EEVblog Electronics Community Forum
General => General Technical Chat => Topic started by: @rt on November 27, 2016, 05:50:54 am
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Hi Guys :)
Well there’s not much more to say... Title asks the question.
Particularly when the electrolyte vaporises and you can smell is strongly in the air.
Good quality caps (Nippon Chemicon).
Cheers, Art.
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Hi Guys :)
Well there’s not much more to say... Title asks the question.
Particularly when the electrolyte vaporises and you can smell is strongly in the air.
Good quality caps (Nippon Chemicon).
Cheers, Art.
I wouldn't breath that shit in, healthy or not. Wait for it to air out, but you should be able to wipe it up just fine, and throw the busted cap out. It's not poisonous enough to cause any major issues if thrown away.
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It was hard to help breathing the first breath, but was strong! :O
I know the electrolyte spray will damage a board, but I was more interested in carsonegens, etc.
and that spelling is so far off that my computer can’t do anything with it :D
ps. It was deliberate, in similar vein to one of Dave’s videos, but comparing tantalum to electrolytic.
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Most capacitor manufacturers are pretty Hush Hush about what is in there electrolytes, however I would still air out the workshop after popping a large one,
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I was told that the electrolyte used was an alkaline. It's got to be something nasty to oxidize the aluminium.
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Umm, air will oxidize aluminium. Strong alkali, eg. Sodium Hydroxide will etch aluminium. ;)
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Oops I never paid much attention in chemistry class at shool. The aluminium is also etched to increase the electrolyte contact surface area. I have heard that the main stream manufacturers use 'safe' chemicals but the dodgy maunfacturers don't pay attention to the rules.
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The aluminium electrolytic was Nippon Chemicon, and the tantalum was also high quality.
Don’t know the brand for that one, just that it came from a high quality production line.
Results pretty much as expected except for the vapour, but I don’t expect it to settle anything. It’s not like this is a normal situation.
I have Tandberg satellite receivers full of tantalums (30-40) that have been running for years just fine.
I’ve had a thru mount electrolytic explode against my hand a couple of months ago for accidental reverse connection,
but it didn’t make the vapour in the air anything like this one.
https://www.youtube.com/watch?v=MecoYFIsozM (https://www.youtube.com/watch?v=MecoYFIsozM)
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There isn't really much of anything other than water that isn't "toxic" when boiled off or burned. That said, I wouldn't panic about this exposure. You have joined thousands of other electronics people who have been present when the magic smoke is released. None to my knowledge has suffered any serious immediate health effects. There may be long term effects, but there doesn't seem to be an epidemic of cancer in our profession, so that can't be too much of a problem.
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Found this PDF on electrolytes used in capacitors. http://www.kemet.com/Lists/TechnicalArticles/Attachments/15/2008-10%20CARTS%20-%20Al-Electrolytes%20for%20Automotive%20and%20High%20Temp%20Applications.pdf (http://www.kemet.com/Lists/TechnicalArticles/Attachments/15/2008-10%20CARTS%20-%20Al-Electrolytes%20for%20Automotive%20and%20High%20Temp%20Applications.pdf)
Early one used borax or caustic soda or a mix.
Here is some more info on the process. http://www.elna.co.jp/en/capacitor/alumi/principle.html (http://www.elna.co.jp/en/capacitor/alumi/principle.html)
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The chemicals are toxic in large quantities if you eat it, or spread it all over your skin for long periods. But limited exposure, and avoiding breathing the smoke ( like the idiot coal rollers do) along with washing the skin and face after exposure very quickly is not going to result in any harm.
Wet tantalum capacitors use sulphuric acid as an electrolyte, but even in the largest ones there is very little, under 1ml, and with all electrolytics the volume of liquid id nrmally all absorbed in the paper separator in any case.
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Large capacitors from the early 70s and before can contain PCB.
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I'm pretty certain it's not toxic, but corrosive. Unless you get a whole bunch in your eyes it won't do any permanent or long-term harm.
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Large capacitors from the early 70s and before can contain PCB.
To be fair they are mostly paper or polyester foil units with an oil fill, and not SMD electrolytics. Also tend to have large steel cans with a soldered seam, and operating voltages over 250VAC, and were normally marked as motor run, motor start or PFC correction, with a smattering being designed for crash discharge in Xenon flash applications.
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Yea, my guess is that it has aired out by now, you should be fine.