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Unplugging household devices regularly

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bacon4life

Electrical
Feb 4, 2004
1,511
I have a couple of acquaintances that unplug almost every household plug and cord connected device between uses. This includes lamps, electric blankets, computers and toasters that are used everyday.

Are typical American plugs designed for this high level of use, or will the repeated use eventually cause the contacts to wear, thereby leading to a higher fire danger than if the devices were left connected?

Note, some of these devices are also plugged into a power strip, which they will turn off and the unplug everything from it.
 
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They have no switches on their devices? Or do they think that all devices are like TV sets and computers (with stand-by mode?).

Plugs and receptacles definitely have a limited number of mate/unmate operations. The cable and cable entry is what goes first, though. And when the strands have been broken to the extent that they can't carry current without overheating, you certainly will have a fire. Many fires start because of loose wires in plugs or reduced conductor area due to too much flexing during plug/unplug.

Why do they do that? You asked them?

Gunnar Englund
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
 
That habit sounds a little like "OCD". As Skogsgurra said, someone probably thinks that there is some standby load being fed if left plugged in. This does nothing but wear out the plugs, the contacts, while they will wear, are probably not going to be the problem, it will be the cord at the cord/plug joint. This quickly gets stressed and the constant flexing and pulling tears the stranded conductors to the point of failure. When enough current tries to flow through a few strands, that is when things get very warm very fast.

If they want to disconnect power to PC's or TV's, then a power strip with an off switch will do. But for lamps, toasters, etc..., it's a waste of time and will wear out the cords.
 
I don't remember the statistics but there was for a while a lot of toasters catching on fire. They were the ones with plastic cases (metal inside where the bread goes). Maby some people know someones who's house burned down or something that leads them to unplug things.
 
I hadn't heard of this in years.

My grandparents (I'm 56) routinely upplugged any electrical device that wasn't hard wired because "electricity is dangerous".

It drove my Dad nuts because he had to fix the plugs and outlets which wore out. Even his electrical engineering degree didn't convince his parents that electricity didn't pose a threat warranting unplugging appliances.

Dan
 
This is common in central America. There are good reasons.
Poor wiring methods, faulty repairs, overloaded conductors, oversized breakers, the list goes on.
respectfully
 
Why not use the switch on the powerstrip as an electrical disconnect? If that is unsatisfactory, why not two in series? The constant mechanical wear on the contacts could cause the plug to heat up and cause a fire (this has happened to me). The same thing can happen to a switch, but you will get many more cycles out of it. If you dismantle a common 120V American plug, you will see that they are made to be quite inexpensive and therefore will not take that type of abuse for long.
 
Thanks for your replies, sounds like I have some education to do.

Yes the devices all have switches. I have heard recommendations to turn off unused VCR's and the like due to the standby losses, but that didn't come up as one of the reasons. The reasons stated were that they were worried about fires and that there parents always did it.

One of them also turns off the water to the washing machine after each use because an acquaintance had their house flood from a broken hose. Any idea how many duty cycles a water valve can take?
 
In Tamp Florida, where they get a LOT of lightning strikes, they have billboards reminding people to do this exact thing. maybe they lived there once or know someone who does/did.

Also, from my experience having worked breifly for Emerson when they were making power tools and small appliances for Sears, the absolute cheapest junkiest component in the entire system was almost always the switch. Passed UL, no more. $40 power drill or blender, 4 cent switch.

Unplugging from a power strip, then unplugging the power strip does sound a bit OCD however.
 
D'oh! Tampa, not Tamp. Got past the spell checker....
 
I wouldn't worry too much about the plugs going bad. Do you leave your vacuum cleaner plugged in all the time? How about your hair drier? Your clothes iron? How often have you had to replace the plugs?
 
We plug our vacuum, waffle iron, battery charger(NiMh), pop corn popper and occasionally (depending on counter traffic), the toaster into one specific receptacle. The other side has a power-strip permanently plugged in. This is easily THE most used duplex receptacle in our house with the added occasional side yank offered by the vacuuming process.

I can say it lasts about 6 years before I get nervous about the growing looseness and replace it.

Keith Cress
Flamin Systems, Inc.-
 
Makes me think. A duplex outlet replaced with a single outlet and an "isolation switch" for people that want that extra security.
Had my cordless plugged in downstairs and I went down in the evening and found the charger in meltdown mode.
That is one device I would always isolate.
I personaly dont trust all the transformers feding the electronics such as printers, kids games, speakers, etc.
I would isolate those at night if it were easy.
I wonder if that isolation switch exists. Most ideas I have if any good already exist if it is a good idea.
Great stocking stuffers.
 
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