Hot Swap Breaker

[masraum]

Originally Posted by jyl

I found the main shutoff, it is on the external panel (?). I’ll post a pic later. So no hot swap needed.

The breaker I was replacing is not defective. There is a short somewhere in the circuit.

The circuit involves 1) the ceiling light which has two NMC cables (call them “A” and “B”) which I recall were connected and the old light pigtailed off the junction (I’m replacing with canless), 2) the light switch on the wall a few feet away, 3) an outlet on the wall directly below the light switch. That’s all the stuff that doesn’t work when the breaker is tripped.

When I connect the two NMC cables (black to black, etc) and the new light, the breaker trips. When I delete the light, the breaker trips. When I disconnect the “cold” cable B, and connect just the “hot” cable A to the light, the breaker does not trip, the light works, the outlet works, but the switch does nothing.

Hmm. I had assumed the outlet was wired to the switch (lots of weird stuff like that here), hot cable A came from the switch and powered this light and something else further down the line via cold cable B. But no.

Well, this is a mystery. I haven’t given it more than 5 minutes’ pondering, so not sure if it is a deep mystery or I’m just stupid.

Worst case, the light will just be on 24/7 until my electrician comes in a couple months to do a bunch of work and she can sort this out. We leave lights on at night anyway, to signal to would-be squatters that the building is not vacant.

Originally Posted by Dpmulvan

Neutral isn’t always necessarily cold in a switch loop.

That's what I was thinking. There are all sorts of ways that it could be working safely. There are things that should be done to ensure that someone coming along after the fact has a clue, for example, you could have a white wire that needs some black tape as a clue that it's actually hot. It's always a good idea to have one of the sensors that tells you when a wire is hot too. Try to figure out where the power is coming into the circuit (at the outlet, at the switch, at the overhead light fixture, and hook up one wire at a time in series until you complete the circuit.

[Zeke]

Don't wander off base. A repurposed neutral, generally the hot side of a switch leg should be taped black or at least marked black. Sometimes it's not done, but anything I can think off does not result in a dead short that is described here.

That having been said, the wiring sounds messed up and way over the OP's ability. The condition I'm suspecting here can be pretty damn dangerous and needs professional attention. Going about electrical work a bit here and a bit there is how wiring becomes a nightmare. People get tunnel vision and don't look at the system as a whole resulting in unbalanced panel power distribution, back feeds and plain old open circuits that are difficult to trace and repair.

And then you have what potentially seems like both phases in the same box. This is not impossible as the box may serve as a splice point for another circuit that has nothing to do with any device present at the box. I would look at box fill as well.

[cabmandone]

First, what panel doesn't have a main breaker? If there's nothing killing power at the panel, have that fixed. Having said that, turn off the breaker you need to pull, remove the wires, remove the breaker, install the new breaker, reconnect wires, turn on new breaker. Gloves? Not sure what good they really do. I never kill power at the main breaker when changing or adding breakers.

[masraum]

Originally Posted by cabmandone

First, what panel doesn't have a main breaker? If there's nothing killing power at the panel, have that fixed. Having said that, turn off the breaker you need to pull, remove the wires, remove the breaker, install the new breaker, reconnect wires, turn on new breaker. Gloves? Not sure what good they really do. I never kill power at the main breaker when changing or adding breakers.

I'm pretty sure that he replaced the breaker and discovered that the issue isn't with the breaker, but is with the circuit connected to it.

[Zeke]

Let's overthink this.

[cabmandone]

Originally Posted by masraum

I'm pretty sure that he replaced the breaker and discovered that the issue isn't with the breaker, but is with the circuit connected to it.

Okay. I just read his question in his OP and thought it odd that the panel didn't have a main breaker. I see above that he found the main. He said it's on an external panel. Must be sub panel.

Originally Posted by Zeke

Let's overthink this.

I think that's the best possible course of action. Analysis paralysis solves a lot of problems.

__________________________________________________ ___________________________

To back up a bit, what work was done that caused the breaker to trip? I've seen switches where the black wire was hot coming in and the white wire, which is typically neutral, was used to carry power to the light fixture or plug. Power came through the fixture or plug with a two wire with ground going to the switch.

[wilnj]

Originally Posted by cabmandone

First, what panel doesn't have a main breaker? If there's nothing killing power at the panel, have that fixed. Having said that, turn off the breaker you need to pull, remove the wires, remove the breaker, install the new breaker, reconnect wires, turn on new breaker. Gloves? Not sure what good they really do. I never kill power at the main breaker when changing or adding breakers.

You can order a panel MLO - Main Lug Only with no main breaker.

Typically if the panel is more than 10’ from the service entry point, you need an external breaker.

Thats the set up I have at home.

[jyl]

Forgot to post pic of exterior panel. Dark now, will do tmrw. It isn’t a normal residential service because this is a triplex. There is a big-ass panel on the exterior that says “400A” and has three meters, one for each unit. Next to each meter is a hinged cover labeled with the unit, and under that is the shutoff for that unit’s panel. My electrician was pleased to see it, and said “you have plenty of power”. Once she said that I lost interest in the big-ass panel since I didn’t plan to ever mess with it. But I looked more closely today.

Ok, on the circuit. Now that I’m done being irritated at myself for not taking a picture of the wiring before I disconnected everything and removed the old light - which was weeks ago - I think I understand how it is supposed to be wired.

I should have given it more thought but my main task today was to take the foyer walls to studs, and I needed to get on with that. Took about five hours with bagging and hauling to my dropbox and cleanup. Pulled off drywall then lath and plaster from the walls, and drywall from the ceiling. Found the former switch box, covered up, connected to knob and tube, still hot. Eeep. Screwed a scrap down to cover that and adding it to the list of things for my electrician to deal with.

Next week I am going to take off the rest of the ceilings of the foyer and kitchen. Maybe get started on the bathroom demo. It is crazy how much volume the demo’d stuff takes up when bagged. I’m gonna fill my third 10 yard box soon.

I hadn’t originally planned to fully demo the foyer, but they put drywall over wallpaper without resetting the trim and casings, and it looked bad, so I started pulling off drywall. Then I started thinking about all the work needed to do a good paint job over old wallpaper, and alternatively all the work needed to remove multiple layers of old wallpaper. Then I thought about how the coffee bar will be there so it will need many circuits and some plumbing, and I decided it will be faster for the electrician and plumber and therefore cheaper for me if the room was totally open to the studs. Plus I can insulate the exterior walls and recover the walls with firecode X drywall. It made sense, really.

[masraum]

Demo is huge, PITA, and generates an enormous amount of trash!

[look 171]

Oh man, I hate demo. Haven't done much of it really but everyone seem to like it to get their frustrations out. An old friend asked if she can be involve in the next demo because of her divorce. Sure, why not . I gave her a pair of gloves, googles, mask, a big hammer and a shovel. She lasted about 30 mins and I took her to breakfast instead. Never asked again.

Glad you were able to expose that J-box and knob and tube. There are lots of creative work buried in old duplex and other rental type buildings because most owners are cheap, seem to hire handy-man-deluxe to perform work that's a bit over their head and don't understand or know building codes.

[jyl]

Originally Posted by look 171

Oh man, I hate demo. Haven't done much of it really but everyone seem to like it to get their frustrations out. An old friend asked if she can be involve in the next demo because of her divorce. Sure, why not . I gave her a pair of gloves, googles, mask, a big hammer and a shovel. She lasted about 30 mins and I took her to breakfast instead. Never asked again.

Glad you were able to expose that J-box and knob and tube. There are lots of creative work buried in old duplex and other rental type buildings because most owners are cheap, seem to hire handy-man-deluxe to perform work that's a bit over their head and don't understand or know building codes.

Ha ha at your friend

This stuff is work. People who do it all day, day after day, are tougher stuff than me.

[Zeke]

Always did my own demo or worked with the crew. Leave it to idiots and they will create more work through damage. Take it apart, don't smash it apart. Cast iron tubs being an exception.

[look 171]

Originally Posted by Zeke

Always did my own demo or worked with the crew. Leave it to idiots and they will create more work through damage. Take it apart, don't smash it apart. Cast iron tubs being an exception.

Done little bit of it in my youth but dislike it so I hired out. Sure there are idiots that don't care or simply can't follow directions and that's the industry we are in. Anything important, I have my own employees perform that task especially with historical work but will hire someone to follow them around to clean things up immediately, haul trash out as demo is going on. My demo guy always has someone we can use for a few days hauling trash to the roll-off. Other then that, most of my jobs are gutted or at least half the house so have at it. Snag a wire, break a pipe. Its fine, we are replacing it anyway.

[jyl]

Here is my exterior panel.

The light works now. Yaay and thanks!

This is what I demo’d.




I was going to pull off the ceiling today, but got called to a friend’s coffee and food/gift shop to fix his espresso machine. It is an older commercial two group. I restored it several years ago and sold it to him for what I had in it, which was $400. Apparently that means whenever it breaks I get to rush over there and fix it. Sigh. Still, it’s not all for naught. They are giving us a Turbofan oven and will train us in sourcing and roasting coffee, and be our roaster until we are set up to self-roast.

[jyl]

It’s the cleanup I don’t like (for demo). Dirty and tedious, and the bags are endless, heavy, with sharp things sticking out. Semi-carefully detaching unwanted from wanted is slightly fun.

How do you handle an in-place cast iron tub. I don’t think I can lift and move that thing. I can sell the clawfoot tub, especially as it is a groovy 60’s color, but not so the built-in tub.

[dad911]

Originally Posted by jyl

.......
How do you handle an in-place cast iron tub. I don’t think I can lift and move that thing. I can sell the clawfoot tub, especially as it is a groovy 60’s color, but not so the built-in tub.

Hit it with a sledge hammer, it will break.

[look 171]

Originally Posted by dad911

Hit it with a sledge hammer, it will break.

This. Talking about sharp things. Careful and the small pieces are heavy aftrt a long tired day.

[look 171]

Originally Posted by jyl

It’s the cleanup I don’t like (for demo). Dirty and tedious, and the bags are endless, heavy, with sharp things sticking out. Semi-carefully detaching unwanted from wanted is slightly fun.

How do you handle an in-place cast iron tub. I don’t think I can lift and move that thing. I can sell the clawfoot tub, especially as it is a groovy 60’s color, but not so the built-in tub.

That's the real reason I hire someone to help with the clean up. My guys can remove or swing a big hammer but we always have someone following them around to haul things out in wheel barrels straight into the dump. Oh, they pull nails too, no fun

I don't want to burn my guys out doing the heavy lifting. Save them for the finer more complex skillful stuff.

[jyl]

Well, I usually like the opportunity to buy tools, but a sledgehammer does not excite me

I think I will Harbor Freight this purchase

[look 171]

Originally Posted by jyl

Well, I usually like the opportunity to buy tools, but a sledgehammer does not excite me

I think I will Harbor Freight this purchase

Funny. I use to be a tool junky and bought some very specialized, latest and the greatest tools and machines. After slowly hands off the fabrication part (miss it actually) I stopped buying and looking at tools and equipment slowly.

You can cut it out with a grinder if you like to torture yourself with a bit of hearing loss and vibration to your hands and arms. But the sledge is the best and fastest way. Sometimes, the old ways are best.