[First post] Fake x2 capacitors? - Page 1
Forum section: electronics / projects

author: RukyCon
author_rank: Contributor
timestamp: April 20, 2017, 06:39:54 pm
content: Hello, i'm new to the forumJust wanna know if some people sell fake x2 safety capacitors on eBay.

author: james_s
author_rank: Super Contributor
timestamp: April 20, 2017, 06:59:47 pm
content: I don't know, but given the number of fake/counterfeit components there are on ebay, I personally would not take that risk. If you need a safety component like that, buy them from a reputable vendor. Digikey, Mouser, Newark, etc, then you will know you are getting the real deal and can rest knowing that it probably is not going to burn your house down.

author: RukyCon
author_rank: Contributor
timestamp: April 20, 2017, 07:24:32 pm
content: That dose make sense because i did find this cap...

author: TJ232
author_rank: Frequent Contributor
timestamp: April 20, 2017, 07:24:43 pm
content: In this list of words aresomeof them that never should be put together in a sentence:"x2" "safety" "capacitors" "fake" "eBay" "Aliexpress" "Alibaba" "Farnell" "Digikey" "Mouser" "Avnet"

author: RukyCon
author_rank: Contributor
timestamp: April 20, 2017, 07:33:15 pm
content: Here's a cheap 0.47uf one i have.Do you see anything wrong?

author: wraper
author_rank: Unknown
timestamp: April 20, 2017, 08:02:30 pm
content: Quote from: RukyCon on April 20, 2017, 07:24:32 pmOn that photo is just a usual film capacitor, not safety rated

author: TJ232
author_rank: Frequent Contributor
timestamp: April 20, 2017, 08:02:50 pm
content: Look below what I have on my table right now. Do you want to know about how many we changed in the last month just in some termostat units?PS: it's yellow, very yellow, like yours, just have a crap camera and light.

author: Audioguru
author_rank: Super Contributor
timestamp: April 20, 2017, 08:40:40 pm
content: Isn'teverythingsold on ebay fakes or rejects? That is how they have very cheeeep prices and frequently the shipping from China is free.I support my local REAL parts distributors who sell genuine items at reasonable prices.

author: james_s
author_rank: Super Contributor
timestamp: April 20, 2017, 08:47:08 pm
content: A lot of the stuff is, not everything though. Even the real stuff is pretty much all made in China now, since all the manufacturing is in China, all the surplus is in China. It's the same way it was here back in the day with surplus stores carrying all sorts of leftover stuff from manufacturing runs, only it's also mixed in with fake/counterfeit junk. Some of it is just fine though, like Maxim LED matrix drivers, they cost a small fraction of what buying them from a US distributor charges. I dunno whether they're fakes, 3rd shift, copies, surplus or what but someone did some analysis of every variation they could get their hands on and they all worked perfectly. The $2.50 Arduino clones work perfectly, so do the 99c buck regulator boards. I'm not going to use stuff like that in a production item but for hacking together hobby projects they work fine.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: April 20, 2017, 09:20:10 pm
content: Quote from: RukyCon on April 20, 2017, 07:33:15 pmFake. UR mark is not correct.http://www.ul.com/marks/ul-listing-and-classification-marks/appearance-and-significance/marks-for-north-america/

author: wraper
author_rank: Unknown
timestamp: April 20, 2017, 09:22:55 pm
content: Quote from: Tomorokoshi on April 20, 2017, 09:20:10 pmI don't see anything wrong with it.EDIT: I found one panasonic cap desoldered from somewhere, and that have the ugliest UL mark I ever seen.

author: james_s
author_rank: Super Contributor
timestamp: April 20, 2017, 10:27:43 pm
content: The question is did that part come from that company or is it a knockoff? There are lots of knockoffs of other questionable quality Chinese brands. Not long ago I came into possession of a knockoff "Uitra Flrc" 18650 cell that looks very much like UltraFire, itself a rather dubious brand.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: April 20, 2017, 10:50:48 pm
content: Buying from a reputable distributor may give you a better chance of getting a part that is not counterfeit, but it isn't a guarantee. There are unethical people all over the world, and where there is a dollar to be made, occasionally something bad slips through. Unless someone you have good reason to personally trust has audited each and every step from manufacture to delivery to your door you don't really know what you are getting.Industries that really care about this sort of thing (aerospace, medical and the like) spend a lot of time and money trying to assure that their parts are good - and have failures in this process from time to time. Fortunately the ones most interested in this find the problems before the parts are delivered to customers. They do it by taking samples from each purchase and testing them to manufacturers specs, de-packaging and examining the contents and other measures. Then people often complain about the high price of their products.

author: james_s
author_rank: Super Contributor
timestamp: April 20, 2017, 10:57:24 pm
content: Few things in life are guaranteed, but buying from a reputable distributor certainly greatly increases your chance of getting a genuine part.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 01:44:56 am
content: Quote from: wraper on April 20, 2017, 08:02:30 pmBut, someone can relabel the capacitor and make it look like a x2 cap.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 01:57:37 am
content: Quote from: Tomorokoshi on April 20, 2017, 09:20:10 pmI was trying to point out that weird hole/bubble below the right leg.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 02:04:46 am
content: Here's a newer x2 capacitor i have.I have a feeling that the UR marking is fake.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 02:26:30 am
content: Does the color of the capacitor matter at all?I know that with electrolytic capacitors color does not matter.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 02:43:30 am
content: Quote from: blueskull on April 21, 2017, 02:37:37 amThanks, just wanted to know.Oh, and i've seen green x2 caps

author: james_s
author_rank: Super Contributor
timestamp: April 21, 2017, 02:47:55 am
content: Quote from: RukyCon on April 21, 2017, 01:57:37 amThat's an air bubble on the surface of the epoxy potting. Not exactly a sign of extremely high quality but not necessarily a problem either.

author: Gyro
author_rank: Super Contributor
timestamp: April 21, 2017, 01:26:57 pm
content: How many posts does it take to tell a newbie - Don't buysafety criticalparts on ebay, buy them from a reputable distributor. Simple as that!

author: Fungus
author_rank: Super Contributor
timestamp: April 21, 2017, 01:38:02 pm
content: Quote from: Audioguru on April 20, 2017, 08:40:40 pmNot everything, no.But ... it's almost impossible to tell from the adverts and/or prices of stuff. Mostly the sellers don't even know what they're selling. I've bought the same stuff twice from the same seller via the same advert. One batch was perfect, one batch was junk. Go figure.(I think some sellers advertise stuff then go downtown to get some if anybody buys. You'll get is whatever is in the market that day).The real trick with eBay is to underpower and overrate everything. If you need a 10W power supply, order a 20W supply and you'll probably be fine. Need a 10W LED? Buy a 20W LED and underpower it. etc.Or... buy from Russia/Israel. Those guys usually have quality stuff, but you'll pay for shipping.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 01:54:53 pm
content: There seems to be a few mixed opinion's about the x2 caps, i have some people telling me that i should not use ones from eBay, but then i have some people telling me that there most likely ok to use.And i'm not the type of person that buys all of there parts from eBay. example: i was repairing an old power supply [some of the output caps had failed] and i got all of the parts to do it off of mouser.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 04:32:24 pm
content: Quote from: RukyCon on April 21, 2017, 01:54:53 pmNo really, this is almost a tradition on the EEVblog forum now, so I guess many people don't even feel like commenting anymore.Anyone who really has used Ebay to source their components, and really used them, knows really well that the fake ratio is just horribly massive. It's a total joke. Granted, in some product segments, you mostly get good stuff, but in some others, such as alu elcaps, discrete semiconductors like power FETs, LEDs, etc., you get basically over 90% fakes (or otherwise unusable or severely out-of-spec stuff).On average, is it 5%, 20%, 50% or 70% crap, I don't know, but it doesn't matter; the ratio is too big anyway, so that anyone who has tried it too many times, has stopped buying the Ebay parts; except when theyknowwhat they are doing, or simply have to take the risk.Back to the EEVblog forum tradition; threads like this show up all the time, and it'salwayspeople telling you not to buy the Ebay parts - which is a great general advice for any beginner - and then we see blueskull defending the market. I understand very well that he's irritated due to the more or less hidden rasistic undertones people too often show.I like doing business with the Chinese, and I don't like the "everything Chinese is a scam or super shitty quality" mentality, which is plainly wrong.But this is something we should andcanevaluate based on facts, not feelings. The ratio of bad stuff sold by Chinese Ebay sellers is just huge. This is a fact that everybody can confirm on their own. I have bought a lot of stuff and know very well my defect percentage is somewhere around 30-50%. Today, it's a lot less, since I only buy Ebay stuff I think I can trust on, such as pin headers. But buying the Ebay components cannot be recommended for a beginner, nor when it comes to a safety-critical component. X2 capacitors wouldn't be on my Ebay list!

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 05:11:08 pm
content: What if i only plan on using them on custom projects? [Like small LED lights]

author: james_s
author_rank: Super Contributor
timestamp: April 21, 2017, 05:14:37 pm
content: Yeah I'd like to make it clear that when I complain about "Chinese sellers" I'm not complaining about the general population of China, nor am I implying that everyone in China selling stuff on ebay is a scammer, but there are a LOT of scammers selling junk on ebay so the problem is that you don't really know, and it seems the Chinese government is either unwilling or unable to do much about it. I suppose it's a natural consequence of having a red hot market, massive quantities of surplus components, and large numbers of people trying to scrape by and make ends meet one way or another, with a huge pool of buyers way off in a distant land so there is no direct interaction, one can't inspect the goods prior to purchase, and returning defective goods is not cost effective. It's an environment that is ripe for scams.Now as for buying parts on ebay, some of it is good, some of it is junk, if you know what you're getting or don't mind taking a risk then there are some deals to be found, but buyer beware. There are things I'll buy from unknown offshore sellers and there are things I won't. Safety components like X2 capacitors and high voltage fuses are one of those things I won't. It's just not worth the risk.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 05:23:04 pm
content: Probability theory excercise: Buy 20 components for a project. At 30% fault rate for each component, what is the probability that at least one in the project is faulty? If you spend, on average, 10 hours of debugging caused by each faulty component, how many hours (expected value) are you going to spend on this 20-component project?My experience on my own projects as well as debugging a lot of others' projects is that while it often works to buy an Arduino board, an LED and a resistor from Ebay to blink the LED, when the project gets any more complex than that, the chances that at least one vital component is broken in a funny way asymptotically reaches 100%. For example, it takes some debugging to find out why a 3V3 regulator is giving out 1V8. As a beginner, you always doubt your own work, which is correct because, when using genuine components, you are the source of 99.9% of the problems. But when you mix in a bagfull of faulty components you need to debug and swap, working for hours and hours on them just to find that they were faulty to begin with, then order some more, wait for a week to get the new parts - which again may be broken - you are creating an environment where you'll never get your project finished until you lose all your motivation.Another issue is that you typically cannot source all of the components needed in a project from Ebay, so you "need" to buy from a proper distributor anyway.Ebay is great for sourcing some trivial parts that for some weird reason are missing from the distributors, are hard to find, or are prohibitively expensive for what they are. For example, I have bought several $1 flux pens when FARNELL was, at the time, only selling flux pens for $100/ea(!).

author: wraper
author_rank: Unknown
timestamp: April 21, 2017, 05:47:45 pm
content: Quote from: Siwastaja on April 21, 2017, 05:23:04 pmI guess you are talking about Bonkote Bonpen. First of all, they are not $100 each but $100 for a pack of 5 which is standard packaging. But you can find places which will open the pack and sell them individually. Secondly those sold on ebay for cheap are all crappy counterfeits, are not ESD safe and don't perform anywhere nearly as well as genuine stuff (tried that crap for comparison).

author: Seekonk
author_rank: Super Contributor
timestamp: April 21, 2017, 05:49:14 pm
content: I don't really think of X2 caps as "safety" application. If something is line powered there is always a potential for things to short hence the need for some interruption. If you buy a polyester X2 cap, then whats the point. After common mode inductors they often go to standard capacitors. And there are no standard capacitors, they are all designed for particular applications. X2 caps are at least some implication that they are designed to operate without corona degradation. I've designed many 480V line powered devices with capacitive dropping and brought them through UL without X2 caps. The caps were designed to withstand AC. Unfortunately most data sheets for capacitors are including less and less information. Hard to figure out what the limits of some capacitors are. If you buy a lot of capacitors you get access to engineering dept and they will even design capacitors for you. I've always found these calls fascinating.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 05:55:58 pm
content: I do test the parts before soldering the onto the board.I even test the parts i get from mouser and digi-key.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 06:03:05 pm
content: Quote from: RukyCon on April 21, 2017, 05:55:58 pmThe issue is not within completely nonfunctional parts, they are easiest to identify.Parts that are "tested OK", but misbehave or have reliability issues can end up being horrible wastes of time, and hard to debug in actual full circuit. And these are surprisingly common.Proper testing takes a lot of time and equiptment, too, if you try to characterize the components.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 06:07:32 pm
content: Quote from: wraper on April 21, 2017, 05:47:45 pmFlux pens I have bought from Ebay for $1 are certainly not counterfeits since they don't claim any other brand than their own, thus, they are genuine. They don't even try to look like the Bonpens, or any other brand name thing. Indeed, I'm sure these are not ESD safe, but these do work fairly well.Sometimes, getting a workable but lower quality option for 1/100th the price of the good alternative is a good choice. This principle doesn't, however, work with most Ebay components, since they are usually priced at near distributor prices, and the parts can cause countless hours of debugging, something that cannot be described simply as "lower quality".

author: wraper
author_rank: Unknown
timestamp: April 21, 2017, 06:13:43 pm
content: Quote from: Siwastaja on April 21, 2017, 06:07:32 pmwell, basically if you search for flux pen on ebay, basically there are 2 things. Fake bonpens and other type which is like marker. Those are much worse than a brush. And similar (but much better quality) flux pens don't cost nearly as much as bonpen even at digikey.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 06:34:09 pm
content: Quote from: Siwastaja on April 21, 2017, 06:03:05 pmNow if i'm going to use them for something like a capacitor dropper supply, wouldn't be easier to diagnose the problem?

author: james_s
author_rank: Super Contributor
timestamp: April 21, 2017, 06:35:01 pm
content: X2 capacitors are classified as safety devices, they may be connected directly across the line. If they fail, they must fail gracefully and not catch fire or sit there and smolder. If you want to take the risk, I'm not going to stop you, but I don't think I personally would.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 06:35:50 pm
content: Quote from: wraper on April 21, 2017, 06:13:43 pm... if you can find them. In that case, Farnell couldn't deliveranyflux pen under $100, and Farnell was our preferred distributor.It's very well possible that Farnell had the actual flux pens I was looking for miscategorized or mislabeled. This frequently happens with them. I could have called their support phone. It's a hassle.Nowadays, due to too many utter fails, I tend to refuse to use Farnell and prefer Digikey instead mostly due to their usable website.Anyways, my point was that sometimes due to some reallysillyreason it is impossible to get trivial things from the distributors. Often it's a catalogue mistake, leading to spending a full working hour just to find the part number for a trivial low-cost plastic or metal part. These working hours do have a cost. Inability to get a flux pen under $100 at a certain time was a personal example, maybe not the best possible.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 06:37:57 pm
content: Quote from: RukyCon on April 21, 2017, 06:34:09 pmYeah, in a capacitor dropper it's more about the chances of it catching fire later on, than debugging some issue initially.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 06:44:10 pm
content: Can a fuse possibly reduce the chance of that happening?

author: Siwastaja
author_rank: Super Contributor
timestamp: April 21, 2017, 06:47:46 pm
content: Quote from: RukyCon on April 21, 2017, 06:44:10 pmOf course it can, but it's not a silver bullet.Any component not becoming a "full" short, but a resistance instead, can itself become a heater element causing excessive heat, leading to fire. But the fault current might not be enough to trip the fuse. This is a known failure mode with capacitors. The very idea of the X2 capacitor is that it's designed so that this is extremely unlikely.

author: james_s
author_rank: Super Contributor
timestamp: April 21, 2017, 06:53:04 pm
content: A fuse is certainly a good idea though, regardless what capacitor you use. Something rated high enough for the voltage, with a current as low as it can be without risking false trips.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 06:58:07 pm
content: Quote from: Siwastaja on April 21, 2017, 06:47:46 pmThat's why i said reduce, not prevent.Now, which would you trust more, eBay x2 caps or salvage x2 caps. [EDIT: Forgot the L in salvage so i put it in.]

author: james_s
author_rank: Super Contributor
timestamp: April 21, 2017, 07:11:24 pm
content: Savage? Did you mean salvage?Personally I would trust salvage more, assuming they are in good condition and came from reputable equipment.

author: RukyCon
author_rank: Contributor
timestamp: April 21, 2017, 07:15:10 pm
content: Quote from: james_s on April 21, 2017, 07:11:24 pmYes, i did mean salvage, My bad.

author: Fungus
author_rank: Super Contributor
timestamp: April 22, 2017, 12:43:04 pm
content: Quote from: Siwastaja on April 21, 2017, 04:32:24 pmYes, but the price of buying "good" stuff is sometimes so high that it's often worth buying two or three lots from different sellers and crossing your fingers.eg. Here in Spainanyorder from Farnell et. al. carries a minimum 15 bucks shipping cost.Stuff like MOSFETs and voltage regulators are almost all rejects/fakes (apparently) but even so it's only a real problem if you're selling them to people or planning to use them at high power ratings. For home/hobby use or powering a toy from a 9V battery you'll be fine with an eBay regulator.

author: wraper
author_rank: Unknown
timestamp: April 22, 2017, 12:53:40 pm
content: Quote from: Fungus on April 22, 2017, 12:43:04 pmReally, your own blown stuff and wasted time does not count? You could buy known genuine MOSFETs with 3-5x lower current rating and, likely, they still will be better than ebay/ali special. From my own experience, even if you get genuine stuff, very likely around 10% will be faulty, be it rejects, ESD or whatever caused them be faulty. For example I've got a batch of attiny24A with around 8% of them having faulty flash.QuoteIf the price difference is so high that it "makes sense" to buy 3x amount of the parts, most likely, none of those batches will be genuine.

author: wraper
author_rank: Unknown
timestamp: April 22, 2017, 01:03:11 pm
content: Or there was shortage of one pretty unique but cheap IC at all major distributors for a few months, had no choice but to order from aliexpress. I'm pretty sure does it not have clones. Form 250 pieces in a tape, in total around 20% were faulty. And the strangest fact was that most of the faulty ones were at the one end of the tape, being around whopping 80% faulty at one end and mostly working on another. Of course nobody bothered to properly package them as well. Guess they received some huge ESD impact at some point of time. Paid for them as much as farnell asks, so it's not like it was some known crap.EDIT: The not so fun fact was that I tested a few from that "good end" of the tape and found them fine. Under he microscope they were 100% the same as those from Farnell, package, top and bottom markings. In the end had to do hell a lot of reworking the boards.

author: Fungus
author_rank: Super Contributor
timestamp: April 22, 2017, 06:23:53 pm
content: Quote from: RukyCon on April 21, 2017, 05:11:08 pmNot a problem. Buy thousands, with confidence.

author: Seekonk
author_rank: Super Contributor
timestamp: April 22, 2017, 07:49:08 pm
content: An owner asked me to submit the paperwork for a legacy product to get CE. It was a application that clearly required X2 caps, the paperwork even asked for the certification. He told me to leave it blank. He was going to travel to the country, take them out to dinner and negotiate the acceptance. They ended the test early when almost all the samples failed. $40K down the tubes.Putting two caps in series is a pretty good substitute for X2 caps. This is their construction internally to reduce corona degradation.

author: RukyCon
author_rank: Contributor
timestamp: April 27, 2017, 11:48:17 am
content: By the way it looks, it looks like most people say no to x2 caps from eBay.

author: macboy
author_rank: Super Contributor
timestamp: April 27, 2017, 01:02:53 pm
content: Quote from: Seekonk on April 21, 2017, 05:49:14 pmYou don't need X2 caps in a dropper because in that application the cap is not directly across the line, it is in series with the load, which is entirely different. I have seen many commercial products, all listed, all with non-X2 caps in their dropper circuits.Quote from: Seekonk on April 22, 2017, 07:49:08 pm"Pretty good" isn't good enough. There is no acceptable substitute to X2 rated caps. If you need them, then you need them. The rating/certitification counts in addition to the performance.

author: RukyCon
author_rank: Contributor
timestamp: April 27, 2017, 02:53:50 pm
content: One time i found a Teapo X2 cap in a dead PSU. I found this odd since they usually make cheap electrolytic capacitors for stuff like PSU's, Mobo's, and other stuff. But i had not seen a x2 cap from them until i opened that PSU.

author: RukyCon
author_rank: Contributor
timestamp: April 28, 2017, 07:50:25 am
content: I have a LED light bulb from eBay and the power supply that it used in it [a capacitor dropper supply] was using a standard polyethylene capacitor, no x2 cap.

author: james_s
author_rank: Super Contributor
timestamp: April 28, 2017, 08:08:35 am
content: I don't think I've ever seen a X2 cap used as a capacitive dropper, those are pretty much always standard film caps.

author: RukyCon
author_rank: Contributor
timestamp: April 28, 2017, 09:06:27 am
content: I've seen them used in LED lamps for the dropper supply.

author: wraper
author_rank: Unknown
timestamp: April 28, 2017, 03:27:51 pm
content: Quote from: james_s on April 28, 2017, 08:08:35 amIf it's some cheap crappy device. In which case those dropper capacitors fail very often.

author: RukyCon
author_rank: Contributor
timestamp: April 29, 2017, 10:49:21 am
content: Quote from: Siwastaja on April 21, 2017, 04:32:24 pmI had a case where i got a 100 pack of 1w LEDs for 7$. But about 80% of the LEDs were bad. This was back is 2016.But recently i bought a 50 pack for 3$ and less than 5% were bad. [But no idea how long they will work in the long run.]It seems a bit odd that less than a year later and all of the sutten the LEDs got a lot better.

author: RukyCon
author_rank: Contributor
timestamp: May 04, 2017, 05:40:03 pm
content: I just found that in the pack of capacitors i got, most of the capacitors that are below .1uf are dead.Here are the best testing brands from best to worst:JH: 100% Test good.generic brand 1: 100% Test good.Unknown: 100% Test good.Tenta: 95% Test good.Now time for the bad ones.SR.CAP: 0% Test goodgeneric brand 2: 0% Test good.Here's a photo of the unknown one.

author: Assafl
author_rank: Frequent Contributor
timestamp: May 04, 2017, 07:12:10 pm
content: Are there unpopular values that are less often faked? E.g. Are they faking 100nF and 0.47uF and whereas 330nF being less popular is less often faked?I ask because perhaps there are values that are "safer" to buy than others.

author: RukyCon
author_rank: Contributor
timestamp: May 04, 2017, 07:50:39 pm
content: All of the 100nf and .022uf capacitors i got were dead.

author: RukyCon
author_rank: Contributor
timestamp: July 04, 2017, 05:17:09 pm
content: The seller gave me a partial refund for the dead capacitors, and so far the others are still good.Also, tenta i'm pretty sure is a good brand because i tend to find them a lot in some electronics even from bigger brands like philips and GE.