Electrical Circuit out - tracking it down

[GaryInCO]

!!! I pulled the office outlet that I thought might be the most-upstream, and that one had backstabbed neutrals. (But not hots?? What was I thinking!?) I had already tripped the breaker for the office outlets so I went to pull the backstabs and re-do them, when I realized... WTF!? This outlet is live!?!

It's on the other side of the wall from the entryway, which is on another circuit. And they must have pulled a line THROUGH the wall from the entryway into the closet, I think just for that ONE outlet. Isn't that against code!? I thought the outlet was dead along with the rest of the outlets in the room. Damn lucky I tested it first.

But ... there are lines going in AND out of that outlet. It's not just a pigtail hanging off the entryway circuit. Maybe it goes back across the wall into the entryway / living room / etc. Or maybe not. I think it's time to call it a night and look at this more carefully in the morning...

 

[Sunset]

Since we're talking about outlets, I found this very helpful short video.
Did anyone else know of this trick or hack as we call it these days.
............

I never knew about the wire stripper, pretty handy.

 

[ERD50]

.... when I realized... WTF!? This outlet is live!?!

It's on the other side of the wall from the entryway, which is on another circuit. And they must have pulled a line THROUGH the wall from the entryway into the closet, I think just for that ONE outlet. Isn't that against code!? I thought the outlet was dead along with the rest of the outlets in the room. Damn lucky I tested it first.
...

Exactly why you test them. You can't really know which outlets are on a branch by physical location, sometimes the "as the crow flies" distance, or convenience during initial install (or remodel) means an outlet is on a branch that you might not expect.

It isn't luck - it is what you are supposed to do (check for power) - every single time. Don't assume anything.

I really don't think there's any code against a branch being split across rooms, or run through a wall - I think that's done all the time. It can be seen as an advantage to split circuits, it might be less likely to overload a circuit that is split across rooms? Or did you mean something else by that?

I never knew about the wire stripper, pretty handy.

I did not know that either!

-ERD50

 

[mountainsoft]

I really don't think there's any code against a branch being split across rooms, or run through a wall - I think that's done all the time.

When I wired our house back in 2003, there was at least one situation when a circuit was required to be split across multiple rooms. Hardwired smoke alarms should all be interconnected so if an alarm goes off in one room they go off in all rooms. It was also recommended that the smoke alarms be placed on a lighting circuit, such as one of the bedrooms. The thinking is you would notice if the bedroom lights weren't working, but you may not notice if a dedicated circuit for the alarms was tripped.

 

[ERD50]

When I wired our house back in 2003, there was at least one situation when a circuit was required to be split across multiple rooms. Hardwired smoke alarms should all be interconnected so if an alarm goes off in one room they go off in all rooms. It was also recommended that the smoke alarms be placed on a lighting circuit, such as one of the bedrooms. The thinking is you would notice if the bedroom lights weren't working, but you may not notice if a dedicated circuit for the alarms was tripped.

Agreed. And this is why I think it's a bot off the mark that the recommendation (a quick search says it is not code required) has been to have the kitchen fridge on a separate circuit.

If you have a fridge w/o all the bells/whistles and display panel up front, you may not notice the breaker being tripped. But if you turn the kitchen lights on and get nothing, that will get your attention.

Lights don't take that much power, it shouldn't be a problem for the fridge load. If you are worried, put in a 20A/12GA for that branch.

-ERD50

 

[GaryInCO]

I was just surprised that there were outlets on multiple circuits in the same room. I thought they always put one room's outlets on the same circuit. Otherwise somebody might make the faulty assumption I did: the breaker is tripped, all those other outlets are dead, so obviously this one is too.... zzzap

 

[ERD50]

I was just surprised that there were outlets on multiple circuits in the same room. I thought they always put one room's outlets on the same circuit. Otherwise somebody might make the faulty assumption I did: the breaker is tripped, all those other outlets are dead, so obviously this one is too.... zzzap

As I said earlier, this is not something that should be assumed, ever.

Anyone making assumptions like this has no business doing anything with their home wiring, however simple it may seem.

This is like playing Russian Roulette. No one in their right mind would pick up a gun, assume it's unloaded, and then pull the trigger while pointing it at themselves or a loved one. An electric outlet can be lethal, you verify it is off before handling it as if it was off.

An experienced person can work safely on an intentionally live circuit, because they recognize the dangers and avoid the problems. But that is rarely needed, just turn off the breaker, verify, and re-verify, and make sure your tester is good, you can't rely on "I didn't get a reading" either. You have to see there is nothing (a positive action), which is different from not seeing anything (a passive action).

It's like driving. It's not safe to pull out on a road just because you don't see any cars coming. You have to see that there are no cars coming (IOW, verify any blind spots).

-ERD50

 

[GaryInCO]

The neutrals on that outlet last night seemed a bit flaky, so I un-backstabbed them last night. I thought it was on a separate breaker -- I think I checked it with the breaker finder? -- but this morning I noticed the other outlets were good! No open neutrals, power is fine. Ooookayyy...

Even stranger, the breaker finder this morning doesn't agree with what it said yesterday. The radon-fan breaker is tripped, but the outlets are still hot (probably why the outlet last night was hot?). Now the breaker finder says the outlets are on a different breaker!? And that breaker is marked "dining room," which probably refers to my office, even though it's marked "Library" on the original plans.

So I'm not sure why the breaker finder changed its story, but it appears I fixed the flaky neutral. Don't know why I backstabbed the neutrals on that outlet but that was apparently the cause of the problem. All seems OK now.

An experienced person can work safely on an intentionally live circuit, because they recognize the dangers and avoid the problems.

I'm relatively experienced... I have an EE degree and have a good understanding of electricity. But I was probably overly bold when I swapped out the switched & outlets. I did all 150+ of them with the power on. Stupid, I know, but I was careful.

 

[RobbieB]

I've worked on a hot circuit w/o any problems. You just have to be careful and it wasn't complicated (smoke detector) only one line. I always test with a meter before even removing the plate.

 

[GaryInCO]

I knew it was live, so I exercised appropriate caution. I did get "bit" a few times, but I was always careful to only have one hand "at risk." Didn't want current flowing from one hand to the other.

With 150+ outlets/switches in a large house, I saved myself miles of running back & forth between the work and the breaker. I was able to make the connections, test it immediately, move on.

 

[ERD50]

... I'm relatively experienced... I have an EE degree and have a good understanding of electricity. But I was probably overly bold when I swapped out the switched & outlets. I did all 150+ of them with the power on. Stupid, I know, but I was careful.

Electrical Engineer also. And while that helps, I find that electrical house wiring is a different beast that requires a different mindset. A lot of the building codes don't make sense on the surface when you just consider the house wiring as a schematic and a current and voltage loop.

But those codes make things as safe as possible with the given situation. I see some youtube videos and just shake my head - yes, the outlet is now powered, they got hot, neutral, and ground where they need to be, but they ignored several rules/codes and the result is that it is not as safe as it could be.

One recent example I saw, the good guy pointed out that with a metal box and three wires running to it, you ground the box first (the most direct ground connection), then you ground the receptacles. EE-wise, it's all the same on the surface. But the point was, if a hot wire came loose in the box, the priority is for that box to be grounded and pop a breaker. A poor ground at the metal box could mean a "hot" box that could kill someone that touched it.

There are a lot of subtle things that are easy to miss that still give you power, but could be unsafe under certain conditions.

-ERD50

 

[GaryInCO]

Yeah you can't think of house wiring as a simple schematic circuit. Yes, the circuit has to work. But the codes are there to make the circuit as safe as possible for the electrician and the people in the house.

 

[LJ Dem]

Half the house, in Canada

Late to the party here, glad you found the issues. Here in Toronto Canada 1/2 of my house went dark... just 1/2. Confusing! Our city electrical guys came (Toronto Hydro Electric) and asked if anyone had bumped the meter outside the house? Indeed possible: my neighbour had painters with ladders working around there. Turns out that bumping the meter can cause one of the two connections inside to go out of line... and cause 1/2 the house to go out. Our city electrical wires come into the house ABOVE ground and meet at the meter. He just pushed it back in, tightened it, and done. Managed to avoid an electrician bill (though would have to pay if the meter needed repair).
cheers and stay safe!