Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Renovating the wheel

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Power Saving Charger

Mechanically cut power to transformer when phone is removed
  [vote for,

Start by making a cradle-style cell phone charger.

Replace the wall-wart ac/dc adapter with an adapter integrated into the cradle.

Put a momentary switch into the cradle, which is closed when the cell phone is in the cradle, and open when the phone is out of the cradle. Run the 120V power through this switch before it goes to the adapter.

Viola! As soon as you take your phone off the cradle, the adapter ceases to draw any electrical power whatsoever, even without unplugging it.

Thus, one fewer "phantom load" wasting electrical energy and money.

goldbb, Apr 06 2009

Green charger... http://www.gadgets....-Phone-Charger.html
...it's white. And baked to a crisp. [coprocephalous, Apr 07 2009]


       I often leave chargers of any kind plugged when not used. I'm not convinced they are a "phantom load". Surely they thought of this and found some way to solve it?
zeno, Apr 06 2009

       Most AC/DC adapters do draw current when nothing is plugged in. Usually it's a couple of watts. You probably don't notice because it's not actually a lot of power, even if it does drain 24/7.   

       They need some voltage to determine whether anything is plugged in to them. There are ways of making them draw much less power to do this, but they generally drive up the cost and consumers never notice the difference. Ipod chargers draw just 0.1 watts, or so I've heard.   

       To turn it of completely you have to turn them off at the socket. Or buy appliances with the adapter built in to them which feature proper off switches. Unfortunately proper off switches are becoming scarce, as designers feel the need to replace them with standby butttons. For some reason many modern TV's have to be reprogrammed if you turn them off properly too. It's like there is a conspiracy to make us draw unnecessary power
Bad Jim, Apr 06 2009

       [zeno]: they thought of this. right before thinking 'Whatever'.
loonquawl, Apr 07 2009

       I deal with this, for what it is worth, by only every using a single pair of plug sockets for charging. This means I know where all my chargers are and I avoid ever having more than two chargers plugged in at once.
Aristotle, Apr 07 2009

       21Q, it would be very easy to make your 12V DC to 120V AC inverter turn off, using a mechanical switch in the AC outlet, when nothing is plugged into that outlet.   

       Thus, you could leave your inverter plugged into your car all the time, and it would only draw power when some AC device was plugged into it.
goldbb, Apr 07 2009

       21Q, If you wanted to design a cell charger that wasn't cradle type to do the job (i.e., the type which plugs straight into the phone), it would also be doable.   

       The cord going from the adapter to the plug that goes into the phone would have 4 wires inside.   

       The first two wires in the cord would be the plus and minus DC power, coming from the charger / adapter, and these would be connected two pins on the plug.   

       The second two wires in the cord would be a "hot" 120V AC power line coming from your outlet, going through the adapter unchanged, and a "load" 120V AC power line bringing that "hot" AC power out of the phone and back to the adapter, where it powers the adapter.   

       The latter two wires wouldn't connect to any of the pins on the plug; they would connect to each other through a small momentary contact switch, which is closed when the plug is pushed into the phone, and open otherwise.   


       However, even if your inverter shuts itself off if nothing is plugged in, and your cell charger shuts itself off it it's not plugged into your phone... the inverter will be on and drawing power as long as the cell charger is plugged into it, even if the cell charger is not plugged into the phone.
goldbb, Apr 07 2009


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle