Beware of Chongx capacitors

[maxwell3e10]

I recently got a capacitor kit with "Chongx" (Thongx?) electrolytic capacitors. All pieces for multiple values are failing at the rated voltage!

[exe]

Is it possible the + and - terminals are "swapped"?

[maxwell3e10]

No, in the opposite direction the current starts to shoot up at an even lower voltage. They maybe mislabeled, at 5V seem to be OK.

[wraper]

I've bought some "LOW ESR" caps at local shop a few years ago. Turned out to be ChongX with golden marking and suspiciously small size. ESR was crap. Checked under rated voltage and leakage current was a few mA. Which dropped a lot with a bit reduced voltage. So rated voltage was totally fake.

[Jay_Diddy_B]

I recently got a capacitor kit with "Chongx" (Thongx?) electrolytic capacitors. All pieces for multiple values are failing at the rated voltage!

Do they get hot when you test them like this?

0.24 x 15 = 3.6W

They should get hot really fast,

Jay_Diddy_B

[John B]

There's also Chengx and Changx, though I don't know what the difference is. Ie whether they are a related company or knock-offs of each other. I have no issues with a collection of Chengx ones, they are 63V and I took a few of them above 63V as a test without problems.

[maxwell3e10]

Do they get hot when you test them like this?

0.24 x 15 = 3.6W

They should get hot really fast,

Jay_Diddy_B

Yes, this is just for a few seconds, you can see it's already current limited and voltage is starting to drop. Someone on Youtube has a video blowing them up like this.

[amyk]

Maybe they need to be reformed, since they have sat for a while without voltage.

[Bud]

I recently got a capacitor kit with "Chongx" (Thongx?) electrolytic capacitors. All pieces for multiple values are failing at the rated voltage!

Frankly, I would not touch anything with such name with a 10 foot pole in the first place.

[mawyatt]

One thing that might help would be to look at the relative size of similar capacitors, this might give an indication if these are mislabeled. Capacitors with the same capacitance and voltage rating would have similar volumes.

From your images, these look small for 470uF at 16V.

Anyway, good you found this before using them

Best,

[wraper]

The ChengX is the original, all similar others are clones.

And yes, even the lower tier has clones -- as long as there is a market, and they can find even cheaper ones.

I've recently came across f*ing fake ESP8266 modules.

Wasn't Chang (Changzhou Huawei Electronics Co. Ltd) http://www.huaweiec.cn/ the original one? They were available more than 2 decades ago for sure and company supposedly exists since 1987. And then the rest appeared later AFAIK, all having virtually the same logo. Like Chong, Cheng, ChangX, ChengX, ChongX...

[jaycee]

ChongX.. like most chinese electrolytics.. only useful for firing down the garden when bored

[Shock]

Stick to the quality brands rather than Chinese rubbish. The good manufacturers will sell caps in different series and provide datasheets.

https://www.tomshardware.com/reviews/power-supplies-101,4193-5.html

[wraper]

Some tier 2 brands listed are virtually no where to be found, like Teapo and Elite.

That's not true. Teapo/Yageo are very widespread. Elite is not uncommon too and is quite often used in Dell equipment. As of Chang, I found them even in some $40k equipment, LOL.

[Shock]

I avoid buying Chinese branded and made in China products where I can. I'll stick to Japanese capacitor brands and avoid the Chinese fakes, clones, partial or nonexistent datasheets, slow delivery times and lack of warranty. I'd also much rather support local distributors here where they gather quality brands from around the world and deliver same or next day.

[Psi]

Why not replace with some of these quality caps

[madires]

Some tier 2 brands listed are virtually no where to be found, like Teapo and Elite.

That's not true. Teapo/Yageo are very widespread. Elite is not uncommon too and is quite often used in Dell equipment. As of Chang, I found them even in some $40k equipment, LOL.

I can confirm that Yageo is commonly seen in products, I even have some in my hobbyist stock. Also no problems with running them 24x7 for years, e.g. in DC/DC converters.

[Shock]

I probably shouldn't care, after all the deserted country in the middle of nowhere is not what we sell our parts to anyway.

So you won't sell me your parts because I probably won't buy them, makes sense. The only reason I don't buy much from China is I can get better elsewhere. Xiaomi Hisense and Huawei type products don't appeal to me at all. You still have the whole rest of Australia that might be interested in something, no need to end trade talks preemptively. Lol.

[maxwell3e10]

Maybe they need to be reformed, since they have sat for a while without voltage.

Reforming them actually worked! By limiting the current to a few mA at first and then running them for a couple of days I can get the leakage current to about 1 uA at rated voltage. But the capacitance values dropped to 60% of the nominal value! I don't think it's really "reforming", but forming them in the first place. From what I read a capacitor usually undergoes voltage soak at the end of manufacture.  Not sure if they are skipping on that step to get higher capacitance or it was just a bad batch.

[Vovk_Z]

From your images, these look small for 470uF at 16V.

+1, it looks like 47uF 16V size, it must be 470 uF 6,3V max.

[maxwell3e10]

Yes, it's 6.3x11 mm size and for this size the largest capacitor I see listed at 16V is 330 uF. And guess what, after reforming 470uF turned into 300 uF. So there is no free lunch.

[Zero999]

Stick to the quality brands rather than Chinese rubbish.

Most caps you get from consumer gears are Chinese. Funny you have not been "shocked" for years of using them.
And the Tom's HW post is 100% utter BS. Most caps you get from consumer stuff fall outside category 4.
Some of those out of category ones perform between tier 1 and 2.
Also some tier 4 ones like Lelon should be at least tier 2 in its specialty (solid state).
Some tier 2 brands listed are virtually no where to be found, like Teapo and Elite.

The good manufacturers will sell caps in different series and provide datasheets.

Chinese suppliers do the same. You just need to find them and read Chinese.

You can't blame westerners for not trusting Chinese capacitors. No doubt there are plenty of decent Chinese capacitor manufactures and indeed most of them will be genuine. The problems are there are so many brands, with strange sounding names no one in the west has heard of and there was the capacitor plague scandal of the early 2000s, so the high index of suspicion is perfectly understandable.

If one is prototyping, building small volumes, or the product has a high mark-up value, there's no need to use unfamiliar brands. Capacitors are cheap and there's no point in trying to skimp on them. I'd rather stick with capacitor brands I've used before without any problems, than some unknown brand. Perhaps if it was a high volume consumer product, it would make sense, but I'd subject large samples of different batches for intensive testing first.

[jaycee]

All I know is what I see when I repair equipment.. CapXon, Teapo, ChengX, G-Luxon, all sorts of cheap Chinese crap, usually leaked and bulging all over the place hence why the thing has stopped working. I can count on one hand the number of times I have seen a Japanese or other quality manufacturer's capacitor exploded, and that has usually been from a failure elsewhere in the circuit which has caused overload.

Personally, I tend to use Panasonic.

[Shock]

I tend to use something in between more expensive Western brands and cheap Chinese shit.
...
You get what you paid for when bidding for the cheapest option.

It seems we both dislike cheap Chinese products and fakes.

Blueskull, you do not yet realize your importance. You have only begun to discover your power. Join me, and I will complete your training. With our combined strength, we can end this destructive conflict and bring order to Shenzhen.

[uer166]

@blueskull, this has always intrigued me, I have absolutely no problem using Chinese made components/capacitors, but was always lost on how/where to find the right components. How do you figure that "series X" from "manufacturer Y" has repeatable performance at a good price, vs. obliviously fake ratings like the OP's case. Obviously using Panasonic from Digikey guarantees success 99.99% of the time, but as you said, something 10X cheaper at similar performance is indeed available.

I feel like this is as much an education issue as it is pre-concieved notions and biases. Say I want a 47uF, 100V, 0.5A 100kHz ripple electrolytic. How do I go about finding a (reputable) Chinese brand with a good track record. And further, how would I go about getting a reel of them to an assembler?

From my experience, many components in US automotive products come from unknown-to-the-public Chinese suppliers, and they perform great at a competitive price. Considering automotive is a low margin business, this is essential. Not only that, but the suppliers are more willing to cater to custom requirements than big-name well known brands.