Question about electricity

[Skel]

At least some of the stuff most people have plugged into their electrical outlets are laptop power supplies, phone chargers, chargers for this and that.

How do all these things suck up electricty, and does it matter if it's plugged in, even if the thing it's charging is charged? Is it good to unplug these things?

 

[baba]

It definitely uses electricity even when not turned on but still plugged in. Unplugging appliances when not in use is a good idea, but often not very practical.

 

[Skel]

It definitely uses electricity even when not turned on but still plugged in. Unplugging appliances when not in use is a good idea, but often not very practical.

No not the appliances...I meant the power suppllies. Should you unplug those.

 

[*smb]

Yes you should definitely unplug AC/DC adaptors when not in use.

 

[Skel]

Yes you should definitely unplug AC/DC adaptors when not in use.

Ok but is this because they are using electricity, or some other reason?

 

[LeoFenderBender]

If you were looking to avoid a rechargeable battery's "memory effect" a deep discharge between charges is essential. that requires unplugging from the wall until the battery needs a recharge.

It is essential to unplug your rechargeable appliance if you have a NiCd battery; metal hydride & lithium based batteries may be plugged in since they don't have as pronounced a memory effect.

 

[eedre]

The transformer inside still draws current while plugged in because of the pseudo short circuit created by the primary winding. That's not a good thing unless there is a load (phone, PC, etc.) connected to the secondary.

 

[Skel]

The transformer inside still draws current while plugged in because of the pseudo short circuit created by the primary winding. That's not a good thing unless there is a load (phone, PC, etc.) connected to the secondary.

Ok. So it's sucking up electricity AND it's hard on the unit I bet.

 

[aborgman]

The transformer inside still draws current while plugged in because of the pseudo short circuit created by the primary winding. That's not a good thing unless there is a load (phone, PC, etc.) connected to the secondary.

This would be an issue in a linear power supply, but basically everything available now is using switching supplies.

 

[PaleMelanesian]

Eh, I don't know about most. Some, mostly hi-tech items, yes, but most?

My computer - yes.
bass amp - no
phone / answering machine - no
cell phone charger - no
cable modem - no
network router - no
camera battery charger - no

Mainly things using wall-wart power adapters.

Go ahead and unplug them. If you want to be sure, try a Kill-a-Watt power meter. You can calculate exactly how much power things are drawing by just sitting there.

 

[stedtale]

Go ahead and unplug them. If you want to be sure, try a Kill-a-Watt power meter. You can calculate exactly how much power things are drawing by just sitting there.

lol, I bet that power meter costs more then you'd save in a decade of unplugging your adapters...

 

[Matthew Bryson]

I leave both of my cell phone chargers (home and office) and all of my AC adapters for bass effects, drum machine, and four track plugged in when not in use. (disconected from the device, yet still plugged into the wall.)

Maybe that is bad, but I haven't had any of these adapters ever fail and I haven't noticed any giant electricity bills from all of the extra electricity used. I like having them plugged in and ready to go.

 

[irjason]

You have something worse. You have an open wire hanging on the floor...with electricity going to it.

Not smart.

It is highly unlikely that any of these adapters he mentioned are producing anything even remotely dangerous.

 

[Matthew Bryson]

You have something worse. You have an open wire hanging on the floor...with electricity going to it.

Not smart.

I know. I could come along, and touch the end of that 9v adapter and it could be every bit as serious as touching the business end of a 9v battery.