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Old 15th September 2007, 09:32 PM   #1
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Default Made in China buyer beware...

There are a number of sellers on Ebay selling cheap tube caps from china. The image below has a couple of the ones I bought. I got a big box of them since they were cheap. When I actually got the caps, I was like, these seem a little small to have the ratings that are on them - 1000uf 450V. Now, they all tested OK - and pretty close to 1000uf. However, at 400V they will get red hot and spew their guts in no time at all < 30 minutes. I've done this with quite a few to verify that it is indeed the batch that is bad and not just one or two. So, I reeled in the voltage and have found that at 200V these only get slightly warm to the touch and seem to be OK. Now, for the price I paid, 1000uf at 200V is still a good deal. However, if you are planning on using these (remember space wise you'd need four of these to get close to the actual value that's on the package! ) you need to factor that in - it could ruin a layout you've already cut for instance. These have legitimate markings if you go to the nippon chemi con site, but still given that they aren't what they say they are... I can only think they are fakes. YMMV - but consider this the if it sounds too good to be true it probably is warning. I'd also be interested to hear if anyone else has had problems or success with these cheap caps...
Click the image to open in full size.
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Old 15th September 2007, 10:32 PM   #2
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I can't tell from the photos- it's Nippon Chemi-con, with an i. the photos look like Nippon Chem-con, and it's common for fakes to have subtle spelling errors. Look close and see which it is.
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Old 16th September 2007, 01:58 AM   #3
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the weird spacing between the letters in the words "negative and b lack" for example might clue you in, but maybe not..
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Old 16th September 2007, 02:16 AM   #4
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Quote:
Originally posted by Conrad Hoffman
I can't tell from the photos- it's Nippon Chemi-con, with an i. the photos look like Nippon Chem-con

In the photo (I blew it up using control key + scroll wheel) it is chemi-con.
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Old 16th September 2007, 02:21 AM   #5
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Pick one and take the outer coating/surface off. Sometimes if they're fake they're just relabelled caps - kinda new shrinkwrap.

And can you measure their ESR? Should be within stated tolerance.

Lastly I worry about it being warm at 200v.
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Old 16th September 2007, 03:02 AM   #6
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According to the Mfg. catalog, the largest standard value for a KMG type cap at 450v is 47uf. That should raise suspicion...
http://www.chemi-con.co.jp/pdf/catal...g-e-070315.pdf
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Old 16th September 2007, 03:03 AM   #7
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Maybe this is how it really should look:
Attached Images
File Type: gif capa.gif (28.0 KB, 1744 views)
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Old 16th September 2007, 03:07 AM   #8
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its all the lead paint, poisoned wheat gluten and antifreeze toothpaste they use for the electrolyte!
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Old 16th September 2007, 04:47 AM   #9
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Hey all.. it is spelled correctly. Spacing is not so far off as to call it weird, it is after all a shrink wrap plastic outer case.......

And it's a no brainer at this point it's not the proper label... either real or not real. I did indeed remove the outside cover before i posted, they are plain aluminum underneath... not relabeled. As for warm at 200V... i mean maybe 100 to 105 F... just warm enough to be noticeable. Which yes is warmer than I'd think proper.. but seems stable.. so far. At this point, I can afford to blow them up - they are useless to me at the stated value.. so I might as well try to find a point I can use them, right!? Anyway.. Im sure im not the only one who's picked these up off ebay.. so anyone else have any feedback?
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Old 16th September 2007, 05:06 AM   #10
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Quote:
Originally posted by bobgroger
According to the Mfg. catalog, the largest standard value for a KMG type cap at 450v is 47uf. That should raise suspicion...
http://www.chemi-con.co.jp/pdf/catal...g-e-070315.pdf
By that.. they are really 1000uf at 100V!!! wow... what a difference!
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