Do dock chargers draw power while not in use?

[yoda313]

So do dock charges use power if they are plugged in but not charging anything?

Example - if you have a dock charger and its plugged into the wall but you are not charging a device does it still draw power?

Is it better to unplug charger power bricks from the wall while not in use? I was thinking of digging up a ratty old unused power strip and combing some of my power charger units. However I would not leave it plugged it if it continues to draw power while plugged in.

Thanks for any answers - or guesses [/list]

[betwixt]

Almost all devices still draw power when plugged in, even when not doing anything useful. Normally the amount of power they consume is quite low though until you actually dock the device and start charging from it.

Note that the power rating on devices is the MAXIMUM they use when under MAXIMUM load unless it says otherwise so don't assume its what they always use. Its common to see environmentalists adding up all the maximum ratings to tell you how bad you are at energy conservation. Thats like saying everybody drives at 120 MPH because thats what their speedometer dial has printed on it. If you really want to know how much energy you are wasting by leaving things plugged in, get one of those power meter adapters that show the amount on a small LCD and try it on each piece of equipment, both idle and when charging.

Brian.

[Noahtuck]

Yep,
Pick up one of these

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93519

[M Bruner]

The main thing causing the power drain is the current converter. Your item that needs to be charged needs DC current, but the electricity from your house is AC. The converter changes the AC to DC. The house current the circuit on your charger is always on, while the portion the that charges you unit only needs to come when it's connected to your unit.

[Steve Stepoway]

A friend of mine tested a number of "wall warts" a few years ago and found that their efficiency was so low that they drew almost as much power with no load as they did under load. That was a few years ago, but I doubt it's changed very much. If it's warm plugged in but under no load, then it's drawing (and wasting) a lot (relatively speaking) of power.

Steve.

[Noahtuck]

Yep!!

I started doing this also.....

A few months back a buddie of mine told me his wife brought home some switchable power strips to put on their TV's & PC's
He was like what for ??

Well, he ended up hooking them up so when they went to bed, gone for the day (work) ect. they would turn off power to everything that was not being used while they were sleeping or gone, effectively unplugging everything.

Their electric bill instantly dropped $30.00 a month and they only have 2 pc's and 3 tv's.

[yoda313]

Thanks everyone.

I think I'll use one of those power strips with the off button. That way I can still combine the chargers on one strip but have a master off so they don't stay active.

[Noahtuck]

Well how many wall warts do you have

I have one, for my cell phone, and even then i only throw it on the charger once every two days at most, and then just for the night.

But as soon as i get up in the morning and disconnect it from the charger, i always pull the charger out of the wall.

The only other thing i have that need's to be charged is my mobile mp3/video player & that charges from my USB connection to my pc.

[redwudz]

A simple test for your dock charger, see if the power supply is warm to the touch when nothing has been plugged into the dock for a few hours. If it is, it's burning up watts somewhere by producing heat.

[betwixt]

Its worth adding that most modern PCs have two power supplies although usually inside the same box. One is the main one for powering the processor, disks and memory, the other is for the standby control and USB sockets. The standby control has to be permanently ON so it can monitor for the power button being pressed and enable the main power as necessary. It also keeps all the USB peripherals powerd up too, even when the computer is apparently turned off. You can actually consume quite a lot of power into USB devices 24/7 without even realizing they are pwered up.

You need a power monitor to see exactly what is being used in standby but as a rule, assume it is a few Watts, probably as much as several wall warts at once.

Brian.

[TBoneit]

Be sure to use a power strip to avoid wearing out the power outlets in the wall. That is the biggest problem with Green advocates that say unplug everything. The charge for the electrician to come replace the outlet will eat up any $avings.

Unplugging DVRs can lead to a delay in being able to watch TV. Up t0 5 or 10 minutes depending. Missed timers etc. They are designed to stay on.

Anything that turns on with a remote is consuming power. Anything with a clock display or timer function such as a Microwave or Coffee maker consumes power.

How far you go depends on what your irritation level is. Mine is low and re-powering things irritates me so.... I'm not green.

My Green things go as far as having a job that is a 5 minute drive on mostly 25MPH local streets, driving a old car since it works until it can't be fixed. Last year I went a whopping 1500+ miles for the year. And of course getting a faster computer so it can do more in less time. I used to have to leave the Old P4 3.0 Ghz running overnight for encoding. Now the Q6600 knocks it out much, much quicker so it never runs overnight. I do pull the power on the computer but not to save energy, I do it to save fixing it after a power surge damages it.

OTOH I did replace regular incandescent light bulbs with flourescents. Mainly to avoid having to change them so often.

[gadgetguy]

A power brick is a very simple device consisting of a transformer and, if converting to DC, a rectifier. A transformer is basically 2 coils of wire in close proximity so that when one is energized, current is induced into the other. The primary coil of the transformer when plugged in is a complete electrical circuit and therefore is drawing power, whether anything is connected to the secondary coil or not. I've never measured, but I would be very surprised to see any significant difference in power consumption whether the device to be charged is connected or not.

[betwixt]

Your description of a power brick is a bit outdated. Yes, there are still transformer types around but the majority of new ones use switched mode power supplies (SMPS) because they are cheaper to build and give more Watts per ounce. Hold an AM radio near the brick, if it gets blanked out with whining and buzzing, the chances are its a SMPS type, transformer types generally (but not always!) produce very little interference.

With both types, the power drawn is roughly proportional to the load you put on them. There is a constant residual power demand as well which is higher on transformer types than SMPS types. Both tend to take a surge of power when first plugged in with SMPS normally taking a sharper 'spike' of current. Typically transformer types will be around 75% - 80% efficient and SMPS around 90% to 95% efficient.

Brian.

[thecoalman]

Be sure to use a power strip to avoid wearing out the power outlets in the wall. That is the biggest problem with Green advocates that say unplug everything. The charge for the electrician to come replace the outlet will eat up any $avings..

In the event you wear the outlet out in few years you can go buy a replacement for few bucks and replace it your self. It's not rocket scinece and only a few screws, you only need a flat tipped screwdriver. This would take even the complete novice a few minutes to complete. Just be sure to note which wires are attached before taking them off. Also be sure to turn the breaker switch off and test the outlet for power before taking the plate off.

http://www.acehardware.com/product/index.jsp?productId=2665480

Go buy yourself dinner at a nice restaurant for the $100 you just saved yourself.

[AlanHK]

So do dock charges use power if they are plugged in but not charging anything?

Touch it. It will be warm, or even hot. Thus it is using energy.

[AlanHK]

Be sure to use a power strip to avoid wearing out the power outlets in the wall. That is the biggest problem with Green advocates that say unplug everything. The charge for the electrician to come replace the outlet will eat up any $avings.

Aren't wall outlets switched where you live? That's standard in Australia, at least, and in other places just pay about $1 more for a switched outlet. Trivial to install yourself. (May not be legal, though.)

[thecoalman]

(May not be legal, though.)

That's laughable no matter which way its installed. The wire is attached via screw. Attach wire to oulet, tighten... Truthfully you'd have to be a complete nitwit to screw it up. (pun intended). FYI, I don't know how wall outlets are isntalled elsewhere, the above applies to the U.S. but I'd imagine it can't be much more different no matter where you live.

3 screws:

[RabidDog]

I think extending the life of something, like a car, can be the greenest thing you do, especially if you do lowish mileage. I would have thought its inevitable that wall warts/chargers consume power while plugged in, its just how much. Strangely my recorder is trumpeted as being gReen, but if you look at the specs, it consumes 3w in standby, thats 50% more than the previous model.
I want to know the cash cost tho eg wallwart left in 24/7 ..costs me £0.17p / £1.70p / £17.0 per day..
And where are the Deep Greens, who have downsized their TV's?? know anyone who's done that...

*I have given up my car tho (well, had it taken away)

[gadgetguy]

This would take even the complete novice a few minutes to complete.

You would think... but I can't tell you the number of times I've come across receptacles miswired, with the hot and neutral reversed.

[TBoneit]

Be sure to use a power strip to avoid wearing out the power outlets in the wall. That is the biggest problem with Green advocates that say unplug everything. The charge for the electrician to come replace the outlet will eat up any $avings.

Aren't wall outlets switched where you live? That's standard in Australia, at least, and in other places just pay about $1 more for a switched outlet. Trivial to install yourself. (May not be legal, though.)

The only outlets that are switched are the ones that are lighting circuits designed for lamps to be pluggged in. They use a wall mounted switch.

I seem to remember som COmedies from the UK where they did use a switch on the outlet. The only swutched outlet in the house where I am is on a three way switch so it can be turned onor off by the front door and then turned on or off by the door out of that room. All the other outlets in the house are unswitched and are always energized.

To the other poster, yes it is easy to change a outlet or switch if the person has any kind of mechanical skills.

However I would never suggest to someone to do it themselves in certain areas where Aluminum wiring was used since there is a problem if the use a outlet designed for copper wire.

Too many people looking to get rich via lawsuits instead of hard work.

[TBoneit]

This would take even the complete novice a few minutes to complete.

You would think... but I can't tell you the number of times I've come across receptacles miswired, with the hot and neutral reversed.

not to mention open grounds.

[mpack]

I seem to remember som COmedies from the UK where they did use a switch on the outlet.

The outlets shown in AlanHK's pic (which you reproduced) are UK style outlets, which were introduced in the UK in the mid 70s. I think the main change compared to what went before is that these plugs include a built in fuse (typically 3A,5A or 13A, depending on the appliance). Before that the plugs had three round pins and no fuse. In my lifetime the plugs have always had three pins (ie. it always included an earth). Wall outlets can be switched or not, usually they are switched.

In the 90's there was a movement to get the UK into line with the rest of the EU (plugs have two round pins, no earth, no fuse). That movement failed to find favour among the general populace...

[AlanHK]

The outlets shown in AlanHK's pic (which you reproduced) are UK style outlets, which were introduced in the UK in the mid 70s. I think the main change compared to what went before is that these plugs include a built in fuse (typically 3A,5A or 13A, depending on the appliance). Before that the plugs had three round pins and no fuse.

Actually, that style is nominally 13A, fused.
There are also 5A, unfused, with 3 smaller round pins, and 15A, unfused, with 3 large round pins -- I live in Hong Kong which follows UK wiring standards, mostly.
Older homes seem to use unswitched sockets, newer ones usually switched.

In Australia, all domestic sockets are 3 flat pins, unfused, almost always switched.
The sockets in my father's home are going on 50 years old, no sign of wearing out.

It's only in third world countries I've seen 2-pin, unearthed sockets.

[betwixt]

RabidDog,

the cost is worked out by: (load / 1000) x cost per unit x hours in use.
The load is in Watts, the cost per unit and the result are in whatever unit you pay your bill in.

For example, a 100W load used all day using the costs here:
(100 / 1000) = 0.1
x cost per unit (here it's 14.7p) = 1.47p
x 24 hours = 35.28p (£0.3528)

If an appliance is rated in VA instead of Watts, treat the VA as though it was Watts, its just a different way of quoting the power being used. You can get the unit cost (cost per KWh) from your utility bill.

Don't forget the real cost is the total of all the appliances added together.
Brian.

[mpack]

Actually, that style is nominally 13A, fused.

13A is the nominal maximum load of the plug and wall socket. But, if you want the fuse to protect your appliance then the fuse has to be matched to that appliance. If an appliance typically only draws 1A then a 3A fuse may protect it (and the user), a 13A fuse may not. In recent years most appliances sold in the UK come supplied with power cords which have moulded-on plugs, already fitted with the correct fuse.

The other plugs you mention are not used in the UK.

(Edit). Oh yeah, I was thinking about where I've seen wall outlets in the UK that were not switched. Although this is "installer choice" and could potentially be fitted anywhere, unswitched outlets tend only to be used when the appliance will be permanently plugged in, the appliance has its own switch, and the socket itself will be inaccessible. For example I have a socket like this hidden behind my kitchen cabinets, with the built in cooker plugged into it.