#776

[@davidv1289]

Interesting video, Scott. When testing electrolytics in addition to value and ESR, D or Q checks I like to hook them up to a Sencore Capacitor Analyzer which measures leakage current in tens of microamps at the rated working voltage. Also great for reforming large caps. I worked on systems that contained several Farads of capacitance and we always checked/reformed new capacitors before installing them.

[@krz8888888]

The the nichicons on the meter again after leaving them charged up for some time, I think they need some reforming when staying on a shelf for a long time

[@helmuthschultes9243]

You would love to see the old 470,000uF supply capacitors on the original ALTAIR and IMSAI home computers if not run for 30 to 40years. On new powerup if not carefully ensuring repolarising by very short 1 to 2 sec power cycles with many minutes gap on off state. Then over a few days progressing up to minutes in stagrs, you could blow a hole in your ceiling with computer l8d off or buckling the steel lid if on and gilling your room with pungent smoke and gunk /paper/foil chaff. I managed ok after 30 years, but afew people resurrcting old computers have had need for medical attention. Those computers had up to 6 such or similar capacitors between 100,000 uF and 470,000uF with 10v to 25v ratings. Large can types! All Electrolytics with over 10 years unpowered storage deserve carefull repolarising. Low voltage and current limiting essential or only bery brief power cycles for some time before progressing to longer power on or higher voltsges, if monitoring current no full power on

[@theawt]

very nice video. I wish I could learn how to judge when a capacitor is good or bad by looking at the esr, D, etc… I never found a reliable guide or tutorial

[@scottashcroft7001]

Not that surprising. The shelf-life of electrolytic caps is often much shorter than the service life. The main failure mode is evaporation of electrolyte due to the rubber bung not being a perfect seal. This is true even for the top brands.

[@westelaudio943]

That's what causes high ESR after decades, it's not the problem here. It is depletion of the oxide layer after sitting with no voltage for too long

[@AndrewJones-tj6et]

Great topic Defpom. Your measurements to determine the quality of an electrolytic is interesting in that there is a whole lot more than just capacitance, ESR or dissipation. I'm wondering what standardised tests one would do to confirm quality of electrolytic's.

[@IanScottJohnston]

Years ago I wasn't too bothered about what I buy from China via Ebay......but these days I must admit any wet products like elecytolytic caps I'll bite the bullet and pay 10x more via RS etc. Meanwhile, Suntan caps I'll now be on the lookout for in my own parts bin.......Cheers! PS. DF on electrolytics or any caps over 10uF by the book should be tested at 120Hz I believe.

[@andrevanstiphout]

I know that my query is a long time coming but have you had any experience with Suntan metal poly caps. They seem to perform well in speaker crossover systems and I've never had any problems with them as they all have measured well within tolerance. I should point out that the ones I purchase are 250v ones and I'm unlikely to ever go beyond 100v even in high powered systems.

[@michaelcranstoun8296]

Great video!

[@Drew-Dastardly]

Measuring new old stock capacitors right at the spot where the bandolier tape is full of glue that has leaked is not a good idea if you want to test them. Big Clive mentions this when he snips old through hole components right in the nice clean middle of the leads.

[@dirtydon8661]

In regards to the nichicon cap with higher ESR, I bet if you gave it some dc voltage then test ESR again it would have good ESR. I’ve experienced this before with older stock nichicon caps!

[@antibrevity]

Good video topic, but it would be great if you could also share some affordable ways to *get* a useful selection of quality electrolytic capacitors. I don't want to buy cheap electrolytics and have seen how worthless they are in actual circuits where their inadequacy and/or failure results in unreliable projects and often damages far more expensive components, but how can we practically obtain a selection of high-quality caps on a budget? *That* is the video I want to see :).

[@bigpimp347]

nice to see you rehearsed before you went in to full record mode..

[@PeterMilanovski]

As crappy as capacitors are when sourced from jaycar, I think that if you hooked them up to your power supply at a lower voltage and raised it periodically till you reached their rated voltage, then discharged them, they might have woken up and come back to life! But you have to go easy on the voltage and current.. the only problem apart from the time that it takes is that the majority of lab power supplies only get to 30V. Which is what I have, so for me to test a capacitor that is rated above 30V, I have to use a DC to DC boost converter which isn't ideal but it works... But I'm still looking for a better affordable option. How's your capacitor tester? I just saw those things on eBay today, I was considering one that was reviewed on X RayTonyB's channel which he posted recently! It doesn't look as nice as your one but it manages to display all the details on the one screen where I noticed that you have to push a button to see the dissipation which is a real pity because the screen is big enough to fit everything...

[@mysock351C]

Never seen a video of capacitors actually reforming in real time like that first one did.

[@xr6bat]

where did you get the Double-banana plug to USB Type A adapter for your power supply?

[@Adrian_Finn]

Well they failed safely at least! lol I just performed the same tests on a bunch of my Suntan caps and they were all fine, looks like maybe you have a bad batch there...Still they are no substitute for good quality Japanese Caps which I tend to use when it really matters.

[@SuntanTechnology]

Hi,Happy Chinese New Year,this is Suntan Say greeting to you. We are so sorry that our product bring your unpleasant experience. Can you tell me where did you buy these capacitors? Do you have Lot number? In generally speaking, aluminum electrolytic capacitor have a short shelf life, also easily affected by storage environment. Are you interested to retest our capacitors? we are willing to send to you for free. Thank you a lot.have a nice day again！ Best Regards, Suin.

[@caroleupene3237]

I just changed all the capacitors in my amplifier and tuner with mostly Suntan capacitors and I am Very happy with how they perform. I would definitely use them again.

[@SuntanTechnology]

@@caroleupene3237 yes,thank you. May I know your email address?

[@westelaudio943]

​@@SuntanTechnology I have unused Suntan 1000uF caps bought five years ago. No short circuit. Are they safe to use?

[@SuntanTechnology]

​@@westelaudio943 Thank you for the message. To better understand your on-hand items. Could you please tell me where you buy these capacitors? Do you have the LOT number? Or please email us for more details information, thank you.

[@westelaudio943]

@@SuntanTechnology Don't really remember. I bought them for a receiver back then iirc, now I wanted to use the rest. They seem to work alright though 👍

[@krz8888888]

That nichicon seemed to be reforming slowly on thr lcr meter

[@informediatech-bruno5766]

this video like CAPACITOR ASMR

[@willthecat3861]

According to Rubycon... "Leakage current of Aluminum Electrolytic Capacitors may be increased after storage for a long time. Conduct electrification [reforming] treatment for such capacitors before use.Electrification Treatment: Connect a 1kΩ resistor in series with the subject capacitor, and apply the DC voltage as high as the Rated Voltage for 1 hour.Discharge the capacitor through a resistor of about 1Ω/Volt after the electrification."

[@TheDefpom]

Interesting info, thanks for sharing

[@allthegearnoidea6752]

Alway a problem with the stuff from China. Undoubtedly some Chinese capacitors are just as good as the big name brands but due to very poor control in the supply chain it’s a gamble. I guess it depends on the stuff your manufacturing for me I could never afford to install a non brand but if your building a dollar farting dog toy then only the components price point matters. A lot of capacitor do improve with use as they will reform if not used in a while. Unfortunately it also goes the other way on occasions.

[@GregM]

Much magic smoke released.

[@helmuthschultes9243]

... sorry sent prior off incomplete... And ensuring current is not over several mA for lower values an 10's mA on very large capacitors.

[@antibrevity]

Good story about your experiences resurrecting large, old caps. For what it's worth, you can edit a comment after posting it with the little 3-dot icon to the right of the comment. Making a second comment will not work because the comments will not be sorted together for readers. Editing is best, but replying to your own post is better than a brand new comment.

[@rcfaudioitalia6110]

Will blow & destroy other part of the board. will smoke & leak liquid. it's hard to find original good capacitors. usually, aftermarket caps are cheap & mediocre quality.

[@markhodgson2348]

Dip it in epoxy and then do it