2

We accidentally ran our microwave and an electric tea kettle on the same outlet at the same time. Suddenly neither would turn on. I brought out my volt meter and it reads a curious 13 volts vs the nearest outlet that reports 122 volts.

I checked the breakers and reset each one and even took off the outlet cover and hooked the volt meter up to the wires and it still reports 13 volts.

The outlet appears to have 3 wires, I'm guessing the neutral, the ground and the hot wire.

I haven't removed the outlet and tested the wires without the outlet in the circuit... But does this sound like a busted outlet?

I can't seem to find any other outlets reporting low voltage so I'm guessing there's nothing wrong with the breaker or the wires.

  • If it's in a kitchen, look for a tripped GFCI outlet somewhere nearby. – isherwood Jan 14 '16 at 3:38
  • I have one about 3 feet away, I hit the test and reset, and still no dice – Matthew Levine Jan 14 '16 at 3:42
  • 3
    a coworker of mine thinks it could be a melted line or neutral wire somewhere. Considering it's getting 13v even on going hot to ground, maybe that means the hot wire melted somewhere (?) – Matthew Levine Jan 14 '16 at 7:08
  • 4
    I would definitely call an electrician in your case. In the meantime, consider disconnecting that particular circuit at your breaker panel. This smells a bit funny to me... – user Jan 14 '16 at 13:04
  • 1
    if the outlet was wired using the stabs (wires pushed in) not screwed in the connection of the hot side probably melted or you would have 120 from hot to the ground. Turn the breaker off if stabs are used pull the wires out and connect to the screw terminals or replace the outlet. If not at that outlet go to the next one prior to that and do the same check. – Ed Beal Jan 14 '16 at 14:35
1

I suspect you may have something called a multi-wire branch circuit, which uses one set of three wires (rather than two pairs of wires) to handle as much load as two separate circuits. Current electrical codes require that multi-wire branch circuits must be powered by a pair of breakers that are interlocked so that whenever either one is turned off or tripped the other will likewise be disconnected, but some installations lack that interlock. Yours may be one of them.

If a circuit is run as two wires from the panel to the load, then when the breaker trips everything in the circuit will be de-energized. Likewise if a multi-wire branch circuit is run as three wires and both breakers are tripped or switched off, everything will be de-energized. Unfortunately, if only one breaker trips, devices on the side of the circuit controlled by disconnected breaker may receive a generally-small amount of current through devices connected to the live breaker. While such currents would generally not be large enough to cause a fire unless they were sufficient to trip the breaker on the other side, they could still be lethal to someone touching the "disconnected" circuit. Worse, a variety of factors may cause the amount of available voltage and current on the "disconnected" circuit to change unexpectedly, so even if a voltage tester shows that a circuit is "dead" that doesn't mean it won't seemingly-spontaneously become lethally energized as soon as the tester is put away.

Multi-wire branch circuits are cheaper to install than individually-wired circuits, and are perfectly safe when the breakers controlling them are properly interlocked, but can be dangerous when such interlocks are not installed.

| improve this answer | |
  • Interesting, first I've heard of it, but then again, I'm pretty new to the world of electrical circuits. Given that, are you saying that it's possible there's another breaker that might need to be reset? I plan on trying to reset all of my breakers again to make sure I did it properly and with enough force. But if you have any other ideas on how to resolve it (even it if it's "call a pro") that would be excellent – Matthew Levine Jan 14 '16 at 22:15
  • 1
    @MatthewLevine: Circuit breakers are designed with a mechanism which is cocked by moving the handle to "off" and released when an overload occurs, so a breaker can trip even if the handle is held in the "on" position; the handle will spring to the "tripped" position if it can, but the circuit will disconnect regardless. If you haven't flipped all connected pairs of breakers off and back on, it may be that one of the breakers has an insufficiently-strong "tripped" spring to switch off the other breaker, so the untripped breaker holds the tripped on in what appears to be the "on" position. – supercat Jan 14 '16 at 22:52
  • Luckily for me this turned out to be the problem. Either multiple breakers were tripped (but not showing it) or I didn't proper flip the breakers when I tried it the first time. I went through and carefully flipped each breaker off and on and that did the trick. Like you said, I probably have one of these dual breaker circuits setup (which would explain getting 13v instead of 0) or I simply didn't flip it correctly the first time – Matthew Levine Jan 15 '16 at 4:30
  • @MatthewLevine: I'd suggest overloading the outlet again to trip a breaker and find out which breaker tripped, and whether the failure to trip the mate was a one-time thing or represents consistent behavior. If the latter, one or both breakers should be replaced to ensure that a trip on either will disconnect the other, since the scenario where one trips and the other remains live can be dangerous. – supercat Jan 15 '16 at 15:30
1

Since you have a meter, flip the breaker off for this circuit and remove the receptacle. Keep the wires separated and safe and then flip the breaker back on. Check the voltage between the hot and neutral. If it's 120V, then replace the receptacle. If it's still 13V, then the problem is upstream of this between the walls or at another receptacle along the line.

If this is the issue, you would have to check out each receptacle along the line until it returns to 120V from hot to neutral, this would mean the problem is between that receptacle and the last measured. Since you said that the nearest receptacle is at 120V, I'm assuming that it's on the same circuit and the next wired in sequence? If anything, your problem is between this receptacle and your problem receptacle; in wiring or in devices.

| improve this answer | |
  • That's what I'm leaning towards. I really hope it's not a melted wire because I have no clue how one would fix that if it's in the middle of the wall. I bought this house a little over a year ago so I'm not terribly familiar with how the kitchen is wired. Any idea on how to check which receptacle is connected to this one in the sequence? – Matthew Levine Jan 14 '16 at 17:37
  • 1
    @MatthewLevine Flip the breaker for that circuit and then go around testing each outlet nearby to see which don't have power anymore. You can do this with a non-contact voltage tester, your meter between hot and neutral, or just with say a nightlight. Find our what all has been switched off and that'll be your circuit. Most likely the next one in sequence would be the one physically closest, but you'll again have to revert back to my answer of testing each outlet down the line. – TFK Jan 14 '16 at 18:17
  • 1
    @MatthewLevine For fixing the wire, your best bet would be to find both ends of the wire (at your current receptacle and the one upstream of it) and disconnect them from their outlets. Next, tape, twist, and wrap one end of the old wire with an end of your new wire. Tug on both ends to ensure that it's held together tightly. Last, go to the other end of the old wire (the one that's not tied to the new wire) and simply pull it until the new wire peaks through the box. Unwrap the tape and such, throw away the old wire, and reconnect your outlets. Again, it's only if you need to go this route. – TFK Jan 14 '16 at 18:29

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.