought about that....never seen it .....Is that a new concept?? LOL....

@muppetpaster 2 жыл бұрын

And yet I paid 230 $

@Solron78 2 жыл бұрын

00:29:43 LOL!!! Illuminati confirmed!! /jk

@itchynads4585 2 жыл бұрын

Thank god something non political.

@stuartcornall5306 2 жыл бұрын

2nd

@hughsgarbagetrucks 2 жыл бұрын

🥉

@WarpRadio 2 жыл бұрын

I have to say.. the COAX connections are ATROCIOUS! they aren't even RF GRADE (the stem becomes an INDUCTOR at the higher frequencies) Why doesn't anyone seem to know HOW to "unbraid" a coax? perhaps I should do a DEMO VIDEO and teach everyone how to do it.. I mean, not even radio/RF guys (and, even, hams) seem to now how to do this (I'm been able to do it since I was 10 years old, for crying out loud hehe) Oh, WAIT! he did say this was a PROTOTYPE, no? OKay, then, in THAT case... (but if anyone wants me to do a training video on how to properly debraid a coax.. I can comply!)

@NiHaoMike64 2 жыл бұрын

That little stub isn't going to make much difference at 2MHz.

@WarpRadio 2 жыл бұрын

@@NiHaoMike64 perhaps not, BUT.. we are talking accurate MEASUREMENTS, here, no? thanks for your reply :)

@EnricoConca 2 жыл бұрын

This current probe is designed to be used with a 1 MOhm input impedance scope, so the coax is just being used as a simple wire, not a transmission line. Furthermore, at 2 Mhz in coax the wavelength is just about 100 meters, and an impedance mismatch which is 1/20000th of a wavelength long is absolutely negligible anyway.

@WarpRadio 2 жыл бұрын

@@EnricoConca hello there and thanks for your reply; I see what you are saying, however, since he was reading the waveform directly on the 'scope (he said it was a "pass-through", I thought), I concluded that it was, indeed, passing low-frequency RF, and, even at 2 MHz, any impedance-mismatch (esp at a high impedance) would render an error in measurements; it seems that they went through the trouble to use COAX and not simple shielded cabling... and it appears to be tightly-shielded no less (as any good 'scope cabling should). :)