Low Cost Cap Tester, ESR, LCR 2018

[bugi]

I've not seen ESD protection (if any) mentioned in finished products often, either, so I think that is sort of taken for granted (even if it shouldn't), and thus not detailed - or it doesn't have any ESD protection at all. Even DMMs touting "1000V" everywhere don't bother to mention if they have also been designed to take a 15kV ESD spike.

Those diodes are definitely meant to take the punch

It is not that it could not be done in general, but the components (or their pad layouts) I've seen have been SOT-23, and back-to-back series connected, which indicates something else than a V-forward drop (of parallel connection) to waste, and with no series current limiting, so plenty current, too.


In any case, after about half an hour of searching, I could not find a SOT-23 zener/TVS component which would have had low capacitance, low reverse leakage and be of suitable internal connection to fit into DE-5000 layout as is. Maybe I'll return to this topic if I some day just happen to bump into suitable component. For now, just have to remember to think before poking around.

[elgato]

The DE-5000 was delivered yesterday. Wish the clip leads were a bit longer but really like the tweezers.

Tried in-circuit : A 470 came back with 467, .04, 100 86 .4

Two 4700's either show nothing or nothing even close.

I do not think I can trust any of the in-circuit results. Shame because some are really tight.
Is this meter as good as it gets for in-circuit in this price range?
Thanks Again

[Shock]

I do not think I can trust any of the in-circuit results. Shame because some are really tight.
Is this meter as good as it gets for in-circuit in this price range?

Yes the DE 5000 is a keeper, the lack of input protection is the only concern so always make sure the circuits not live and discharge the cap (in or out of circuit). Remember you have to do this on other ESR meters as well most of the time anyway because they have limitations.

I would still consider a Silicon Chip (Bob Parker design) ESR meter and put the protection diodes in if you are doing a lot of in circuit measurements in TVs, Radios, Amps etc.

I'd buy both personally without hesitation. But one or the other can get you by.

[elgato]

Why do I get OL when measuring the 4700uF's. ?
What is the proper setup for larger values?
Thanks

[PedroDaGr8]

Why do I get OL when measuring the 4700uF's. ?
What is the proper setup for larger values?
Thanks

Check your frequency, >2000uF needs 100/120Hz range

Sent from my LG-LS998 using Tapatalk

[elgato]

Sorry to be such a noob.

At the 100 Hz range I get 4.32 mF so it is reading Capacitance.
However, both of the 4700's show zero ESR.

Limitation of the meter or am I doing something wrong?

[BravoV]

Sorry to be such a noob.

At the 100 Hz range I get 4.32 mF so it is reading Capacitance.
However, both of the 4700's show zero ESR.

Limitation of the meter or am I doing something wrong?

Some caps are rated at different frequency, simple thing to remember, when it comes to electrolytic, to measure capacitance, use 100 or 120 Hz, that is the standard way measured by the manufacturers. Just try download few popular electrolytic cap datasheets to note the "fine print", as its easily missed out.

When it comes to ESR , for common switching caps, its specced at 100 KHz, so set your Rs measurement at this frequency.

Also don't forget to read the fine print at those datasheet for it's ESR, sometimes its also called "Impedance" at certain frequency at different manufacturers.

Remember to discharge your cap EVERY-TIMES before measuring, as its normal when you have new toy to play and forgot this crucial step. 

[bugi]

At the 100 Hz range I get 4.32 mF so it is reading Capacitance.
However, both of the 4700's show zero ESR.

Limitation of the meter or am I doing something wrong?

Likely a sort of limitation of the meter. For example, on my meter, measuring 1000µF cap (which can be measured in the 1kHz range, too), at 1kHz the result is 964µF + 0.04ohm, but on 100Hz the result is 991.9µF + 0.0ohm. Note the drop of one decimal from ESR and thus the low ESR simply gets rounded down to 0.  And that cap isn't even any special low-ESR type, more than 10 years old random one, but unused.

(EDIT: in Rs measurement mode, at 100kHz, the result for the same cap shows 0.039ohm.)

[BravoV]

At the 100 Hz range I get 4.32 mF so it is reading Capacitance.
However, both of the 4700's show zero ESR.

Limitation of the meter or am I doing something wrong?

Likely a sort of limitation of the meter. For example, on my meter, measuring 1000µF cap (which can be measured in the 1kHz range, too), at 1kHz the result is 964µF + 0.04ohm, but on 100Hz the result is 991.9µF + 0.0ohm. Note the drop of one decimal from ESR and thus the low ESR simply gets rounded down to 0.  And that cap isn't even any special low-ESR type, more than 10 years old random one, but unused.

And if the old cap is reformed long enough at rated voltage, those values will change.

[elgato]

So,
To measure the 4700uF cap you need to select 100Hz but ESR will then show zero.
Then you select Rs mode and select 1kHz for an ESR value?

See pics.

Auto range is fairly useless?

Do the other meters, like the Atlas ESR70 simply do this in one step?

Does the MESR-100 auto range for ESR even at the higher values?

Thanks

[BravoV]

So,
To measure the 4700uF cap you need to select 100Hz but ESR will then show zero.

Yes, because "most" switching caps ESR are "rated and measured" at 100KHz, not at 100Hz, its a common industry practice.

Then you select Rs mode and select 1kHz for an ESR value?

More likely at 100KHz, not at 1KHz as most capacitors are made and measured at this frequency by the manufacturers.

The point here is to see if the capacitor is "STILL" in spec or at least near as new from factory, don't you agree ? 

Just download few cap datasheets to get the feel and clue.

Auto range is fairly useless?

No, actually pretty handy for components that we don't have doubt, just to verify its value.

The Auto has limitation, read the manual.

Say you have a cap that shorted inside, the auto definitely can not tell if its a cap or an inductor, or an inductor that it's coil is disconnected in the middle and mis-indentified as a cap, is this making any sense to you ?

If that is the case, then setting to manual to clear things out.

Remember, having both AUTO and MANUAL means we are in full control on what we measure, instead of leaving that dumb thing to decide as they're NOT smart enough.

Do the other meters, like the Atlas ESR70 simply do this in one step?

Does the MESR-100 auto range for ESR even at the higher values?

Never used those, but for me at least, an ESR meter is not in the league compared to a fully LCR meter as you own.

Some crappy ESR meter even can not differentiate between a shorted cap vs a low ESR cap. 

[BravoV]

Also as you mentioned you're a beginner, the word LCR means the "R" part is Resistance.

This new gadget of yours, when it comes to measuring resistance, it beats the hell out of any handheld DMMs out there, even the expensive ones. 

The ordinary DMM with 2 wires probe simply can not do this kind of low Ohm measurement reliably. 

[Shock]

To measure the 4700uF cap you need to select 100Hz but ESR will then show zero.
Then you select Rs mode and select 1kHz for an ESR value?
Auto range is fairly useless?

All ESR meters characterize capacitors differently due to the way they test, you need to read the manual it should tell you how to set the DE 5000 to ESR.

It will say on the capacitors datasheet what the capacitance tolerance is, or just look at an equivalent datasheet for similar type, capacity, temp, voltage size, series etc.

So as an example
+/- 20% @ 20C @ 120Hz.

ESR on low voltage low ESR aluminum electrolytics are often measured at 100kHz. Larger caps 10V up which state ESR can be 10kHz. Generic caps may have instead on their datasheet their quality/loss/dissipation etc measured at  1kHz or 120Hz. Take note of the trend, low performing caps are tested at lower test frequency, the ESR is higher. Generally you want to stick to the datasheet.

So as an example a datasheet has a low ESR 6.3V  8x11.5mm electrolytic cap 4.7 uF to 1000 uF
20C @ 100kHz = 0.056 or less Ohms Impedance/ESR
20C @ 120Hz = 0.22 Loss Tangent (provided if you need it)

You can also use those rough ESR charts that show Capacitance vs Voltage to get an approximate ESR, this could be old data as modern low ESR caps could have a lower nominal ESR value.

ESR when it's an issue due to the electrolyte breakdown is normally obvious. It may be over several hundred percent greater than the datasheet. Capacitors with high hours or sitting unused can have high ESR, the reforming/self healing nature of electrolytics can lower ESR. Heat can temporary lower ESR.

[elgato]

Thank you for all the input. I think I am starting to understand Cap Testing.
With the DE-5000 I get these results:

Junzl 100uF 400V   (http://www.paullinebarger.net/DS/Junzl/Junzl%20%5bradial%20thru-hole%5d%20TR%20Series.pdf)
 In Cs Mode:

 100hz Cap 88.17 ESR .9
 120hz Cap 87.95 ESR .8
 1khz Cap 85.6 ESR .57
 10khz Cap 77.1 ESR .52
 100khz Nothing "OL"

 Rs
 100hz .90
 120hz .83
 1khz .57
 10khz .51
 100khz.49

Rule of thumb and most generic tables are 100hZ so .90 is on the high side. Bad?

The Atlas manual says that it tests at 100hZ and the Blue at 100khz (?)
So you need to match your chart to the meter?

In the data sheet I did not see specific test frequency or ESR specs.

Thanks

[bugi]

You can calculate the ESR from the datasheet's dissipation factor. See https://en.wikipedia.org/wiki/Dissipation_factor.

However, your DE-5000 should also be able to give the D directly (i.e. dissipation factor, DF), just like ESR, so in the auto-C mode select the D for the secondary value... or ESR, whichever you want to see... or Q, or the "phase angel" (quoting manual for giggles).

As an example, my random unused 100µF/63V cap gives 98.94µF, and D=0.033 or ESR=0.4ohm (at 120Hz).

Compared to your values, mine has about half the ESR, and dissipation factor (compared to the datasheet you linked) is about 8 times lower.  Quick thinking from that would indicate that as your cap shows higher ESR, you should also see higher D, about 0.07 or so. Thus well within the datasheet specs.

(EDITED quite a bit, for missing one 0 from own value while comparing to DF from the datasheet, thus leading to totally different end result )

[Shock]

Thank you for all the input. I think I am starting to understand Cap Testing.
Rule of thumb and most generic tables are 100hZ so .90 is on the high side. Bad?
The Atlas manual says that it tests at 100hZ and the Blue at 100khz (?)
So you need to match your chart to the meter?

Capacitance and ESR are two separate measurements (in case you missed that). Therefore if you wanted to evaluate capacitance at 120Hz and ESR at 100kHz then you would chose those frequencies.

I'm not sure of the Atlas but the Blue ESR is only measuring ESR and I believe the Bob Parker designs are 100kHz. Your instrument is far more advanced as you can evaluate it at different frequencies. If referring to a chart (for simplicity) yes it does matter the test frequency. But they are ball park figures anyway, and as I mentioned earlier typically ESR will be several hundred percent greater if there is a problem.

The ESR is highly dependent on the voltage and capacitance of your cap (so it's minimal info required) and as I mentioned earlier many other factors. So it's hard to be accurate without the datasheet or even guess without the capacitance/voltage specs. If you look at a typical chart for the Bob Parker style (see below) you can refer to that. Or more accurately the datasheet and what Bugi and I were suggesting earlier.

Btw, you can say thanks also by clicking the "thanks" button (top right of each post).

[JDW]

I've been considering the purchase of an ESR tester for a while, and everything seems to point back to this thread and the DE-5000.  :-) 

I have some questions...

First, I found an EBAY auction shipping direct from Japan for a complete kit with most of the accessories for US$104.  But will the documentation be in Japanese or English (or both)?

Second, I've seen some clip mods that combine Kelvin Clips like these with the TL-21 PCB socket.  Anyone here try that?

And lastly, I see from previous posts that the DE-5000 needs to be set to different frequencies based on the capacitance and the voltage rating of the caps being tested.  Is this described in detail in the manual?  If so, does anyone have a link to a PDF version of the manual so I can see what's involved before I purchase one? Are there upper limits to what maximum capacitance and voltage rating can be tested?  Some of the electrolytic caps I intend to test are:

• 680uF, 400V
• 4.7uF, 350V
• 6800uF, 10V
• 1uF, 50V
• 220uF, 16V

Thanks.

[Shock]

In my option these are better, search for "gwinstek kelvin"
https://www.ebay.com/itm/252204657919

Manual https://akizukidenshi.com/download/ds/deree/DE-5000_manu_en2p.pdf
Both the specifications and instructions on setting the frequency can be found in the manual.

[JDW]

Wow, US$20 each for your preferred clips!  Here is the same brand but cheaper, and you get 2 of what looks to be the same clips plus attached wires for only US$27:

https://www.ebay.com/itm/262181748478


Some of the information I was looking for is on page 35 of the DE-5000 documentation (thanks for the link):



No mention of capacitor voltage limit, so it would seem I can test my 680uF 400V cap using the 2000uF Range and 1kHz frequency.

[bugi]

No mention of capacitor voltage limit, so it would seem I can test my 680uF 400V cap using the 2000uF Range and 1kHz frequency.

It depends on how that cap is used. If it is after a simple rectifier and sees mains frequency currents, then 100Hz/120Hz. If it is part of an active PFC circuit, it could see closer to 100kHz ripple, though biggest currents are still at the mains frequency.

Also, with DE-5000, you don't really "use a range"; it is auto-ranging in almost all modes. The table still shows the frequency limits for particular ranges of components to be measured, or correspondingly, component value limits for a particular test frequency.

[Shock]

Wow, US$20 each for your preferred clips!  Here is the same brand but cheaper, and you get 2 of what looks to be the same clips plus attached wires for only US$27: https://www.ebay.com/itm/262181748478

1. I own a set and they are fairly nice clips for the price
2. That link was an example, I'm not guaranteeing the best price
3. I provided the search criteria so people could look for themselves
4. That ebay item I linked was for 2x quantity
5. I recommend making a better set of leads
6. The clips I linked are actually banana plug compatible. If you needed cheap non shielded cables just attach your own cables. The ones that have leads already attached may be soldered into the sockets and are of questionable quality (in the world of Kelvin cables), this would be less flexible overall as getting decent clips is the initial hurdle and these are way better than the other brand.

[wasyoungonce]

.........................ESR only with protection is Silicon Chip or Blue ESR style with added input protection diodes.   DIY ESR only with protection is .......................

Hey Shock...I've have just ordered a Silicon Chip Mk2 ESR kit....what is the "protection diode mod"...I'm in the early stages of researching this but knew this Kit is well regarded.  Is this mod on Bob Parkers page?  Sorry for the ignorance.

Previous on suspect ESR caps I've either shot gunned replaced them (which has worked well for years) and or used the Mega328 multifunction kit.  But its time I went "more technical" in this approach...hahaha

Any advice appreciated.
edit:
Ok found reference to it on Bobs page...maybe I should  look before opening my mouth!
http://bobparker.net.au/esr_meter/esrhints.htm

[JDW]

It depends on how that cap is used. If it is after a simple rectifier...

The capacitors I intend to test have already been desoldered and removed from the circuit.  I basically need to just plug my caps legs straight into the meter, which seems possible without even using the test leads it comes with.

[Shock]

Ok found reference to it on Bobs page...

A couple of things with that mod. Don't get complacent and just slap your ESR meter on any caps. I think it's better to properly check the voltage and attempt discharging first.

You can't check battery resistance/health when you have the diodes installed (an alternate use for the ESR meter). It might be possible to make them removable, again considering safety is a good idea. There is probably other ways to do battery resistance/health as well but I've not looked into it.

[wasyoungonce]

Thanks Shock yeAh saw the info regarding battery measurements and I agree re: discharging caps first.  I have a nice probe with inbuilt bleed resistor for that

Brendan