The better reason to unplug your appliances is that many drain electricity even when turned off, amounting to about 5% of monthly usage according to some:
http://findarticles.com/p/articles/mi_m1590/is_n8_v54/ai_20184544/pg_1
Why is that? (I mean, “Why are Air Force people like that?” not “Why did it take some …?”)
Joe
This morning I took another look at the receptacle I mentioned above and it is, in fact, unpolarized. My apologies for the bum information.
CookingWithGas: I may have confused you. Polarized does mean that the short slot is connected to a hot wire, and the long slot is connected to a neutral wire. Polarized outlets existed before grounded outlets, and have nothing to do with ground wires. [I mentioned wire coloring above solely because the modern convention is for the white wire to be the neutral wire, whereas in old k&t wiring the white wire was the *hot* wire - a potentially dangerous situation for some do-it-yourselfer who isn’t aware of this fact.]
In modern systems the neutral side is grounded at the breaker box (whether there are ground wires or not), which is why you could fix your ground-loop problem by simply reversing the plug on your amp.
Related question: why on earth don’t American standard wall outlets have on/off switches?
Some do, typically for living room outlets intended for one or more table lamps, since traditional living rooms have no ceiling lights.
But since almost every electrical appliance has its own switch already, putting another one in series would just increase the uncertainty of whether it was on or off.
Well, sure, but you’d think the additional safety benefit would more than outweigh any possible inconvenience. Besides, if the outlet is used for a lamp or somesuch you can always leave the switch on.
(UK 3-pin sockets always have switches, like this)
What is the safety benefit?
You don’t have to stick plugs into live sockets, for one.
I’ve been shocked perhaps a dozen times trying to stick two-prong plugs into outlets that were behind furniture, or whatever.
Two, it’s an awful lot more difficult for Baby Jane to fry herself by sticking forks in outlets.
Three, you don’t have to run to the household mains/breaker box to shut off power to the outlet, which can save seconds or even minutes.
Can’t you just, you know, handle the plug by the insulated part, not the prongs?
In the past there wouldn’t have been a breaker, just a fuse box, either with cartridge fuses or rewireable plug-in fuses (which would occasionally blow for no particular reason). Some folks would ‘rewire’ this with a nail or a piece of wire if they hadn’t got any fuse wire left since the last time it blew.
I had a friend forty years ago whose parents religiously pulled the plug out of the TV every night. It’s not really necessary any more.
I always unplug my toaster after I saw this on a board I read - “Black Friday” Fire Guts Kitchen
I am finishing a room and it seems that electric codes here in NC have changed recently. The most recent change is breakers now should be arc fault which costs 5x the normal breakers. Also the room must have one outlet that is controlled by a switch. The outlets also must be the type that are protected so you can’t easily stick something in them.
I first noticed the polarized plugs in the first week of July 1980. I had sub-let an apartment from a friend while he was on vacation, and tried to plug a lamp in the wall and went nuts trying to figure out why it wouldn’t go in. I finally saw what the plug looked like, and very nearly started to attack the extra metal with a file.
I was out of the US from Sept 77 to May 80, so I guess it happened somewhere during then.
EVERY room???
Are you sure that’s not just the rule for rooms that don’t have a switched light fixture on the ceiling (as has been the rule for many decades)?
To be honest, if I ever rewired my house, I’d probably incorporate something like this. I’d have a triple switch at my bedroom door, one of which would control the fan, the second would control the light on the fan, and the third would control the switch behind my bed that my lamps are plugged into. I could do something similar in almost every room in the house.
I don’t know if that is the rule for every room, I will ask him on Monday when he comes back to work more on the room. I can add that this room does have an overhead light controlled by a switch.
AFCIs went into the NEC about ten years ago. People complain about the cost but they are fairly effective at preventing a lot of the more common types of electrical fires.
The NEC requires a “lighting outlet” to be controlled by a switch in every habitable room. A light fixture is a “lighting outlet” by NEC definitions. I just looked in the 2008 NEC (the latest version I have handy) and that hasn’t changed. Unless the rules changed this year, your overhead light should satisfy the NEC. Your particular location may have its own rules though.
Am I was the only one who was momentarily shocked to see an apparently new post by the late Q.E.D.? It brought a whole new meaning to the term “zombie thread.”
Nope. It threw me for a minute too.
**Did electrical appliances and items regularly explode in the past? ** Very rarely do things explode in the future.
I am not an electrical engineer.
I do work in an emergency call centre for an electricity distribution company in the UK, which is to say that my company owns the physical distribution network for electricity and I take calls for any problems relating to this, usually “power cuts”.
There is a thing called a “neutral fault” where the neutral to a property or properties is lost and under this condition the voltage which is normally around 240v can vary significantly up or down. If you are lucky you will see very low voltage in your house. If unlucky very high, and appliances will burn out or even catch fire. Televisions have been described by customers as “exploding”.
I have been with the company around 8 years and have seen very few of these faults, thankfully. Noone’s house has caught fire and noone has been hurt.
Don’t ask me technical questions, I just log the calls and apologise to people.