How did half an electric outlet die?

July 18, 2005 9:18 PM

Today the top half of a regular wall outlet stopped working. No pulling or pushing of plugs was involved, and the bottom half still delivers electricity without problems (AFAIK). As the bottom half is still powered, it doesn't appear to be a switch or fuse issue (None are tripped). How would this happen, and how difficult a repair is this likely to be? Is it likely a problem simply with the outlet itself, or the wiring in the wall?
posted by birdsquared to Home & Garden (11 answers total)

Most outlets have a tab on them that can be broken off, usually so that one half can be switched and the other unswitched. I'd say look again for a wall switch, that's where my money is. In my neck of the woods, this isn't done as often in favor of switching the whole outlet, but half the outlet can be and definitely is done.
posted by RikiTikiTavi at 9:32 PM on July 18, 2005

What did you have plugged into it?

Is it in the Kitchen? Kitchen outlets are often split, which means that each outlet of the receptacle is on a separate fuse/breaker. RikiTikiTavi's explanation is equally valid, but would probably be in a living room.
posted by Chuckles at 9:36 PM on July 18, 2005

If this is a regular outlet, then most likely it went bad. It happens every once in a while.. Just buy a new one from the hardware store for about $1 and replace it. When you take the old one out, make sure the circuit breaker is off, and inspect it to see if there are any scorch marks from arcing.. that might explain it.
posted by rajbot at 9:48 PM on July 18, 2005

Going on from what RikiTikiTavi said, it's possible that there's more than one circuit on the outlet. Be ultra-paranoid about replacing this outlet. Turn off your whole house power before mucking about in there.
posted by 5MeoCMP at 9:51 PM on July 18, 2005

It is in the kitchen. The toaster was plugged in to the top, the microwave into the bottom. It's most likely not split, since both top and bottom worked fine until today, with no switches involved.

rajbot - thank you. I didn't think that an outlet could "go bad" on only half of it. I'll try to replace it and hope that solves the issue. I'll certainly be taking care with the replacement process.
posted by birdsquared at 10:30 PM on July 18, 2005

If you open it up, and there are separate wires running to the top and bottom half of the outlet, you're dealing with the two-circuits thing and will need to make sure the outlets are not bridged before you reconnect it. (As Riki points out, there's a tab you break off.)
posted by kindall at 11:08 PM on July 18, 2005

(It's also possible that if it has wires going into both the top and the bottom that the outlet is in the middle of a daisy-chain of outlets --- in which case everything "downstream" of the bad outlet would also have gone at the same time.)
posted by hattifattener at 11:28 PM on July 18, 2005

Also, for outlets in the kitchen and bathroom, and especially if it's near the sink or dishwasher, you should use a spendy GFI outlet.
posted by trevyn at 12:00 AM on July 19, 2005

GFI outlets are not that expensive, and per National Electric Code must be used as replacements if installed within 6 feet of the sink.
posted by scottymac at 12:23 PM on July 19, 2005

How is the toaster? Can you see carbonization on the toaster's plug?

Also, you can get non-contact voltage detectors at Radio Shack and probably at hardware stores. For under $10 it is a great tool to have around. I find it very reassuring to confirm that I got the correct breaker.

Also, you should be able to hold it near the top and bottom plugs... If it is just a mechanical problem you should still detect voltage on the top one, even though it doesn't work.

A ground fault outlet would be a great idea. It would be a good idea to find all the outlets on the breaker in question however. If you put the GFI on the first plug in the chain you will protect them all.
posted by Chuckles at 5:21 PM on July 19, 2005

Well, I replaced the outlet today. As it turns out, it WAS split, which I still don't understand, because I can't find a single switch or fuse or breaker that would explain the loss of electricity to it. There is/was no blackening of the wires nor the toaster plug (the toaster works fine). I had to go back to the hardware store to get an aluminum wire outlet, since it turns out the wiring on that wall is AL. I decided against the extra $15 for a GFI outlet, since it is on the other side of the kitchen (though probably within 6 feet of the sink) - but I'm in Canada, so I don't think the (U.S.?) National Electric Code applies.
I attached the black wire to the outlet, and left the tab on, and simply left the red wire (which had been attached to the non-functioning top half) unconnected. I attached the neutral and ground wires, and everything appears to work fine.

There shouldn't be any problem with the unattached red wire, right? It's currently (pun intended) not connected to anything and is behind the receptacle, so there shouldn't be any movement of the wire at all, nor the opportunity for something to connect to it accidentally.

I've checked every single other outlet in the apartment, and they all work, so I don't think the red wire was/is a pass through.

Thanks for all the replies.
posted by birdsquared at 8:06 PM on July 23, 2005