Need some electrical help

[Copper]

I'm having a small electrical problem and wanted to tap into the collective wisdom here. Please excuse the length, I'm just trying to give as much detail as possible. I just finished our basement about 3 months ago. We put in a wet bar area with cabinets. We recently bought a small microwave to make popcorn and installed it. Well, when we went to use it the first time, it ran for about 10 seconds and then all power on the circuit went out. I figured that since the outlets around the cabinets are on a GFCI circuit, that I just blew the GFCI. However, resetting the GFCI outlet did nothing. The breaker for the circuit also did not blow in the breaker box.

Here's how the wiring goes: The 14-2 power comes into a recessed light in the ceiling, which is on a switch. The power is spliced to the GFCI outlet on the wall, which has the rest of the outlets (including the one that had the microwave) on the load.

I can disconnect all the outlets and the lights still do not work. I have a feeling that I have a short in the light where the power comes in. But, if there's a short, why didn't the breaker in the breaker box trip? I hooked up a voltmeter to the wire going to the outlet on the wall. I read 120v between the hot and ground, but nothing between the hot and neutral when the light switch is on. I get about 10v when the light switch is off. So there is power running through the circuit. I have run many things on this circuit previously (compressor, vacuum, etc.) but maybe nothing that would pull as much of a load as a microwave.

Anybody have any clues? My next step is to cut a hole in the ceiling to gain access to the recessed light, but I wanted to see if anyone had any other suggestions before I do this.

Thanks in advance for your help.

[BobSch]

From the voltage reading, my first guess is a loose neutral or perhaps the ground and neutral wire are reversed.

[Uncle Cracker]

Too early in the morning to get my head around this, but a flag did go up when I read that you are reading 120V between hot and ground, but not between hot and neutral. Since the ground and the neutral are tied together back at the breaker box, this says to me that your neutral run has been interrupted, possibly with a bad or loose connection that just happened to open up when you used the microwave. If you have the wire (and it's as big as that in your walls), you could try running a temporary neutral from your outlet back to the breaker box's neutral bar. Everything should start working when you do that, if indeed an open neutral is your problem.

I'm sure there are other possible causes (I am always suspicious when there is a GFCI involved), but nothing is coming to my cloudy mind right now...

One other thing to remember when testing with a digital meter... Often, the meter does not put enough load in the circuit, and will give a false reading of voltage, when there is actually not enough of a circuit to provide any real power. Instead, use a "loaded" test device, such as a lamp or a radio. Then you will know if there really is any power available.

[LJR]

Sure sounds like a loose neutral wire.

Breaker didn't trip probably because the current going through the neutral wire opened up a loose connection before the current rating of the breaker was exceeded.

If I understand the scenario correctly it sounds as if you've connected a circuit serving outlets to a recessed ceiling light. At least some of the load on the outlets is a small microwave. To find the loose neutral you'll start at the panel itself to ensure it's properly landed there, but then I'll bet you end up at the recessed light and have to open the ceiling to get at that junction box. Do yourself a favor and go through the hassle and effort of taking the outlet circuit off the light and either run it back to the panel by itself or tie it in with an outlet circuit that can take the added load. That way you'll only fix it once.

[Copper]

Thanks guys. This confirmed my suspicions. I figured I'd check with all of you before calling an electrician. LOML wants me to do that before I open up the ceiling, but I don't feel the need to pay $100 or so for someone to come out and tell me something I already know. She still doesn't trust me after I wired, plumbed and framed our whole basement. This has been the only glitch so far...

In retrospect, I probably should have run the power into a more accessible junction box, but when the ceiling and walls are open it just seems easier to run it to the nearest spot and disregard future problems.

[Crash2510]

if this is a recessed can light there is no need to cut the ceiling. You could just drop the can out by removing the few 1/4" screws just inside the can. Turn your power off and try it, you could save yourself the cost of paying an electrician for a problem you have already looked into.