Testing the legitimacy of power electronics - Page 1
Forum section: electronics / beginners

author: Belrmar
author_rank: Regular Contributor
timestamp: December 26, 2017, 11:11:47 am
content: Basically ebay and aliexpress are cheap, but usually not so reliable. What are your favorite ways to spot if a component is original?

author: BravoV
author_rank: Super Contributor
timestamp: December 26, 2017, 11:17:25 am
content: Quote from: Belrmar on December 26, 2017, 11:11:47 amIts cheap, as you said, buy one, test up to rated specification to verify, as simple as that.And no, by visually especially from the web page that the images probably were copied and copied from internet, definitely will not guarantee anything.Also even you have the physical thing in your hand, you just can not easily to spot the good vs bad/fake ones visually especially at the ICs and components nowdays.Also regarding seller's feedbacks, its only useful for reliable shipping, NOT for reliable product.My 2 cents.

author: Belrmar
author_rank: Regular Contributor
timestamp: December 26, 2017, 11:22:20 am
content: QuoteWell that would be good for transformers, but i am more interested about ic's and power transistors

author: Belrmar
author_rank: Regular Contributor
timestamp: December 26, 2017, 11:24:04 am
content: QuoteYout mean to , for eample, trace the curve and try to match it to the datasheet?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 26, 2017, 01:12:50 pm
content: By buying from Digikey or Mouser...You're welcome to create a parts receiving and inspection program, but you will quickly find you are wasting hundreds of thousands of dollars to save a thousand here and there.There is good reason why reputable sellers are more expensive yet are in no danger of dying out!And if you mean not even corporate, but for your own own few euros of projects? Give me a break, you've wasted as much value in your own time as you could ever stand to save from those sources.The economic choice is simple: find a second job to fill your time, so instead of asking questions you can afford real parts, to use in, uh, what little free time you have left.Tim

author: wraper
author_rank: Unknown
timestamp: December 26, 2017, 01:41:32 pm
content: Quote from: Belrmar on December 26, 2017, 11:22:20 amIf the price is way lower than at reputable places, most likely they will be counterfeits. As of how to check, there are some visual ways. Rough surface which look like grinded, inaccurate logo, different font, other inaccuracies in marking and package. Sometimes they may be blacktopped or grinded, then blacktopped and new marking applied. In such case it usually can be removed by rubbing with acetone or even IPA.

author: IanMacdonald
author_rank: Frequent Contributor
timestamp: December 26, 2017, 01:49:14 pm
content: A common problem is remarking of parts to make it appear they are higher specification versions than they are. In this case they're probably genuine parts, just not the ones claimed. A recent example was the remarking of XLSemi 35v switching regulators to sell as 50v versions. Since this is easy to do, it is rife.If you get something like a TIP42cwhere the 'C' looks like it's in a different typeset, be suspicious.