Do Power Bricks Draw Power - AC/DC

[mobiledynamics]

Someone may know the easy answer....power bricks, whether it's the brick that powers a small laptop charger, etc.

Do they use power when not in use. Or the better ones don't and some may do ?
I never really checked them but it so happened I had a USB C 130W one in use......and it was pretty warm. I suppose it boils down the heatsink design that comes into play

 

[teamextreme]

Short answer, yes. How much depends on the size and mfg. Typically a pretty small draw though.

 

[mobiledynamics]

Gosh. Off to start plugging in devices into my various chargers/etc to compare.

I am very careful about these things anyhow - no generic off name junk. Still weary though...

I have various *bricks* of sorts plugged in. Combo USB / USB C with cables I have on the desk or even under the living room couch plugged into a floor outlet, etc.

 

[Mr. T]

In the imperfect world that we live in they all will use some current even when nothing is plugged in to them.

It takes work to convert one voltage to another and AC to DC. Because there isn’t currently a way to have 100% efficient conversion, some of that work will be converted to heat.

I wouldn’t worry too much about a “brick” that is a little warm when being used. But being too warm or more importantly “hot” to the touch when nothing is being charged could be a sign that it’s failing.

 

[outdoorspace]

More than you probably want to know about power supply efficiency...
https://www.digikey.com/en/articles...iciency-standards-for-external-power-supplies

The old wall warts were not SMPS type and waste a fair amount just plugged in.

On newer supplies look for "Level V" or better on the label.

 

[MoonRise]

Short answer (as mentioned ) - yes.

That power usage of something being just plugged in is also sometimes called "vampire power usage ".

 

[SGKent]

yes - Once a year I go outside and turn off all the breakers, then turn on one at a time to see how fast the dial spins. If it spins too fast it could be an old radio or power supply causing it sometimes. There are also plug in devices that tell you exactly how much power things in your house draw when off. You'd be surprised to find out that some things in standby mode might cost you $40 a year in power. Multiple that times 4 or 5 devices and that is a lot of money over a 10 year period.

 

[mobiledynamics]

The only wall warts I think is probably around my tv area's where I have a IR emitter block and also a wall wart for a 5 port network switch...Heat was never a concern for me on those things.

But boy, after observing how --warm-- the laptop brick got, it's on my wiki to observe said other bricks and how hot or not they get and for how long (even after the source has been unplugged).

With the proliferation of USB C as a somewhat standardized plug....I'm replacing the smaller power 5 port usb a/usb c in 2 areas (under couches with cables underneath for easy access) with a 100W Dual USB C/Dual USB A .

 

[MoonRise]

Get a Kill-A-Watt meter and an IR thermometer.

Check things out and you can thus actually measure the power usage and the temperature of the wall warts or power bricks or your TV or computer or whatever when it is on 'standby' and when it is in use.

Knowledge is good (was going to say 'knowledge is power', but we're trying to measure the power and have that knowledge. )

 

[mobiledynamics]

yeah, I have both clamp and also a makeshift SO 5-15R/P cord setup with the insulation cut open for instances where I want to meter something.