How do I debug when a circuit breaker keeps tripping?
I turn off the lights it controls. I unplug all the outlets.
It still trips.
How do you debug these things?
I'd start by disconnecting the load at the breaker and then see if the breaker still trips.
If the breaker is OK, then I'd start removing and disconnecting outlets and switches on the affected circuit until I found the problem.
You didn't recently nail/screw/install something on a wall, did you?
To "disconnect the load at the breaker", do you mean that I should just physically *remove* the breaker, and see if it trips on its own, in my hands?
To "disconnect outlets and switches", do you mean to pull them out of the wall, one by one, disconnecting the hot wire only? (Would that be enough?)
No, I didn't recently install anything (that I know of).
UMM... AHHH, UMMMM, AHHHHH ..... WOW ............ AHHHHH OK.... I think they meant you should remove the LOAD from your telephone book, (such as a stack of other books on top of it), then look up electricians and call one. The only only thing that might trip in your hands, is your index finger, if it trips while your fingers do the walking thru the yellow pages.
Yep, that's what they meant!
They just meant you should disconnect (unplug) everything until the electrician arrives.
That's good!
In the situation you describe, I suspect that the easiest way to debug is to replace the breaker. I'm told that sometimes they just crap out on their own after years of use. Your time is worth something and the breaker isn't that expensive. Buy a replacement and swap it out and see what happens.
Does it actually *reset* and then trip? When they go bad they don't reset or *catch*...showing you its needs replacing. Have any of the outlets been worked-on to be suspect?
Or switch wires at the breaker between that breaker and an adjacent one as a test.
I had a GFCI breaker fail when it was only about 5 years old. The replacement is 31 years old and doing fine. Regular breakers are a quite a bit cheaper than GFCI
If he's going to do this he should turn off all the power to the breaker box by flipping the main breaker at the top, and use a flashlight to see. Or at the verrry least he should keep one hand in his pocket, literally, so he can't touch things with two hands and get killed, literally.
First turn off the breaker in question.
Then when the breaker is off, unscrew the screw that holds the wire at the end of the breaker that's not in the middle of the box. Probably don't have to unscrew it all the way. You don't want the screw dropping into the box, and you don't want to be reflexively showing your hand in the box when you see the screw about to fall. If it does fall, just let it.
Grab the wire on that screw by its insulation and push, pull etc. it off the screw.
Then lift the end of the breaker away from the center of the box up and pull/rock the breaker out of the clip it's in at the center. It should come out quickly.
Reverse to install. Except that it might be easier to hook the wire on the screw BEFORE putting the breaker in at all. Maybe you can use two hands for this part only.
You definitely DON"T want to remove the screw, if it even comes out, because it will be hard to get it back in, but it probably comes out enough that it's easy to hook the wire back on it.
Use the same size breaker, 15A, 20A, whatever was there. You can't safely increase the size.
>On Wednesday, January 20, 2016 at 8:12:36 AM UTC-5, Micky wrote: If he's going to do this he should turn off all the power to the
The OP doesn't know anything about a panel and you've left out an important step that will confuse him.
After you've turned off the main breaker, you can't see the screws or the wires. There is a safety shield in place. That must be removed, carefully.
And remember, with the main breaker turned off, there is no power to the buss bars, BUT there still is lethal current available up top.
Removing that steel cover is what makes me the most nervous because as you say, there is still the incoming live feeds at the top. Watching that Holmes show from Canada, I noticed that their panels had a separate cover for that area, so that if you turned off the main and remove the other cover for the breakers, no chance of hitting anything live. I wonder, is that just a Canadian thing or do some or all new panels here have that too? Required by Canadian code thing?
Take the wire off the breaker. See if it will reset. If not, get a new breaker. If it resets, take a meter and see how many ohms it shows to the neutral wire for that breaker. Then see how many ohms to ground. If any ohms to ground you have a major problem to look at, should not be any, or way up in the mega ohms atleast. If any below several thousand (really should be up in the megaohms same as to ground) on the neutral to the wire you took off the breaker then something is still connected or there is a short in the wiring.
If very high ohms to neutral and ground, then swap that wire with another breaker wire of the same rating and see if the other breaker trips. If not, replace the breaker that is tripping.
This is assuming you do not have a ground fault breaker. If so it could be water on an outside outlet that may not show up on the ohm meter.
If you had a meter that has a clamp on ampmeter, you could look at it and see if it goes way up when you turn the breaker on, but many do not have a meter like that.
If you don't have a multimeter, get one as they are less than $ 20 for one that is good enough to use around the house.
That's what the flashlight is for. :-)
Hmmm. I haven't seen it for years, but in mine I didn't think the power was very available. I'd have to stick my fingers more than 2" down between the main breaker and the top of the box and even then, the cable that was showing was insulated. Maybe if I bent my finger I could get to part where the insulation was off. Anyhow, OP, don't do that.
"It /was/ tripped" suggests you discovered it tripped; as opposed to it tripping while you were DOING SOMETHING.
Does "immediately" mean "within a few seconds"? Or, does it mean "it never actually SETS"? You are REsetting it before attempting to SET it (i.e., turn it fully OFF, then ON)?
Are you positive that there are no other hidden loads? Doorbell? AC powered smoke detector? Wall clock? etc.
How many lights does it control? How many outlets? Are there other outlets or lights in those rooms that are NOT on the same circuit?
I asume you want to know how *you* should debug this, not I?
What level of experience with electricity do you have? And, your personal "Comfort Factor"? How deep is your wallet? I.e., are you asking out of curiosity? Or, out of *need* (ABSOLUTELY can't afford to hire someone)?
I am in Canada, my breaker panel was new just after we bought this house in 97, installed by an electrician, and passed inspection, it does not have a separate cover for where the live wires enter it. So I can say that was note code then, though it may be now.
One other thing that should not need to be said. When you flip it back on, did you turn it all the way to OFF before turning it back on ?
This needs to be done to reset most breakers.
I've removed panels, but rarely. Big aluminum wires. Really big. Bare wire.
Thicker than a garden hose (110Amp service). Makes your breathing go up a notch just looking at them.
Even so, I've replaced a breaker (220VAC house panel for a built-in AC which had it's own separate breaker at the AC unit)
- but only once.
So, advice is handy. I will read it all.
Nice idea! Thanks!
That saves me the 30-mile round trip to the hardware store. (Am in the boonies.)
Haven't anyone in the house to see if the lights go on momentarily, and I can snap a video if you like (will need to find a place to upload it).
When I reset it, it doesn't stay. It's as if a spring-like force is forcing it to the trip point.
There are three positions, but it won't stay in the off position, and it will easily stay in the trip midway position, but it won't stay in the on position.
I tried it a dozen or more times, and all goes right to the trip position. Once I saw a spark, not big, but blue. Stopped at that point.
Clearly a short somewhere.
Another great debugging idea. Will try.
If it will not stay in the OFF position that indicates something is wrong with that breaker. A spark or flash does not mean much. If there is a bad overload, repeated resetting of the breaker could cause it to go bad.
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