Crappy power supply exploded: the condenser was like a bullet and caught fire - Page 1
Forum section: electronics / general

author: agoz
author_rank: Newbie
timestamp: June 12, 2020, 10:03:04 pm
content: It just happened to me, and I'm still kind of shocked.I had a crappy Chinese 12V/2A wall mounted power supply (for a led strip), and it exploded 1 mt from me. The case cracked in 2, an electrolytic condenser was expelled like a bullet, landed ~1 mt away, and caught fire. I was very lucky to be there and stop it!The internal circuit looks crap, plus now it's 50% burned/blackened.There was what looks like a fuse, good luck with that ;-)Now, my paranoia is kicking in, and I want to replace all no-name power supplies with quality stuff.Any suggestions about brands, resellers? I'm located in Italy.Many thanks!Andrea

author: bob91343
author_rank: Super Contributor
timestamp: June 12, 2020, 11:57:19 pm
content: If you stay away from wall mounted units you have a better chance. Since those are sealed, the manufacturer can get away with all sorts of bad stuff. One with a removable cover is a different story.Don't buy based on country of origin. Chinese stuff has a bad reputation but it's better and better as time goes by.Of course you can spend more and get higher quality.

author: bdunham7
author_rank: Super Contributor
timestamp: June 13, 2020, 12:12:04 am
content: How close to its 2A limit was it running? It sounds like maybe a rectifier shorted and exposed the cap to mains AC. That'll pop 'em pretty hard!

author: coppercone2
author_rank: Super Contributor
timestamp: June 13, 2020, 01:44:00 am
content: when I look at my box of power adapters I often see fish heads instead

author: agoz
author_rank: Newbie
timestamp: June 13, 2020, 07:35:36 am
content: Quote from: bdunham7 on June 13, 2020, 12:12:04 amQuite close (1.9A), for a few hours. In hindsight not a good thing to do, I realize.QuoteFireworksAndrea

author: agoz
author_rank: Newbie
timestamp: June 13, 2020, 07:37:49 am
content: Quote from: bob91343 on June 12, 2020, 11:57:19 pmGood suggestion, thanks!QuoteI agree. It's not about China, it's about "I will not even write my manufacturer name on it".Andrea

author: Whales
author_rank: Super Contributor
timestamp: June 13, 2020, 10:13:47 am
content: If you want quality + cheap: 2nd hand laptop chargers. It's not possible to inspect inside them without breaking them, but if you stay with OEM models that came with laptops (ie not 3rd party replacements) then you will get things designed to their upmost to avoid setting peoples' blankets on fire. 12V is less common than 19V so sourcing may be fiddly for any sort of quantity.If you want quality + easy to obtain: ATX power supplies. They are a bit bulky and you have to tuck the unused wires somewhere, but they are very easy to inspect and can be obtained in bulk. 2A@12 is nothing for them, so add a fuse in line with your LED strip in case it shorts out.

author: LeonR
author_rank: Regular Contributor
timestamp: June 16, 2020, 09:53:59 pm
content: I'd suggest taking a look at Mean Well.

author: james_s
author_rank: Super Contributor
timestamp: June 16, 2020, 11:42:28 pm
content: Virtually any of the brands you can buy from mainstream distributors like Digikey and Mouser should be fine.I do like the idea of surplus laptop bricks and similar power supplies, there are loads of good quality surplus PSUs out there, I very rarely buy one new.

author: 0culus
author_rank: Super Contributor
timestamp: June 17, 2020, 12:12:08 am
content: Solidly a "get what you pay for" thing as always. Spend a few bucks on a name brand (even if it's made in China) and it will not only be more likely to not explode (because it's properly designed) it also will spew far less EMI than shitty no name "won hung lo" SMPSs.

author: Bud
author_rank: Super Contributor
timestamp: June 20, 2020, 05:55:56 pm
content: Remember and use this rule of thumb for Chinese made electronics:== Divide all specifications by 2 ==E.g. in your case you should had used only 1A load.