Micsig Current Probe CP2100A/B Tests and Comparing

[Martin72]

Hi,

https://www.eevblog.com/forum/testgear/350mhz-scope-2020/msg3056674/#msg3056674

I decided to order one, take it to work and hopefully can directly compare to other probes we use.
100Apk, 2.5Mhz Bandwith….sounds nice.

Price is 375€ (Batronix), well, what do we get from others:

Rigol RP1002C for 1886€

Testec TT-CC990 for 1178€

R&S RT-ZC02 for 898€

Siglent CP4070A for 842€

None of them offers the claimed 2.5 Mhz bandwith, some offer more than 100Apk, some less.
But all got one thing in common:
They were unlikely more expensive.
Therefore, the Micsig is very interesting.
The Micsig, like all other I´ve linked didn´t got a degaussing function, like I know from our tektronix probes but also from the lecroy ap011 probe.
At home I got the Owon CP05+ Probe, for appx 190€ incl. VAT.
Well....hm....Ah, forget it, this thing is crap.
Bandwith is claimed by 200khz, in real it would be something around 100khz, very noisy, you could use this thing from 1A up.
Before I got the Hantek CC-65 Probe....God...

For it´s price, I expect the Micsig will do a better job than my Owon or Hantek, that´s for sure.
But what about to compare it with "state of the art" probes?
What we got on work are Tektronix Probes and Lecroy Probe.
Chances are given, I can compare the Micsig with them, if Time allows it.
So I would do a comparison between CP2100B, CP05+, A6302, A6303, AP011.

My greatest "fear" would be the noise level.
Using tek probes or the ap011 from lecroy, you have a really low noiselevel - Could the CP2100B have it too ?

Let´s find it out...
Missing degaussing function doesn´t concern me much, more important is the noise.

But first of all, I´ll send a offer request to batronix, it would be 3% off I guess.
But hey, taking all what you can get..

Nevertheless, the probe should arrive within the forthcoming week.

Any test suggestions ? Post it here.
DC current is self explaining, so no worries.
AC current I could measure up to 400hz.
Switching power current upt to say 10...20khz, depending on the DUT I could get on work.

To be continued..

[Martin72]

But first of all, I´ll send a offer request to batronix, it would be 3% off I guess.
But hey, taking all what you can get..

No discount at all, but it doesn´t worry me.
When it´s good, then it´s got excellent bang for bucks value(see first post).
If it fails (noise..), I´ll return it and got my money back.
Should arrive in 2 days...

[2N3055]

But first of all, I´ll send a offer request to batronix, it would be 3% off I guess.
But hey, taking all what you can get..

No discount at all, but it doesn´t worry me.
When it´s good, then it´s got excellent bang for bucks value(see first post).
If it fails (noise..), I´ll return it and got my money back.
Should arrive in 2 days...

Looking forward to see how it fares. Thank you for the effort.
For low level testing, few loops of wire and serial 50 Ohm on a signal generator could give interesting signal to see how it behaves down in noise land....

[Martin72]

Good idea 

[Martin72]

At last, I´ve found some specs for the lecroy ap011 which I want to compare with the micsig - from an old, downloadable catalogue.
(Would upload here because of some interesting articles inside, but it´s too big)
From the spec side, the ap011 looks ( of course ? ) better what accuracy concerns.
But I won´t know the original price for this…
Got the Information from DHL, the probe should arrive on wednesday.
First I will do some tests here at home, like 2N3055 suggest one, together with the owon probe.
After this, I want to take the both to work and trying to find something interesting to measure and compare.

[Martin72]

Got the Information from DHL, the probe should arrive on wednesday.

No….Today. 

First impressions, good building quality, clamp got not a gap between when it´s closed ( like the owon did..), very solid cable, not bad.
Maybe tomorrow I start some measurings or at the forthcoming weekend.

[TurboTom]

Have you got an option to evaluate the inductance of the probe? @100A, even a few nanohenries can be a lot. If too high, this may limit the usefulness of the bandwidth at the high current range.

[Martin72]

Hi, I´m afraid not.
But have a look at the specs.

[nctnico]

At high currents you can compare a shunt resistor versus the probe. You just need a way to send a large current surge.

[Martin72]

Shunts we got a lot, we got also ZES LMG power analyzers with high precision current transformers or internal shunts.
For a surge current, I think I could use our selfbuild inductance meter.
It was designed to measure filter coils nearly to their normal operating current.
We calculating the inductance through the voltage-time area via pulses send from an µC to a IGBT.

[Martin72]

First time playing around with it, some simple DC measures..
To get a higher current measure, 4mm banana cable was turning five times through the probe, power supply deliever 3A max.
Really nice: On the siglent you could choose between voltage or ampere in the channel menu, then the probe ratio will also changed from 1:10 etc. to V/A, makes it easy to find the right range.

Noiselevel….
Picture shows the noiselevel at 50mA/Div, for me it´s acceptable and a nice surprise.
Channel 4 shows the noiselevel from the owon probe....
Current was measured by my calibrated brymen bm869s.
At 10A the micisg beeps a warning and the 10A button is flashing, reminding you to change to 100A, nice.
This was the first play around, more to come soon..

[maginnovision]

I was hoping to add some extra probes to the mix but my bnc adapters are VERY noisy. A short across them had more noise than the owon. I suspect the ground is making poor/no connection since they're all safety adapters so you I don't die.

Looks good so far. The owon looks like it'd work much better for a dmm.

[Martin72]

I think the same about the owon.
Nearly a year ago, I had a thread started about it, doing a schematic from it.
It got a very simple circuit design and the claimed 200khz bandwith couldn´t be right.
Nevertheless, the "Noisetest" was positive, so I will take the micsig to work instead of returning to batronix.
What I will do there is a comparison between lecroy ap011 and, maybe a little unfair, to the good old tek probe.
Next time ac currents will be measured, also I try to measure the bandwith/risetime.
If I get the chance, I´ll do some measures on "real" DUTs ( we are in the market of building power inverters up to 200KVA, 50/60/400hz, switching frequencies between 1.62....20khz)
Tomorrow I´ll try 2N3055´s suggestion.

Edit:

What else I want to try is using a power bank instead supplying the probe  from a USB port, to see if the (actually low) noise level could be further decreased with it.

[Martin72]

Did it..

Using the nice bnc-adaptors, I took the internal generator as source and the "load" was the internal 50ohm Input, then turning 10 wires through the clamp.
Below some measurings like risetime, several sinewave frequencies and....If I got bode plot on board, why not use it...So I´ve done it.
The testsetup especially with the 10 windings could not be perfect but at last, I´m surprised about the micsig in a very positive way.
Next step, comparing at work….
Martin

edit must measure the risetime again, wrong channel...

risetime added

[2N3055]

That is decent small signal response, and noise is quite low..  Nice work Martin! Looking forward to next episode!

[voltsandjolts]

Micsig has been a pleasant surprise for me too.
I've bought two of their tablet scopes, best portable scope for the money IMHO.
Will be interested in your test results.

[Martin72]

Next week is a short one due public holiday on thursday, so I have three days to "steal" a little bit time and some gear..
Goals are the mentioned comparison between tektronix 50Mhz clamp and the lecroy what accuracy, risetime/bandwith concerns.
Also I want to measure "real" high current and not turning windings through the clamp.
Well, we´ll see what happen.

[tautech]

Martin, in this screenshot there appears some significant current probe propagation delay:



Can you use the channel 1 deskew to see how much delay the MICSIG current probe inserts into the measurements ?
Does it meet the manufacturers propagation delay spec ?

[Martin72]

Hi,

Will do it in the next days.

Martin

[Martin72]

Comparing three probes noiselevel at 50mA/div. on the hdo6043a, Tektronix, Lecroy and Micsig.
"Of course" the Micsig is noisier, but not much - Excellent.
@tautech: Probe is at work, will looking for, if the lecroy got the deskew function too.

[tautech]

@tautech: Probe is at work, will looking for, if the lecroy got the deskew function too.

All half decent scopes have channel deskew. 

SDS5054X SDS5104X with 3 current probes....ch1 probe broken 
Ch2 menu showing deskew WRT the ch4 voltage probe.

[Martin72]

All half decent scopes have channel deskew.

Never used this, so I must look at it. 

[2N3055]

All half decent scopes have channel deskew.

Never used this, so I must look at it. 

It's in Channel setup, in preprocessing, on the right..

[Martin72]

Next week is a short one due public holiday on thursday, so I have three days to "steal" a little bit time and some gear..
Goals are the mentioned comparison between tektronix 50Mhz clamp and the lecroy what accuracy, risetime/bandwith concerns.
Also I want to measure "real" high current and not turning windings through the clamp.
Well, we´ll see what happen.

Unfortunately, I got no time at work this week - Except this one..
"Real" DC current measure up 100A.
The tek probe was in use, so I compare it with the lecroy ap011.
"reference" was a shunt, voltage measured by fluke 87V in hires mode, scope was a lecroy hdo6034a.
Source was a 100adc supply in constant current mode.
The cp2100b was every time in it´s tolerance values, also the ap011 - Remarkable: The claimed 15% from 40A up wasn´t reached at any time, worsest deviation was 4.22% at 100A.
Nice..
Hopefully, AC measure and switching current measure I could make next week on work.
I´ve took it back to home, making the measure tautech asked for it.

[Martin72]

Can you use the channel 1 deskew to see how much delay the MICSIG current probe inserts into the measurements ?
Does it meet the manufacturers propagation delay spec ?

Hi,

Specs were <150ns (10A), <200ns (100A).

Below 2 pics without deskew and with max deskew on ch1.