Core77

I'm no engineer here. But I would guess that they mean that the embedded transformer needed to convert the 120VAC voltage to 5 volts needed for USB is only activated when you plug in a cable.

With the regular wall socket, there is no conversion needed, as you would connect straight to 120VAC wiring.

A constantly on USB port would be kinda like having a phone/laptop charger plugged in to the wall, yet not into your laptop. It's constantly on and using energy regardless of being plugged into your device.

Presumably, the point is that they went out of their way to make sure the USB ports *do* function like normal electrical plugs, rather than the power vampire they'd be if they were wired like a traditional USB hub plugged into the power grid.

I think they are saying that they didn't do something like shrink down a powered USB hub and shove it inside the outlet (where the hub would be pulling power continuously).

I would assume they mean the USB ports don't use any kind of transformer or capacitor to convert the power, which would use a small amount of power even when nothing's plugged into them.

Regular plugs don't draw power unless the circuit is completed (maybe a short would draw power.) But maybe USB plugs normally draw a little bit of power unless it's designed not to draw power?

I always thought that any plugs with a large box plugging into the wall is constantly trying to vampire electricity from the wall.. but again, I'm not sure

USB is DC, I imagine they were trying to avoid the power vampire issue seen in other DC converters such as those used to charge laptops and mobile phones.

Some older designed chargers would use a small transformer; this would draw a small amount of power, even when not being used, like a piece of equipment being on stand-by. The USB charging in this sockets could be like modern mobile phone chargers and have a switch mode power supply that only draws power when the phone is connected to it???

Power adaptors do draw a small amount of "parasitic" power when plugged in, even if the thing they are powering isn't plugged in to it. It's great that the designers of this outlet decided to make sure that the USB adaptor built-in to the outlet doesn't do this. Off to place my order...

The way I understand it is that regular plugs create a physical connection letting the electricity through, therefore no waste while unplugged.

The USB connection needs an adapter to bring the power down to 5V just like an external power brick would do. This is what continually wastes power even if not connected to a device. The power wasted is from conversion inefficiency (~70-80%) which is converted to heat.

I think the product description is talking about the transformer used to tranform main power (110/220V) to USB (around 4/5V). A plugged-in transformer will draw power independently of the device usage, so a mechanism that would disconnect the transformer from the main would prevent it from "leaking" power... at least that what I understand with my very old/poor electricity knowledge :)

I believe this more a reference to standard USB ports, which need to be actively powered so they know when something is plugged into them

Hi there. Normal plug sockets don't use power. However the USB ones will require a transformer as you don't want 110v/240v going into your USB devices!
Normally, transformers plugged into the mains DO suck constant power, but it seems this one has some circuitry to prevent that. That's my take on it anyway.

USB ports supply DC power which means they must have some sort of power supply inside the outlet to convert AC power to DC.

Most of the time DC power is supplied to our devices via wall warts that continuously draw power so long as they're plugged in. Somehow they are switching the power supply off completely when nothing is connected to the USB ports so that is doesn't continuously draw power.

Normal plugs do not have any vampire power problem. ...

However the circuitry in this device that converts the 110 volts to 5 volts is the same type of circuitry found in the typical wall wart charger. Most of those chargers will continue to draw power whether a device is charging or not. It's great that they designed this so it didn't have that problem. ...

Personally though, I would have liked to see this designed to fit into the standard Decora wall plate format. If they'd only provided a single AC socket, they could have easily fit two USB outlets above or below.

Yes, regular outlets do not leak power. But, a USB outlet will require a transformer to knock the 120V down. Transformers typically bleed off energy (heat and sound) whether anything is plugged into them or not.

Your correct, a plug-less outlet will not draw power until you place a plug into it that needs power.

However, you need to think of this unit as 2 separate electrical units (now joined): 110V plugs and 5V USB ports. To work the USB ports, 110V need be be stepped down via a transformer to 5V .... that process would normally draw power (even without a device been plugged in). I'm presuming that the designers placed a "switch" into the unit that turns off the transformer until such time as a USB device is plugged in. The picture of the unit appears to show an indicator light/port (upper right) that presumably comes on once the USB port is in use.

Re: Vampire ports

The electricity supplied to your home (which is what comes out of a standard power socket) is ~120 VAC, but a USB port needs to deliver 5 VDC, so there must be a transformer and some sort of rectifier to step down the voltage and convert AC to DC. These circuits are traditionally lossy (like how a plugged in wall-wort DC adapter will be slightly warm even with no device attached to the other end).

In this case the manufacturer is claiming their designs doesn't waste power on the electronics behind the USB port -- they probably only power on when something is socketed.

They are probably talking about the tranformers that transform the 120V to 5 V. All transformers use power even though nothing is plugged into them, that's why a transformer gets hot even though it"s not in use.

Your typical wall plug does not use any power when nothing is plugged in. It's the USB power conversion that could constantly suck power.

Very cheap power adapters, generally big wall-warts, will use electricity even if nothing else is plugged into them, quietly turning electricity into waste heat. Higher quality/more expensive adapters behave as quoted, only drawing power when there's a reason to, which is great for in-socket devices since they're always plugged in.

I think at least 50 more people need to post here about how regular outlets don't suck extra power but USB outlets, with a power transformer, could. At least 50 more (maybe 100).

On the other hand, how useful is technical information from people who can't read??

Honestly people.....

Hahaha. The product description is pretty bad... I mean they could of mentioned that it doesn't consume any power while in use but to state that it is one of their main design priorities is a bit over the top. I'm hoping that's the result of marketing employee and not their engineers...
Basically in your standard outlet when nothing is plugged in you have an "open circuit". There is no current flowing and hence no power (for simplicity sake, assume power equation is P=V*I ).
Now... what they are doing here is aside from providing you with your standard AC they are providing 5Volts DC for the USB. This is usually what your "power brick" or "wall-wart" is doing. So basically stepping down the voltage and rectifying it... since USB devices draw significantly small amount of current they are able to accomplish this by using solid state devices, 'chips' or little microcontrollers. We have recently shrunk this technology considerably, remember the old iPhone charger compared to the tiny new one? (your macbook charger is still big because of the larger current requirements). So you have to power this chip and even with no load attached to it, could potentially be using small amounts of current depending on the specific chip to stay in some form of stand-by or active state.
I would take this discussion in the direction of the new "smart-home" devices coming out. In order to monitor all the electricity in your home, technically point out where you can save and such... but we have to keep in mind that in order to monitor this we have to waste power... kind of a catch22. Of course one can argue that this might be a negligible power consumption but I would like to see the numbers, especially when we are talking about a good couple dozen of outlets in a home, couple hundred on your street and hundreds of thousands in your city... is the "smart-home" so smart?
Sorry for the long post and tangent but then again... I am an Electrical Engineer...

@DJ: maybe you now realise that we all replied to the question asked by the author, while other comments were still being moderated? :)

Went to the ordering site at fastmac.com. They keep moving the shipment date forward every month (they've been doing that for 4 months), and there's no indication that this product will ever ship. Worse, they bill your Paypal immediately. AND, they require "registration" to use their site. AND, the product isn't available - even as a pre-order - from any reputable site, i.e. amazon.com. Seems more and more like a scam to harvest contact and Paypal info.

KGB was correct. Nuff said.

These are available in various guises for Uk and US styles of mains, as well as including USB. Hunting will also reveal USB only sockets - sans mains sockets.

I'm not saying where though, as u am going to be reselling them online soon! C'mon get some!