EO&N Capacitor Leakage Tester re-make with PCB. Design, Build and Testing

[@poormanselectronicsbench2021]

17:40 To "dampen" the meter action, you could add up to a 50uF, low voltage electrolytic cap. a lot of old test gear, including a Sprague TO-6A has such a cap ( C15 - 50uF - 3VDC) to help dampen spikes to minimize damage to the movement if something gets connected too harshly. It's very nice of you to share creations and not hide the info behind a pay wall, it helps keep interest in your channel and supports the community well.

[@electronicsoldandnew]

That’s a great idea, will try it directly across the meter connections.

[@TheTemporalAnomaly]

That`s a good point. That method was used in many commercially produced test instruments. Also two back to back diodes were used as well to protect the meters from massive over current needle bending events. But in this low current circuit the capacitor would suffice.

[@electronicsoldandnew]

👍

[@poormanselectronicsbench2021]

@@TheTemporalAnomaly Yes, I saw he wisely added the 1N4148's already as well ( check his schematic @ 16:35) The capacitor wont guarantee against damage, but it will take that sharp "pegging" out of an overloaded condition. The only drawback to it is if you like the movement to react faster to a change, but you can experiment with values as well.

[@electronicsoldandnew]

👍

[@mackfisher4487]

An elegant design, your DIN rail approach certainly makes for a nice clean bench. Thanks for sharing happy Christmas

[@electronicsoldandnew]

My pleasure

[@darrylgodfrey9604]

I made the v1.0 tester and can confirm that it works like a charm. Have used it many times since - more to confirm my suspicions about potentially bad caps than anything else. Thanks again for making these projects available.

[@electronicsoldandnew]

My pleasure

[@MarcelHuguenin]

Hi Manuel, thank you for your videos, I will keep following you. Have a great 2023!

[@electronicsoldandnew]

Thanks. You too

[@Sanyesz855]

Hello! Thanks for the video, I have such a DC-DC converter at home, it can handle 800 volts, but you don't need it!

[@radio-ged4626]

Not watched this yet, but just finished Christmas dinner and scanned KZbin and seen you've put this out. Will watch later as I am a little worse for wear. May well build this as I built your point to point capacitor tester and find it works really well. Happy Christmas to you and yours. Hope you're having a good time.

[@electronicsoldandnew]

A great time and also worse for wear, if I’m honest 😊

[@fredcommandeur8809]

Great project and always good to follow on your video's , Happy holiday's and a good, great and safe year 2023 for you and yours around you...

[@electronicsoldandnew]

Thanks Fred. Same to you and yours.

[@richardberg8279]

I suggest you add a led/resistor in parallel with the discharge resistor so you know when the cap is discharged.

[@electronicsoldandnew]

Good idea.

[@hernancoronel]

Hi Manuel, I love the original project series! I always watch those videos every now and then to refresh the ideas and drool over your creation but I could never justify getting the toroidal transformer like the one you used (I know I could used others but anyway). Thank you and keep up the great videos!

[@electronicsoldandnew]

👍 maybe this version will be more accessible. The toroidal transformer can be costly.

[@rogeriosimoes8778]

Hi Manuel, thanks for sharing such a professional tester, very usefull in any electronics bench. It will be my next 2024 project. As sugested in the comments I'll try to " "dampen" the meter action, you could add up to a 50uF ". Kind regards from Portugal

[@electronicsoldandnew]

👍 Boa sorte

[@jw200]

Thanks for the video. I will build it after I get some time. I have hundreds of used and new caps.

[@electronicsoldandnew]

👍

[@borayurt66]

It is a nice surprise for me that you got back to this project. If you remember I was very interested with it back then, I made a few tiny mods to your design to be able to use it for lower voltage caps and shared everything with you to get a technical approval. It has been working on a perf board since then and I've always wanted to design a proper PCB for it but never got around to it. Now that you have done the hard work, I will again be very interested to move everything to your new designed PCB. Following with great joy here!

[@electronicsoldandnew]

Good to know you’re using yours. I’m also quite anxious to get mine in the enclosure above the workbench so that it is even more accessible.

[@BjornV78]

Keep in mind that those little SMPS boards probably have a safety capacitor between the primary and secundary side of that pulse transformer, and this will add leakage from the mains to your negative side of your entire project. This leakage can go up to 50% or more of your mains voltage, and in the µA range. The digital voltmeter that you spoke off, needs also a separate powersupply , but the leakage from the SMPS gets his way into that digital voltmeter through the shared negative lead and that can have a influence on the voltage measurement. Happy holidays and have a nice christmas. Grtz

[@electronicsoldandnew]

I’ll keep that in mind when the voltmeter arrives

[@poormanselectronicsbench2021]

Not sure if that is an issue, because he is powering it with a 12VDC "wall wart" , so, it is not connected directly to AC mains voltage. There's a possibility the wall wart is also a SMPS design, but, he will have to check that himself. The other option that Manuel was considering, and configured for, was a 1:1 isolation transformer ( for his 230VAC mains), which would keep that from happening, but like he said, would add a larger cost to the build.

[@jernejq1651]

This SMPS is a DC/DC converter, so it probably has no connection to mains (or it depends on the source of DC you provide at its input). I'm pretty ignorant on the topic, but what kind of safety such capacitor would provide? And this being a non insulated topology (one end of both windings tied together) I cannot imagine where this cap would be not to interfere with the function of the transformer (essentialy shorting the windings - or is it so low value that it blocks the main switching frequency of the circuit, but lets thorugh any harmonics of it?)

[@EJP286CRSKW]

I suggest that the voltmeter should be across the DUT, not where you have it. That way you have a liveness indication for the terminals, for safety, and you can also see the discharge, and know when it is finished, and, again, when the capacitor and terminals are safe.

[@electronicsoldandnew]

Can’t do that or the current drawn by the voltmeter will read as leakage.

[@t1d100]

Excellent project! Ideas = 1) On the switch mode board, change out the cheap caps for high quality brands. I am betting that the voltage of the original caps is overrated. 2) Maybe consider adding an auxiliary input for a frequency generator to drive the DUT at different frequencies. Frequency is an important cap perimeter. Tips = 1) Always cover the e-caps (with a clear plastic sheet, cloth, etc,) when powering up a new module, for the first time... such as the switch mode supply. This limits any damage caused by an exploding cap. 2) Pots often come with two nuts and two washers on their stems. This is so you can set the depth of the offset of the pot. One nut and washer stays on the stem, the stem goes through the front panel and the second washer and nut clamps the pot in place. The face of the pot does not touch the back of the panel. This allows 1) the board to be offset from the panel, 2) the amount of stem protruding from the face of the panel to be adjusted and 3) the various pots to be evened up. I hope that helps.

[@electronicsoldandnew]

All great tips. Thanks.

[@cbiz8]

Manuel, como siempre un prolijo y didáctico video. Te deseo un buen 2023 and keep on this way. Saludos desde la cálida Buenos Aires.

[@electronicsoldandnew]

Thank you Carlos 😊

[@JohnGreen-SWL]

Thanks for all the videos during the year I have learnt a lot from them Have a great Christmas with your family and good health in the New Year

[@electronicsoldandnew]

My pleasure

[@OIE82]

Very elegant design and another great video. Merry Christmas.

[@electronicsoldandnew]

Thanks 😊

[@peteronel4051]

Ok I follow the testing ok but does testing tubular tuning etc capacitors test the same way ??❤ thanks compliments of the season regards Peter Onel

[@electronicsoldandnew]

You can test the leakage on any capacitor. Just be careful of the test voltage you apply.

[@peteronel4051]

Thanks I let you know the out come

[@johnkris753]

Nice as always 👍 Merry Christmas

[@electronicsoldandnew]

Thanks 🙏

[@bryandowdey1779]

A very interesting and practical capacitor leakage tester. Thanks for sharing. I do agree to be cautious with cheap switch mode power supplies or boost converters. I have seen many cheap switched mode power supplies where the layout and separation of high voltage parts were far too close to avoid tracking or arcing. Also the small transformers had very poor insulation and isolation between primary and secondary coils. Your circuit looks very straight forward and well thought through. Great designs are often relatively simple and simplicity often leads to good reliability. I look forward to your next video. Kind regards and a happy New Year!

[@electronicsoldandnew]

Thank you Bryan.

[@ukrainehamradio]

This is of course interesting, but in practice I just change all suspicious capacitors to new ones. Once I was very unpleasant in front of a person who contacted me again after the repair. The reason turned out to be in capacitors that had normal parameters during measurements, but after a while during operation they deteriorated again. Now I have a rule - no exceptions, use only new quality parts. I even stopped checking the parameters of the old ones out of curiosity.

[@electronicsoldandnew]

👍

[@barrymayson2492]

I must admit I'd do the same on some one else's kit if possible but sometimes the very large capacitance ones are not cheap so will often check them to see if it really is necessary. I also check most of the new ones I use had some bad experience with some what must be counterfeit or second's. No amount of time I have wasted chasing around thinking I had done something only to find dodgy components. So am going to build this tester for the bench probably get my friend to do so also.

[@electronicsoldandnew]

I’ve had similar experiences with new caps that are counterfeit.

[@silverXnoise]

@@electronicsoldandnewYeah, I mainly use leakage meters to check new caps and NOS items in my inventory before installing them. If someone else is paying, I’ll get fresh caps from Mouser and generally rely on their quality assurance, but more often than not I’m tinkering or putting together my own projects, and then I’m not above harvesting more expensive parts like bulk caps and reusing them. I think there’s plenty of good reasons for having a leakage tester in the workshop.

[@electronicsoldandnew]

👍

[@ernestb.2377]

Hi. Interesting DIY project idea. I was wandering how 'clean' does the DC test voltage needs to be in this case. As we talk about uA's could a 'poor' switching power supply introduce some unwanted error? If the switching frequency is not filtered enough it could cause some current through a capacitor. One remark on the rotary switch and safety. Does the rotary switch has the same function as in the old tester? Or you have an separate on-off switch? If you would have an separate on-off switch and you do a test, the DUT would stay charged until you turn the rotary switch to discharge position. The chance is big that one would just turn off the device after doing the test.

[@electronicsoldandnew]

The supply doesn’t need to be extra clean. It works well as us. The switch is in fact the same as the previous version. When using it, you must remember the sequence.

[@heinz8770]

Hi Manuel ! Thank You for the interesting video again ! 👍 In my leakage-tester I use a springloaded button for test, so only if I push this button voltage is on the DUT. If I release the button, the capacitor is discharged over a resistor like in Your set. This is for more safety, because You never have voltage on the DUT only if You push the button. So it is not possible to "forget" to switch of the voltage. It is only my mind and maybe You can use it also ! Greetings and late christmaswishes from Heinz from Austria😊

[@electronicsoldandnew]

I decided on this method as I like to increase the voltage slowly, rather than setting a voltage and applying it. Then, when I turn the switch back to the off position, it automatically discharges the cap. However, the push-to-make option is easily adaptable for anyone who wants to do so.

[@aliens1192]

Fantastic job! I enjoyed every second of this "course"! Be my guest for your next coffee! Greetings and best wishes from Germany! 🥹

[@electronicsoldandnew]

Thank you. I appreciate the support.

[@erikdenhouter]

Manuel, you are measuring with the Brymen on the auto scale. Check the manual, and you will see that picking a range by hand (off auto) you will get a 5x better accuracy.

[@electronicsoldandnew]

👍

[@oliverharris7366]

Merry Christmas from the States.

[@electronicsoldandnew]

😊 thank you. Same to you and yours

[@peteronel4051]

20.57 South African It looks absolutely amazing how about your schematic

[@electronicsoldandnew]

Link is in the video description

[@Sanyesz855]

Hello! A quick question, I also built it from the same DC-DC converter, but I noticed that the pointer shakes a lot at 2 mA and 200 uA, did this converter cause any electronic disturbances to you? thanks

[@electronicsoldandnew]

No, it worked flawlessly, but as I said at the start of the project: I don’t really trust these modules. I usually buy two or three to ensure that at least one of them works 😊

[@Sanyesz855]

@@electronicsoldandnew Hi, I have several modules, I will try another one, the one with the strange small capacity capacitor is a good example of 100 nf, could it be some kind of oscillation? I'll see what kind of module I have, I need 450 volts, I have a lot of capacitors...

[@electronicsoldandnew]

I haven’t tested the module beyond the application in this case, so I can’t be sure if the cause of the issue.

[@SereghiAlexandru]

Nice project! PCB power input can't be connected directly to the mains?

[@KeritechElectronics]

Hmmm, it may be an idea to make a switch-mode power supply with variable output voltage, with a benefit of a low voltage power input and a cheap high frequency step-up transformer. Noise is not really a consideration for capacitor leakage testing, so SMPS will do. I like the project as it is now though :).

[@electronicsoldandnew]

👍

[@pault6533]

Just wondering if a transistor circuit could replace the complicated voltage range selector and achieve the same results without the switch.

[@electronicsoldandnew]

Quite possibly

[@egilhansen8857]

The internal resistance of your uA meter is obviously 20R. If you put a 40R (39R) resistor in series with the meter and place the protection diodes across the combination of resistor and meter, then the voltage across the meter will be only 0,2V at the maximum current of 100 uA when the diodes start to conduct at 0,6 V

[@electronicsoldandnew]

By my calculations the resistance is 2160 ohms. The shunt resistors are all in parallel with the meter.

[@eltonmoore-fl1ev]

Thanks!

[@electronicsoldandnew]

Thank you

[@tommybewick]

Merry Christmas to you and your family!

[@electronicsoldandnew]

Thank you. Same to you and yours

[@DJDavo013]

A nice addon would be a spdt switch for the voltmeter. What annoys me when discharging a cap you don’t know it’s really discharged, especially larger caps… This way you have the best of both worlds..

[@electronicsoldandnew]

That’s a great idea

[@DJDavo013]

You’re welcome! This keeps it simple and easy to mod… i was thinking adding it to the selection switch but to much things to consider etc.. Let’s keep things simple 😊 Most of the times I use it for foil caps, but the last weeks i’m busy with reforming caps.. And i have to attach an extra multimeter to be sure i don’t zap testers.. Speaking about reforming caps.. An current selector would be a great addon too haha Maybe something for an upgrade?? But that would make the scaling for the ammeter a bit more complicated i guess Anyway love your work 👍🏻

[@electronicsoldandnew]

@DJDavo013 👍

[@pmacedo6778]

Viva!, onde aconselha comprar o módulo dc-dc. É sem dúvida mais barato que um transformador. Obrigado! BOM ANO🎉

[@electronicsoldandnew]

Aqui vai: www.ebay.com/itm/152986652658?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=XTMPZF_FQCG&sssrc=2047675&ssuid=m79L0L3YREu&widget_ver=artemis&media=COPY

[@pmacedo6778]

@@electronicsoldandnew , Muito Obrigado!!! Sugiro que indique onde adquirir alguns componentes como este DC/DC Booster e o voltimetro. O Video está fantástico como é hábito!!! Obrigado por partilhar !!! Votos de Bom Ano !!

[@davesage9190]

In one of the first design videos you had a 10 ohm resistor in series with the source of the mosfet. You stated it was for a bit of negative feedback so the mosfet circuit could regulate / stabilize the output voltage better. I see it's missing from the final design. Did you explain why? Very nice design thanks. I received my boards today. I'll be moving ahead with a build. Thanks for sharing. Thanks P.S. FWIW the silk screen for R11 is upside down on the board 🙂

[@electronicsoldandnew]

This circuit has that resistor in the transistor current limiter. It’s labelled R22.

[@davesage9190]

@@electronicsoldandnew Ok. R6 serves a dual purpose then. Fair enough. Thanks

[@jamesmdeluca]

Greetings: Suggestion: I have not yet worked out the method! But would like to propose an automatic circuit change, that is using a momentary switch to prevent leaving high voltage on the DUT leads. When the switch is depressed, the voltage is increased automatically and stops based on a leakage current you set on a pot!, and the appropriate led lights to match the current range where the leakage occurs. Releasing the switch discharges the cap while leaving the last test results displayed including the voltage at which the leakage was met. Maybe a slow 555 circuit could do it. Leaky caps will reach the leaky setting, while a good cap will have voltage rise to a limit set to avoid damaging the good cap. (A good alternate use for the rotary switch.) Just a thought, almost like an ESR meter. Paul of "Mr. Carlson's Lab" YT channel has a low voltage leakage tester with construction details on his Patreon channel.

[@electronicsoldandnew]

👍

[@EsotericArctos]

I remember when you were first introducing your capacitor testor in videos. It was pretty awesome. I made the Mr Carlson's version, but I also look forward to having a go at making your version once it is released :). I think there are times when you do need high voltage testing and not just a low voltage test. I hope you had a great Christmas with your family.

[@electronicsoldandnew]

I also considered building Mr. C’s version, but quite frankly, I got into the habit of using mine and it did all I needed, so I stuck with it. The only reason I’m rebuilding mine is to fit it onto my bench ‘test gear strip’, which makes everything easily reachable.

[@Stu66orn]

Hi, could you show schematic? I am thinking about building my own but not sure how complicated it is. Would like to see before paying for schematics

[@electronicsoldandnew]

It’s linked in the description of the video

[@Stu66orn]

@@electronicsoldandnew Hi, I mean Carlsons version

[@robertherendeen7702]

I ordered some boards today for myself and a friend, can you post the part number for the rotary switch? Thanks!

[@electronicsoldandnew]

I don’t have it. This is one of a lot that I had on hand. However, it’s a RS25 model from Alpha, and is shorting, 2P5T.

[@Stu66orn]

Could there be any problem with using another mosfet capable of 700v? What about 2w pot and 1n4148 If voltage is higher from transformer I have on hand?

[@electronicsoldandnew]

The mosfet will be fine as long as you heatsink it. The 2W pot is good, as it will handle the voltage better than the smaller pots. The 1N4148 I find a little fragile. Use a 1N4007 instead. It’s more robust.

[@Stu66orn]

@@electronicsoldandnew Thank you! Will the current limiter work same way with other mosfet like FCP20N60 or IXTP12N70X2

[@electronicsoldandnew]

Probably, but it’s best to check the cutoff voltage and adjust the resistor as needed. The higher the resistor value, the lower the current limit.

[@braveheart9275]

Great work. Thanks.

[@tiagomadeira838]

Bom Natal. E um próspero e feliz ano novo de 2023 para si e para os seus.. São os meus votos mais sinceros. Tiago

[@electronicsoldandnew]

Obrigado Tiago . Para si e família também.

[@torau5817]

Merry Christmas to you.! Why you dont take a double pole three position switch? BR Torsten

[@electronicsoldandnew]

Don’t need it. I only need two ranges but you can use a switch as you suggest to get three ranges of voltage.

[@JamesConway-s9q]

Excellent video, I watched a lot of videos on this issue and your is very interesting and informative to thanks for making the video and I fully appreciate you effort from Jim always and forever keep up the good work and I hope subscribing is helpful to your channel. ❤

[@electronicsoldandnew]

Thank you 😊

[@LouinVB]

D6 1N007 appears to be acting as a blocking diode vs a shunt to ground for the DUT. For a diode shunt would not it's anode be connected to ground?

[@electronicsoldandnew]

This diode just blocks DC current flow back into the device when the supply is switched off and in the event that there is still charge in the DUT

[@arenaengineering8070]

Thanks for the video! Best regards!

[@electronicsoldandnew]

Pleasure 😊

[@paulcohen1555]

I already voted 👍. I know it will be awesome.

[@electronicsoldandnew]

Thanks

[@Stu66orn]

Hi, do you know a way to calibrate without pot?

[@electronicsoldandnew]

Not sure what you mean

[@Stu66orn]

@@electronicsoldandnew Hi, you did calibration with 1k pot adjusting trimmers on the board. Is it possible to do that with a resistor of known value to calibrate using a multimeter

[@electronicsoldandnew]

Sure. If you bring in all the calculations for the meter’s resistance, etc. too much hassle.

[@ErwinSerle]

The link goes to all interesting Tube Tester files, not to a Capacitor leakage tester set of files, or am I missing something ?

[@electronicsoldandnew]

I just tried it again and it goes to the correct files. Here is the link again: drive.google.com/drive/folders/1sxGnUVc_3p2kmEsl8otx2GP2z4UvN3tD?usp=share_link

[@ErwinSerle]

@@electronicsoldandnew yes it does now ! Thanks.

[@ErwinSerle]

@@electronicsoldandnew although I still do not see this specific link in the grey area above this list of posts and under the video ..

[@electronicsoldandnew]

👍

[@paulcohen1555]

If you don't need high accuracy, maybe using a logarithmic current scale will be better? You will be able to easily see across four or five current decades on one scale.

[@electronicsoldandnew]

That would be an idea, but I’d have to get a new meter.

[@radiotvrepair1059]

Thanks 👍 and merry Christmas 🎄 can I use a Chinese high voltage converter voltage input 8--32v output 45--390 v only without using the card that you have made and using only the 2nd part of your diagram.

[@electronicsoldandnew]

That would work, but I’m actually a little afraid if these devices 😊

[@radiotvrepair1059]

@@electronicsoldandnew thank you for sharing the schematic diagram.

[@electronicsoldandnew]

My pleasure

[@tubeDude48]

👍👍👍

[@electronicsoldandnew]

Thanks 😊

[@anandarochisha]

Feliz Natal compadre

[@electronicsoldandnew]

Obrigado. Igualmente 😊

[@jernejkurincic9050]

Nice project! Which wattage is the pot you use - or recommend? Did you use any special type of rotary switch for such high voltages? I don't have a microampere meter - do you think chinese ones for cca. 5€ are any good or is it best to avoid them? What about using the one on the multimeter? Would Peaktech work for this? Also, on the schematic the switch in first position (discharge) probably shouldn't be connected in the amp range part (upper portion of the switch schematic) - or am I wrong?

[@electronicsoldandnew]

The pot is a 1 or 2 watt. Switch is answered in other comments.

[@980ssbbearcat2]

I like the KISS (keep it simple stupid)method better.

[@MidnightVisions]

I would replace those dodgy green Chinese capacitors, and replace them with reliable ones. They won't last a year.

[@electronicsoldandnew]

👍

[@douggale5962]

Do you really need to put your thumb 1mm from that sollder blob at the top? Is the switch really that hard to switch? Come on.

[@electronicsoldandnew]

?