GFCI Outlet Question

[mooseshoes]

All:

I have a house that is 2 years old and recently after testing my breaker box switches for an outlet match I lost power to a few outlets and switches in my home, including an external light, an outlet in the garage (used for the sprinkler system) and one inside. I read where sometimes the GFCI outlets get tripped so I paraded around my home and made sure every GFCI switch was set properly and that all breaker switches were on. Still no power.

The likely culprit is a GFCI switch at the workbench in the garage. The kicker, however, is that that outlet is working fine. It is controlled by the breaker switch labeled "GFCI Garage."

Therefore, I have no way of figuring out why those outlets aren't functioning. I've tried resetting all the breaker switches too...

Frustrating...

Any suggestions?

Thanks in advance,

Steve

----- Look for decreasing temperatures this winter with the likelihood of warmer weather in the spring.

[Jeff Wisnia]

Without any further details, I'd take a WAG that one of the breakers in the panel decided to get "sticky" and didn't close again after you flipped it open.

Since it sounds like you're among the majority of homeowners whose breaker boxes aren't fully labeled (Only us anal engineer types do that anyway.), then.....

The simplest way to see if my guess is correct is to remove the front cover of the breaker box and check for voltage on the output terminal of each breaker, relative to the "neutral bar" to see if there's one that's "dead", even though the breake is flipped "on."

You can use a test lamp or a voltmeter to test for that, IF you know what you're doing around exposed line voltage circuits. IF YOU DON'T, then puhleeze get someone who does to help you.

If you find such a "dead" breaker, try flipping it on and off again a few times. Breaker handles can often look like they are in the correct position to be "on", but aren't really.

Good luck, let us hear what you discovered.

Happy Holidays,

Jeff

-- Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"If you can keep smiling when things go wrong, you've thought of someone to place the blame on."

[mooseshoes]

the tests inside the breaker box, but since I haven't done so before I want to make sure I understand your terminology properly.

I will remove the cover of the breaker box and leave the main AC switched ON. I will then identify the "neutral bar" which I"m assuming is labeled accordingly but if not probably be a bus-type block located near the top of the box and receiving white wires. I will then look for the "output terminal for each breaker" which sounds like would be a connection located near each of the switches. I will measure voltage across these two points with a voltmeter.

Please let me know if the process is accurate and I will proceed with great care.

Thanks!

Steve

[Jeff Wisnia]

Probably not labled as such, but pretty easy to spot. It'll look much as you described and have a whole bunch of white wires connected to it.

You got it just right. The breakers' output terminals are the ones the black wires connect to. Most often only one wire per breaker, but some local codes allow the use of breakers which can accept two black wires per breaker.

If you happen to have any GFI breakers in the box, they'll have two output terminals, one each for the black and white wires on the circuit they're protecting.

Good luck,

Jeff

[Chris Lewis]

According to mooseshoes :

That's basically it. Once you see the insides of the panel, it'll be obvious. Each breaker will have a terminating screw and a wire attached to it. The buss bar will usually be an aluminum bar with a lot of setscrews in it, plus white wires, barewires, or both. Go with the bus bar that's got white wires on it (it generally doesn't matter that much actually, but just to ensure consistency).

You measure voltages between the selected bus bar and the terminating screws on the breaker.

HOWEVER, I'm going to suggest that you turn off the main _first_. Remove the cover of the breaker box, and look around inside, familiarizing yourself with it. Then, if your voltmeter has an insulated alligator clip on one of the leads, attach that to the neutral bus bar. Or even screw it into the neutral bar as if it was another neutral wire.

[That last bit simply means you have one less hand to worry about fumbling around in the panel.]

Then turn the main back on, make sure the VM is set properly, and use the other VM lead on the terminating screw for each breaker. Keep the other hand behind your back.

Caution: high impedance VMs _may_ give misleading results on 120V. All the breakers that are on should give exactly the same value. Don't worry if it's not exactly 120V. Do worry if you see voltages more than a few volts away from the common value. Ie: don't expect a dead breaker to read exactly zero volts. A high impedance meter can read as high as 100V on a disconnected circuit!

[David Babcock]

Plug a radio into the dead plug, turn it up loud. Go to the panel and switch the suspected breakers a couple times. If nothing happens........now remove the cover and check the voltage. Maybe a breaker..........broke. Buy a new one.

[TimS]

Good response! I can only add...

Keep that 1 hand behind your back and think about your weight/balance as you work. If some thing happens you want to fall away from the box. I try to keep my weight on a bent back leg (to fall away).

When you first take off the cover (with the main[s] off, could be up to 6 switches) look around for possible cover to conductors contacts point at re-assembly. White wires, low risk, black, red wires, high risk. When the panel goes back will any conductors be 'pinchable'?