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Cheap USB chargers

Posted: Tue Jun 26, 2012 5:51 pm
by cashaw
I guess it's not a direct result of the RPi using a USB charger as a power source, or Youtube's Mikes Electronics demonstrating the problems with power load on a cheaply constructed Chinese USB charger, but there does seem to be a lot of focus on the problems of using cheap USB chargers to provide their specified current at a correct voltage.

Tonight I visited my local electronics catalogue store (Kjell & Company in Stockholm) to buy a new charger to replace my spare telephone charger which has been powering my Pi for the past few weeks. I had selected one which was small, cheap and specified at 1000ma, but when I went to order it the assistant said that it (and a number of other similar USB chargers) had been withdrawn from sale and sent back to the suppliers. The reason being that they did not meet the requirements of the CE certification and could be dangerous under certain conditions. The assistant pointed me towards a more expensive, larger but better built charger which suited me fine !

I had never thought about USB chargers before buying the Pi, and have spent far too much time thinking about them since :lol: but it's good that because of the increased awareness of the problems with bad quality chargers that perhaps the industry is starting to act ?

Re: Cheap USB chargers

Posted: Tue Jun 26, 2012 6:29 pm
by cashaw
Any reason it doesn't allow me to edit a post after posting ? I often have to corrects spelling after posting...

What I meant to add was -

USB chargers are designed to provide high current over a short time whilst charging a phone, whilst the Pi is potentially pulling high current 100% of the time. So using cheap chargers for the Pi running 24/7 could overload a badly designed charger causing it to overheat or worse. So I guess it is a good idea to spend a little more on buying a good power source for the Pi

Re: Cheap USB chargers

Posted: Tue Jun 26, 2012 7:19 pm
by Jim Manley
You can only edit a post for something like 30 minutes after posting, and then it's cast in stone (I'm not sure whether editing resets the 30-minute clock). It may also not be possible to edit it once someone else has commented on the thread after that post, even within the 30-minute limit.

As for excessively cheap and substandard Chinese products, I just saw a news report that business is booming in China for manufacturers of children's food and products made outside China because of the lead paint on Chinese-fabricated toys, toxic plastic powder used as filler in Chinese-made baby formula, Chinese-manufactured drywall that emits harmful sulphuric fumes, Chinese schools and apartment buildings constructed of concrete without reinforcing bars in earthquake zones, etc., etc., etc. The Chinese population doesn't trust their own government and manufacturers ... caveat emptor ... let the buyer beware.

Re: Cheap USB chargers

Posted: Tue Jun 26, 2012 11:04 pm
by donde
I found my Garmin GPS charger is a 5 volt, 1 amp switching regulator charger. It has a mini-usb plug. Looking on the net, I sent for a micro-usb to mini-usb adapter for $1.46. It just got here today. Perfect!

Re: Cheap USB chargers

Posted: Tue Jun 26, 2012 11:22 pm
by mahjongg
could you post a link to the youtube video, I seem to recall seeing it, but cant find it back.
As I recall it was quite illuminating to see what kinds of junk there are on the market.

Re: Cheap USB chargers

Posted: Wed Jun 27, 2012 5:49 am
by cashaw
here you go, interesting viewing indeed !

http://www.youtube.com/watch?v=T88ej64aXUM&feature=plcp

Re: Cheap USB chargers

Posted: Fri Jun 29, 2012 12:12 am
by mahjongg
Yes that was it, and on a second view I am even more disgusted that this piece of junk was actually mislabeled as if it could power an RPI, or the USB hub it came with (which is probably also a pile of steaming "chips" inside...). You are actually lucky if it was able to power a single USB mouse. Not that it would be safe to do so!