In one corner of my bedroom, I’ve got a standard wall electrical outlet with receptacles for two three-pronged plugs. For the last few months, ever since I’ve lived in this apartment, a standing lamp has been plugged into the bottom receptacle, and a power strip has been plugged into the top receptacle. Plugged into the power strip, in turn, are my stereo, TV, and DVD player. Today I noticed that neither my TV nor my stereo (nor, when I checked it, my DVD player) would turn on. Turns out that the power strip itself wasn’t on either. The lamp, however, worked just fine. After some experimenting, I discovered the following:
The lamp works when plugged into either the top or bottom receptacle.
The power strip doesn’t work in either receptacle, but works fine when plugged in elsewhere in the apartment. I bought a brand spanking new power strip…same deal.
The stereo doesn’t work when plugged directly into either receptacle. Presumably the same is true of the TV and DVD player, but their cords don’t stretch that far.
My cell phone charger doesn’t work in either receptacle, but works fine when plugged in elsewhere.
So it appears that, with the exception of the lamp, the outlet no longer works. (It was working just fine on Wednesday.) I guess my questions are, first, whether there’s anything I can do to fix it (or do I just call my landlord?) and, second, why it might be that the lamp works in the outlets when nothing else does.
Call your landlord and have him replace the outlet. It sounds like there is some problem with the internal contacts which connect with the lamp, but not with the other devices you tried. In the meantime, just for safety’s sake, I wouldn’t use the outlet.
Thanks. But when you say “there is some problem with the internal contacts which connect with the lamp, but not with the other devices you tried,” don’t you mean it the other way around?
No, what he means is that there is a problem with the internal contacts of the outlet. The result of this problem is that they still manage to make contact with the lamp, but not the other devices. A slightly odd (but not unheard of) problem, but a simple cheapo outlet and about 5 minutes of work should have it resolved.
Sounds like the guys have it covered.
I would say that the prongs in the outlet itself are stretched out and won’t connect properly with anything but the lamp. Are the prongs on the lamp plug wider or otherwise much different than the prongs on the plugs of everything else you’ve plugged into that outlet?
It is odd that something would just stop working like that if the outlet is worn out. Especially both top and bottom at the same time.
Usually you’ll get some electrical connection if you wiggle the plug in the outlet too.
Let us know what you find when/if it gets fixed.
If you choose to do it yourself, MAKE SURE THE POWER IS TURNED OFF!!
And be sure to replace all wires exactly as they are on the current outlet. If you have any questions ask.
I’m not sure what happens with electronics if you reverse the polarity, but I’d imagine there could be some things that won’t work if the polarity of the wiring is reversed to the plug. Therefore, when you plug in a polarized plug into the outlet, it’s always wrong. A lamp wouldn’t matter, but I"m not sure about the transformer on a cell phone charger or a stereo. There might be some kind of protection built into the strip to keep the polarity from being reversed.
That won’t bother the stand-alone electronics any, but it can cause problems in stuff that’s connected to other stuff that’s plugged into other outlets or fed with external wiring, such as cable TV.
At best, you can get what are called ground loops when the frames of different items are at different potentials relative to ground. The most common symptom is hum in the sound, or ripple in a TV picture. Some gear has an intentional connection from its frame to what should be the neutral/grounded wire - an old stereo amp of mine was like that - if the outlet was mis-wired, you could get a tingle off the thing.
At worst, that little tingle could be a life-threatening electrocution, or equipment could be damaged when it’s connected - if your TV had 120 volts on its chassis, and you hook it to the grounded cable TV line, you could blow fuses in the TV, or damage the cable TV wiring.
Stand-alone things like clock-radios or phone chargers won’t know or care how their power is phased as they have just the two wires.
As for the mystery of what works or doesn’t work in which outlet, my guess is that the lamp has the somewhat older style plug where the blades are flexible enough that they can be easily bent outward slightly with your fingers. The phone charger, TV and power strip probably have the newer solid blades that can’t be bent much, if at all, without help from a pair of pliers.
My best guess is that the neutral contacts in the receptacle are very stretched. Here’s my reasoning:
All lamps use a polarized plug, which means the neutral prong on the plug is wide. All power strips use a 3-prong (i.e. grounded) plug, and the neutral prong on the plug is of normal width. The neutral contacts in the receptacle, being very stretched, are able to make contact with the (wider) neutral prong on the lamp plug, but are unable to make contact with the (normal width) neutral prong on the power strip.
Anyway, it’s my best guess. What’s odd is that is that, if my theory is correct, the problem must be occurring in both the top and bottom receptacle. :dubious:
If this is the problem, you obviously need to replace the outlet.
Another theory is that there’s only a hot connection at the outlet (no neutral), and the lamp’s neutral is somehow getting grounded through some external connection, which makes the lamp light. Not likely, but not impossible either.
But since lamps don’t usually have a ground prong, that would mean…
a)there’s a short to a metal part on the neutral side inside the lamp
AND
b)that metal part is being grounded
That would be bad, you’d get a shock if you picked it up. My vote is still for a bad outlet.
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but I"m not sure about the transformer on a cell phone charger or a stereo. *
Transformers don’t care which way they’re plugged in.
Could it be that the wall outlet is controlled by a wall switch and that the switch could be defective? It isn’t uncommon to have one half of a wall outlet controlled by a switch.
What’s odd is that is that, if my theory is correct, the problem must be occurring in both the top and bottom receptacle. :dubious: