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Posted By: ghost307 Snake oil or great idea? - 04/27/11 12:50 AM
I recently was asked about a combination duplex receptacle and dual USB port wiring device.
It's not UL Listed based on my research to date and it looks like a doohickey cobbled together to jam 120V and 5V in the same box.
Does anyone have any knowledge of these things?
It's being hawked by a company called fastmac, which handles stuff designed for Apple products.
http://www.engadget.com/2011/03/17/fastmac-u-socket-review/
Thanks
Posted By: Niko Re: Snake oil or great idea? - 04/27/11 01:23 AM
I have heard about them but haven't used one. It seems to be a good idea at least one in every room for cell phones.

Also they are not Tamper Resistant.
Posted By: jdevlin Re: Snake oil or great idea? - 04/27/11 01:29 AM
Is the only reason for them to charge Iphones? I don't own anything that charges from a USB port. Is that a common thing?
Posted By: twh Re: Snake oil or great idea? - 04/27/11 03:43 AM
From their site: "Safety Agency Approval(s)- TUV Rheinland"

Why didn't they just get UL approval, since it's made in the USA? Maybe that was the rigorous testing they claim.
Posted By: gfretwell Re: Snake oil or great idea? - 04/27/11 07:52 AM
There is no "legal" difference between U/L and TUV. They are both NRTLs. I assume they used TUV because this was developed in Europe.

USB charged devices are actually pretty common. I am looking at 2 right here on my desk. (an MP3 player and a wireless blue tooth keyboard)
A lot of mobile devices charge on a USB port.
Posted By: Texas_Ranger Re: Snake oil or great idea? - 04/27/11 02:40 PM
Quote
I assume they used TUV because this was developed in Europe.

... or because (I think) there's a Chinese branch of TUV Rheinland...

I definitely don't like that beast! If it were a single with two completely sealed USB ports in place of one of the two faceplate openings I'd say ok, but with a mostly open circuit board and exposed USB shield inside the box? Sounds like a 120/5V crossover from faulty isolation (think nicked wire or ancient crumbling rubber) waiting to happen.
Posted By: NJwirenut Re: Snake oil or great idea? - 04/29/11 08:29 PM
Actually a pretty neat idea, although the physical execution could be improved along the lines mentioned above. Would also make it compatible with standard faceplates.

They should also rig some kind of mechanical switch that only powers up the 5V power supply circuitry when a USB plug is actually inserted into one of the DC ports. Otherwise, it is a bad a power waster as any other "wallwart" type adapter.

These would be nice in hotel rooms. Recharge phones, GPS, handheld games, etc.



Posted By: Trumpy Re: Snake oil or great idea? - 04/30/11 08:22 AM
So I take it that each one of these devices has a small transformer and rectifier behind the plate, to derive the 5V?
Posted By: gfretwell Re: Snake oil or great idea? - 04/30/11 05:10 PM
Probably a switching regulator.
Posted By: NJwirenut Re: Snake oil or great idea? - 04/30/11 05:53 PM
To meet USB 2.0 specs, each port should be able to provide 500 mA @ 5V. A small switching power supply is all that would be needed. Could easily be built inside a package the size of a GFCI receptacle.
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