Help me not be the annoying new roommate who killed the house.
February 15, 2010 3:49 PM Subscribe
I am not an electrician. But I'm poor, and I'm not an idiot. Unfortunately, I think I did something stupid when wiring a new wall plug; I accidentally touched two wires together, and now the electricity is off in two rooms. More electrically savvy people: can you help me?
So I've been helping out around the house in the new place I just moved into, and part of that help has been fixing little stuff here and there. The kitchen outlet, for example, didn't work, and I found the short (in the recently-installed overhead light) and fixed it. Various very small stuff like that. I've done a lot of wiring of stuff before, though I'm obviously not a professional, so this small stuff has generally been easy.
Which leads to today; my new roommates at the place I just moved into had wanted a new lightswitch and outlet in their bathroom, since the old switch didn't work well and the old outlet was ugly. This being a pretty simple job, I thought I could do it - and I did, almost. These seemed like smaller jobs, and I wanted to get it done, so (perhaps being a royal idiot) I left the breaker on and just tried to be careful not to touch the wrong things and to only use my shielded pliers and screwdriver. Got the lightswitch all wired nicely and working well, and then I moved on to the corner outlet - and here, as I was cutting the wire, I apparently touched something, because there was a big flash and power in this bathroom and my roommates' bedroom went out.
Now I can't get power to come back on in those two rooms no matter what I try; I've tried wiring it again every which way, and checked the connections under both the lightswitch and the outlet, but nothing seems to do the trick. I've checked the circuit breaker outside, but none of the circuits have been tripped; I did the thing where I pushed all the breakers to 'on' (in case it wasn't tripped all the way) but it did nothing. So it's not the circuit breaker, apparently.
I'm worried primarily because this is a wonky old house with aluminum wiring; all the wires I've seen have been 12-gauge, which is good, but I hear things about short-circuits and such with this kind of wire - and the wire here looks pretty old to my eye.
Finally: the cheapest electrician we know costs $75. I have $3. I can beg that off from my roommates, but I'd really, really like it if there's some small thing here that I can do to find the fix and solve the problem. Like I said, I'm not a pro, but I'm also not an idiot, and I have decent tools; I have a good little voltage detector, for a start, so I guess I could go along the wall through each room looking for the short if I had to. Is there some easier way? Does anybody know what I should do? The biggest question, I guess, is: does anybody know what probably happened? When I cut an outlet wire, perhaps accidentally grounding it meanwhile, and a big spark occurred - and thereafter there was no power on that circuit - what could have happened?
So I've been helping out around the house in the new place I just moved into, and part of that help has been fixing little stuff here and there. The kitchen outlet, for example, didn't work, and I found the short (in the recently-installed overhead light) and fixed it. Various very small stuff like that. I've done a lot of wiring of stuff before, though I'm obviously not a professional, so this small stuff has generally been easy.
Which leads to today; my new roommates at the place I just moved into had wanted a new lightswitch and outlet in their bathroom, since the old switch didn't work well and the old outlet was ugly. This being a pretty simple job, I thought I could do it - and I did, almost. These seemed like smaller jobs, and I wanted to get it done, so (perhaps being a royal idiot) I left the breaker on and just tried to be careful not to touch the wrong things and to only use my shielded pliers and screwdriver. Got the lightswitch all wired nicely and working well, and then I moved on to the corner outlet - and here, as I was cutting the wire, I apparently touched something, because there was a big flash and power in this bathroom and my roommates' bedroom went out.
Now I can't get power to come back on in those two rooms no matter what I try; I've tried wiring it again every which way, and checked the connections under both the lightswitch and the outlet, but nothing seems to do the trick. I've checked the circuit breaker outside, but none of the circuits have been tripped; I did the thing where I pushed all the breakers to 'on' (in case it wasn't tripped all the way) but it did nothing. So it's not the circuit breaker, apparently.
I'm worried primarily because this is a wonky old house with aluminum wiring; all the wires I've seen have been 12-gauge, which is good, but I hear things about short-circuits and such with this kind of wire - and the wire here looks pretty old to my eye.
Finally: the cheapest electrician we know costs $75. I have $3. I can beg that off from my roommates, but I'd really, really like it if there's some small thing here that I can do to find the fix and solve the problem. Like I said, I'm not a pro, but I'm also not an idiot, and I have decent tools; I have a good little voltage detector, for a start, so I guess I could go along the wall through each room looking for the short if I had to. Is there some easier way? Does anybody know what I should do? The biggest question, I guess, is: does anybody know what probably happened? When I cut an outlet wire, perhaps accidentally grounding it meanwhile, and a big spark occurred - and thereafter there was no power on that circuit - what could have happened?
Response by poster: Yes, I am an idiot. Happily an alive idiot. Thanks, bricoleur.
posted by koeselitz at 3:56 PM on February 15, 2010
posted by koeselitz at 3:56 PM on February 15, 2010
Best answer: Jesus Christ, k, turn off the power BEFORE you fuck with wires. You can die. Seriously. Fuck. I don't care what it costs, just get an electrician. You are not allowed to work on these things anymore. This is a serious answer.
posted by Optimus Chyme at 3:57 PM on February 15, 2010 [30 favorites]
posted by Optimus Chyme at 3:57 PM on February 15, 2010 [30 favorites]
I'm questioning your contention you're not an idiot. Working on a live circuit? Seriously? Thank the universes' sense of humor you aren't dead and the house hasn't burned to the ground.
There are any number of things that could be wrong. If it was a simple short, then the breakers *should* trip. I'd guess that that old wire has burned through or otherwise broke someplace leaving no circuit. Get someone qualified to diagnose the issue.
posted by kjs3 at 3:59 PM on February 15, 2010
There are any number of things that could be wrong. If it was a simple short, then the breakers *should* trip. I'd guess that that old wire has burned through or otherwise broke someplace leaving no circuit. Get someone qualified to diagnose the issue.
posted by kjs3 at 3:59 PM on February 15, 2010
Best answer: Just echoing bricoleur, so maybe it will be twice as loud: never ever ever work on wiring unless the power is off at the breaker. Never.
And, yes, a breaker is probably tripped. You must turn each switch fully off, then back on. Just pushing it to the on position will absolutely not work if it's tripped.
posted by The Deej at 4:00 PM on February 15, 2010 [1 favorite]
And, yes, a breaker is probably tripped. You must turn each switch fully off, then back on. Just pushing it to the on position will absolutely not work if it's tripped.
posted by The Deej at 4:00 PM on February 15, 2010 [1 favorite]
Best answer: Yeah, flick them off and on again, and thank your lucky stars. Sometimes these things trip but don't trip the switch. You may need to replace the circuit breaker - you can usually switch them over fairly easily so may be able to tell if this is the case by switching off one that you know works, and putting it back in the place where the dead one is.
And don't do ANYTHING with the circuit live again. Seriously.
posted by handee at 4:02 PM on February 15, 2010
And don't do ANYTHING with the circuit live again. Seriously.
posted by handee at 4:02 PM on February 15, 2010
Response by poster: I'm thinking "don't handle ANYTHING with a CIRCUIT again" might make some sense.
I'm kicking myself pretty hard over this - argh. Anyway, thanks all.
posted by koeselitz at 4:04 PM on February 15, 2010
I'm kicking myself pretty hard over this - argh. Anyway, thanks all.
posted by koeselitz at 4:04 PM on February 15, 2010
There are a number of ways that you can get a bad shock from working with electricity. Don't just turn off the breaker and expect that the power is off, if you live in a house where a non-electrician has done some work. I had a fixture that was supplied by two breakers, for instance. I also had a fixture where the switch was on the black wire, not the white (hot) wire, so turning off the wall switch did not cut the power to the fixture.
110 volts will not usually kill you. I am still here, for instance. The lesson is, use a volt meter to make sure that the power is off, before you mess with the wires.
posted by Midnight Skulker at 4:07 PM on February 15, 2010
110 volts will not usually kill you. I am still here, for instance. The lesson is, use a volt meter to make sure that the power is off, before you mess with the wires.
posted by Midnight Skulker at 4:07 PM on February 15, 2010
Best answer: No need to be paranoid about anything electrical (it's really not that hard). But do make sure you know how to turn the power off BEFORE you start touching wires again.
Working on live wires makes as much sense as working on plumbing pipes without turning off the water. You wouldn't do THAT, would you?
posted by rokusan at 4:07 PM on February 15, 2010
Working on live wires makes as much sense as working on plumbing pipes without turning off the water. You wouldn't do THAT, would you?
posted by rokusan at 4:07 PM on February 15, 2010
the place I just moved into had wanted a new lightswitch and outlet in their bathroom
Did you check for popped GFIs in the bathroom? Only bringing this up because you mentioned you checked the breakers and you were working in a bathroom. Bathrooms generally have GFIs on outlets. Did you make sure the resets are pushed back in on all of them? usually GFIs are wired such that they only interrupt themselves, but sometimes they are wired so they break the whole circuit.
posted by jeb at 4:08 PM on February 15, 2010
Did you check for popped GFIs in the bathroom? Only bringing this up because you mentioned you checked the breakers and you were working in a bathroom. Bathrooms generally have GFIs on outlets. Did you make sure the resets are pushed back in on all of them? usually GFIs are wired such that they only interrupt themselves, but sometimes they are wired so they break the whole circuit.
posted by jeb at 4:08 PM on February 15, 2010
Response by poster: Okay, flipped all the breakers back and forth, and it was indeed a breaker which didn't flip all the way - everything works again.
Thanks, everybody. I'm just going to not do anything wiring-related for a while - and if I ever do again, breakers will be firmly OFF before starting.
Maybe this thread can be a handy lesson to somebody else, anyway: it's really, really stupid to do what I do. Take it from a dolt who's happy to not be fried right now.
posted by koeselitz at 4:09 PM on February 15, 2010
Thanks, everybody. I'm just going to not do anything wiring-related for a while - and if I ever do again, breakers will be firmly OFF before starting.
Maybe this thread can be a handy lesson to somebody else, anyway: it's really, really stupid to do what I do. Take it from a dolt who's happy to not be fried right now.
posted by koeselitz at 4:09 PM on February 15, 2010
I'm worried primarily because this is a wonky old house with aluminum wiring
Here, I'll give you something else to kick yourself over...
Old aluminum wiring and a brand-new lightswitch? Did you remember to coat the aluminum-to-copper contacts with an anti-oxidant, anti-corrosion paste?
posted by Cool Papa Bell at 4:10 PM on February 15, 2010
Here, I'll give you something else to kick yourself over...
Old aluminum wiring and a brand-new lightswitch? Did you remember to coat the aluminum-to-copper contacts with an anti-oxidant, anti-corrosion paste?
posted by Cool Papa Bell at 4:10 PM on February 15, 2010
Response by poster: Cool Papa Bell: “Old aluminum wiring and a brand-new lightswitch? Did you remember to coat the aluminum-to-copper contacts with an anti-oxidant, anti-corrosion paste?”
Good point, but thankfully I didn't need to - little copper wire lengths are already pigtailed on, thankfully. I guess it's possible that wasn't done right, but it looks pretty solid.
Again, thanks all.
posted by koeselitz at 4:12 PM on February 15, 2010
Good point, but thankfully I didn't need to - little copper wire lengths are already pigtailed on, thankfully. I guess it's possible that wasn't done right, but it looks pretty solid.
Again, thanks all.
posted by koeselitz at 4:12 PM on February 15, 2010
Not to pile on or anything but I learned this lesson (turn off the power at the breaker) the hard way when I was a kid. I fused the tip of a screwdriver to an electrical switch and nearly killed myself.
I'm glad you got to learn the lesson instead of being the lesson for others to learn from.
posted by fenriq at 4:14 PM on February 15, 2010 [1 favorite]
I'm glad you got to learn the lesson instead of being the lesson for others to learn from.
posted by fenriq at 4:14 PM on February 15, 2010 [1 favorite]
One more comment - Did you wire the bathroom outlet to a GFI protected circuit?
Find the GFI, push the test button and make sure the outlet you wired goes dead. If not, it should really be replaced with a GFI outlet - or someone else in the bathroom may be seriously injured (or worse) in the future.
posted by NoDef at 4:43 PM on February 15, 2010
Find the GFI, push the test button and make sure the outlet you wired goes dead. If not, it should really be replaced with a GFI outlet - or someone else in the bathroom may be seriously injured (or worse) in the future.
posted by NoDef at 4:43 PM on February 15, 2010
koeselitz, here's your darwin award.
glad we're not all in metatalk goin' all moany and weepy about the late koeselitz
posted by Kerasia at 5:11 PM on February 15, 2010 [1 favorite]
glad we're not all in metatalk goin' all moany and weepy about the late koeselitz
posted by Kerasia at 5:11 PM on February 15, 2010 [1 favorite]
Best answer: Midnight Skulker writes "I also had a fixture where the switch was on the black wire, not the white (hot) wire, so turning off the wall switch did not cut the power to the fixture. "
FYI this is no longer considered sufficient; you must only connect aluminum wire to fixtures (lights, switches, outlets, etc) that specifically say they are rated for aluminum. If it doesn't say Cu/Al or only says Cu then it should not be connected to aluminum wire. Because Cu/Al fixtures cost more than straight Cu fixtures it's generally cheaper to pig tail a piece of coper to make the connection at the fixture.
posted by Mitheral at 5:33 PM on February 15, 2010
- White is generally neutral not hot
- Despite the above sometimes when everything is wired correctly the white wire will be hot. This is by design so that when everything is said and done the white wire at the fixture can be connected with the shell of the light fixture.
- If power enters the fixture before the switch or the fixture is on a split circuit then turning off the switch does not turn off the power at the fixture. IE: Do not depend on the switch to cut power, always trip the breaker.
- Further to above, residential wiring tends to be DIY'd a lot and mostly incorrectly. Always check for power in a box after removing the face plate but before going any further.
FYI this is no longer considered sufficient; you must only connect aluminum wire to fixtures (lights, switches, outlets, etc) that specifically say they are rated for aluminum. If it doesn't say Cu/Al or only says Cu then it should not be connected to aluminum wire. Because Cu/Al fixtures cost more than straight Cu fixtures it's generally cheaper to pig tail a piece of coper to make the connection at the fixture.
posted by Mitheral at 5:33 PM on February 15, 2010
Data point: when I was about ten, at a friend's house, I touched a box fan's metal enclosure that was against a frayed wire. I don't know how I completed the circuit, but I did, and was thrown over a coffee table. How much of that was reflex, how much was a spasm, I don't know. But I was lucky that it was only a fingertip and not my hands wrapped around a tool. Even with breakers off you have to test the current with a multimeter to make sure you're not going to kill youself. I hope this thread serves as an object lesson: it really can happen to you.
posted by Optimus Chyme at 6:32 PM on February 15, 2010
posted by Optimus Chyme at 6:32 PM on February 15, 2010
O.P. -- Please read this: http://www.ehow.com/how_5431938_test-live-wire.html.
You can buy live wire testers for not very much from Home Depot, and eBay has them for $5.99.
posted by lungtaworld at 6:57 PM on February 15, 2010
You can buy live wire testers for not very much from Home Depot, and eBay has them for $5.99.
posted by lungtaworld at 6:57 PM on February 15, 2010
PLEASE IGNORE MIDNIGHT SKULKER
Black is Hot!!!!
White is Neutral
Green or Bare is Ground
This is for most three wire circuits
Sometimes when you have a three way switch the wire running between the two switches (the wire that lets you turn the circuit on or off at either switch) is run so that at times the white may be hot and at other times the black may be hot.
...and
110 volts can kill you easily. Just like a bullet, it depends on where the voltage is running. You can shoot yourself in the foot and live, you can shoot yourself in the heart and die. You can get 110 volts across a single finger and live, you can get it across that finger and your foot on the wet floor and die.
posted by leafwoman at 7:24 PM on February 15, 2010
Black is Hot!!!!
White is Neutral
Green or Bare is Ground
This is for most three wire circuits
Sometimes when you have a three way switch the wire running between the two switches (the wire that lets you turn the circuit on or off at either switch) is run so that at times the white may be hot and at other times the black may be hot.
...and
110 volts can kill you easily. Just like a bullet, it depends on where the voltage is running. You can shoot yourself in the foot and live, you can shoot yourself in the heart and die. You can get 110 volts across a single finger and live, you can get it across that finger and your foot on the wet floor and die.
posted by leafwoman at 7:24 PM on February 15, 2010
Don't just the labels on the circuit breakers - spend a few bucks on a tester to make sure the circuit is dead (or at least confirm that the breaker will turn off a lamp plugged into the outlet in question). I had quite a shock once when I thought I turned off the power to an electric stove.
posted by exogenous at 7:56 PM on February 15, 2010
posted by exogenous at 7:56 PM on February 15, 2010
Arg - I meant to write don't *trust* the labels on the circuit breakers.
posted by exogenous at 8:05 PM on February 15, 2010
posted by exogenous at 8:05 PM on February 15, 2010
Just to clarify: it sounds like the circuit breaker was tripped "all the way." Circuit breakers have three settings: on, off, and tripped; tripped is not the same as off (well, it's the same in that the power is cut, but they're different positions). You can't switch a tripped circuit breaker directly to "on." You have to switch it off first, then on. That's how they're supposed to work.
posted by DevilsAdvocate at 8:07 PM on February 15, 2010
posted by DevilsAdvocate at 8:07 PM on February 15, 2010
When we moved in to our first old house we had a ton of issues with wiring, including live lamp cord (with bare ends) directly under the gyproc in the walls. We knew from that to replace what we could ASAP. I started doing it on my own, reading up in the library about the basic theory, practice and code requirements. Did most of the tasks that can be done by a non-electrician. But when we came across two circuits cross-connected I gave up and took out a loan to get the pros in and finish the extra tricky bits. Good thing too; it turned out even our GFCI wasn't wired properly and wouldn't have protected us.
What I'm saying is that wiring is simple to fix only when it's designed simply, and properly, and safely. Even if all these things are true you can't stray outside your comfort level. If at any point you don't have a good answer to the questions 'is this right' and 'can anything go wrong' - stop, drop tools, and call for help.
This tool was invaluable in determining where the problems were, and prevented me from making the mistake of working on one of the crossed circuits (I would have turned off what I thought was the only breaker, and the crossed circuit would still be sending juice). You plug it in to any outlet and it will tell you if voltage is present on any of the lines, whether the hot and neutral are wired incorrectly, whether there are any ground problems, and several other serious flaws with the circuit. $10 and easy to use.
Nthing the extra caution with matching aluminum-ready receptacles. This ups the complexity and makes the electrician mandatory IMO.
posted by Hardcore Poser at 9:21 PM on February 15, 2010
What I'm saying is that wiring is simple to fix only when it's designed simply, and properly, and safely. Even if all these things are true you can't stray outside your comfort level. If at any point you don't have a good answer to the questions 'is this right' and 'can anything go wrong' - stop, drop tools, and call for help.
This tool was invaluable in determining where the problems were, and prevented me from making the mistake of working on one of the crossed circuits (I would have turned off what I thought was the only breaker, and the crossed circuit would still be sending juice). You plug it in to any outlet and it will tell you if voltage is present on any of the lines, whether the hot and neutral are wired incorrectly, whether there are any ground problems, and several other serious flaws with the circuit. $10 and easy to use.
Nthing the extra caution with matching aluminum-ready receptacles. This ups the complexity and makes the electrician mandatory IMO.
posted by Hardcore Poser at 9:21 PM on February 15, 2010
Let me tell you a story about a brand new dryer. The hookup in our basement was actually a stove outlet, not a dryer outlet, tho this is a common mistake.
The right answer was "because the power cables on stoves and dryers are interchangeable, and you need to buy and install it anyway. The ones for stoves work great on dryers." - most pros would have just told me this over the phone, no charge, if I had bothered to call one.
The answer I chose was "I need to upgrade to a dryer outlet to get the dryer to work. I've read how to do this online!"
So! I buy a nice dryer outlet at the Home Despot, and then go to work! I locate the circuit breaker on the panel labeled "Dryer", shut it off, and tape it off for the duration of the project. I fish out my outlet tester from the toolbag - hey, no light!
The right answer was "test the outlet tester on another outlet you know is live to make sure it's working."
The answer I chose was, "Let's take apart the old outlet and install the new one."
I have a screw driver with a crater melted halfway through it as a reminder to call a fucking professional to get killed instead of me because the breakers are mislabeled.
I'm a DIY kinda guy, but if I fuck up swapping out the sparkplugs, the car simply won't start - it won't kill me and eat my children the way AC current would if I fuck up. Part of the problem is that my Dad is an electrical engineer with an electrician's license - I saw him do this stuff around the house all the time without fear or worry. This is because he knew, stone cold, what to do, how to do it, and stay breathing while he did it. This takes experience and training. It's worth the cash to have a pro do it.
posted by Slap*Happy at 9:32 PM on February 15, 2010
The right answer was "because the power cables on stoves and dryers are interchangeable, and you need to buy and install it anyway. The ones for stoves work great on dryers." - most pros would have just told me this over the phone, no charge, if I had bothered to call one.
The answer I chose was "I need to upgrade to a dryer outlet to get the dryer to work. I've read how to do this online!"
So! I buy a nice dryer outlet at the Home Despot, and then go to work! I locate the circuit breaker on the panel labeled "Dryer", shut it off, and tape it off for the duration of the project. I fish out my outlet tester from the toolbag - hey, no light!
The right answer was "test the outlet tester on another outlet you know is live to make sure it's working."
The answer I chose was, "Let's take apart the old outlet and install the new one."
I have a screw driver with a crater melted halfway through it as a reminder to call a fucking professional to get killed instead of me because the breakers are mislabeled.
I'm a DIY kinda guy, but if I fuck up swapping out the sparkplugs, the car simply won't start - it won't kill me and eat my children the way AC current would if I fuck up. Part of the problem is that my Dad is an electrical engineer with an electrician's license - I saw him do this stuff around the house all the time without fear or worry. This is because he knew, stone cold, what to do, how to do it, and stay breathing while he did it. This takes experience and training. It's worth the cash to have a pro do it.
posted by Slap*Happy at 9:32 PM on February 15, 2010
As someone who got hooked up to her house's electrical current at age six because of a faulty lightswitch installation (and has the scars to prove it), I can only add my voice to the chorus: only let licensed electricians deal with these sorts of things.
Even if you had the power off and had gotten through your installation seemingly fine, a faulty installation could cause damage or injury later—years later, sometimes. (The garage lightswitch which gave me my electric shock—I got my hand caught on and cut up by an electrified screw sticking out of the casing—had been installed years before my family inhabited the house. If my mom hadn't been in the next room and heard me moaning "like a dying cow," as she put it, I might have been dead for nearly twenty years by now.)
posted by ocherdraco at 12:07 AM on February 16, 2010 [1 favorite]
Even if you had the power off and had gotten through your installation seemingly fine, a faulty installation could cause damage or injury later—years later, sometimes. (The garage lightswitch which gave me my electric shock—I got my hand caught on and cut up by an electrified screw sticking out of the casing—had been installed years before my family inhabited the house. If my mom hadn't been in the next room and heard me moaning "like a dying cow," as she put it, I might have been dead for nearly twenty years by now.)
posted by ocherdraco at 12:07 AM on February 16, 2010 [1 favorite]
I don't have yet another anecdote to pile on, but am wondering: Did turning the breakers off and on again now fix the issue? I thought the original question said that he tried it and it didn't work?
posted by themel at 1:20 AM on February 16, 2010
posted by themel at 1:20 AM on February 16, 2010
Please Ignore Leafwoman. In most cases three-way switches should be wired with three wire cable (black, red, white + ground). The carrier is the red wire, never the white which is still neutral.
Unless its really old wiring and then there are a number of different things that could happen.
The case MidnightSkulker is describing sounds like what is commonly described as a "switch leg".
posted by buttercup at 2:25 AM on February 16, 2010
Unless its really old wiring and then there are a number of different things that could happen.
The case MidnightSkulker is describing sounds like what is commonly described as a "switch leg".
posted by buttercup at 2:25 AM on February 16, 2010
Response by poster: Midnight Skulker: “I also had a fixture where the switch was on the black wire, not the white (hot) wire, so turning off the wall switch did not cut the power to the fixture.”
Mitheral: “White is generally neutral not hot ¶ Despite the above sometimes when everything is wired correctly the white wire will be hot. This is by design so that when everything is said and done the white wire at the fixture can be connected with the shell of the light fixture.”
leafwoman: “PLEASE IGNORE MIDNIGHT SKULKER ¶ Black is Hot!!!! ¶ White is Neutral ¶ Green or Bare is Ground ¶ This is for most three wire circuits”
buttercup: “Please Ignore Leafwoman. In most cases three-way switches should be wired with three wire cable (black, red, white + ground). The carrier is the red wire, never the white which is still neutral.”
With all due respect, I think Mitheral has it, along with buttercup: you're all right. Unfortunately. The thing is, there is no standard that's used widely enough for us all to just accept it. You simply have to use a tester and pay attention to the way the last person wired it.
(Relax, leafwoman; I think it's pretty clear that Midnight Skulker wasn't saying all circuits are wired that way. It sounds like he just meant that he dealt with one that was. Which just goes to show - you never know. You just have to watch what you're doing, check on the fixture you're removing if you can, and test it with a tester if you can't.)
Mitheral: “FYI this is no longer considered sufficient; you must only connect aluminum wire to fixtures (lights, switches, outlets, etc) that specifically say they are rated for aluminum. If it doesn't say Cu/Al or only says Cu then it should not be connected to aluminum wire. Because Cu/Al fixtures cost more than straight Cu fixtures it's generally cheaper to pig tail a piece of coper to make the connection at the fixture.”
Which is what we've got here at the house. Furthermore, you're right that just a coat of non-corrosive isn't quite sufficient; however, my understanding is that what's needed is at least two-gauge thicker Al connecting to the Cu. That is, for example, in our house, we have 12-gauge Al pigtailed to 14-gauge Cu, since the Cu can handle a greater potential per gauge point. Just by the way, do you know if there's anything else that I should look for when checking for faulty circuits in here?
Anyhow, thanks all. I really do know some about electrical stuff, but I guess this is a good lesson for me and for anybody else who stumbles on this thread: you can know a few things and still do something really, really stupid that might be dangerous. Never stop being careful, eh?
posted by koeselitz at 3:36 AM on February 16, 2010
Mitheral: “White is generally neutral not hot ¶ Despite the above sometimes when everything is wired correctly the white wire will be hot. This is by design so that when everything is said and done the white wire at the fixture can be connected with the shell of the light fixture.”
leafwoman: “PLEASE IGNORE MIDNIGHT SKULKER ¶ Black is Hot!!!! ¶ White is Neutral ¶ Green or Bare is Ground ¶ This is for most three wire circuits”
buttercup: “Please Ignore Leafwoman. In most cases three-way switches should be wired with three wire cable (black, red, white + ground). The carrier is the red wire, never the white which is still neutral.”
With all due respect, I think Mitheral has it, along with buttercup: you're all right. Unfortunately. The thing is, there is no standard that's used widely enough for us all to just accept it. You simply have to use a tester and pay attention to the way the last person wired it.
(Relax, leafwoman; I think it's pretty clear that Midnight Skulker wasn't saying all circuits are wired that way. It sounds like he just meant that he dealt with one that was. Which just goes to show - you never know. You just have to watch what you're doing, check on the fixture you're removing if you can, and test it with a tester if you can't.)
Mitheral: “FYI this is no longer considered sufficient; you must only connect aluminum wire to fixtures (lights, switches, outlets, etc) that specifically say they are rated for aluminum. If it doesn't say Cu/Al or only says Cu then it should not be connected to aluminum wire. Because Cu/Al fixtures cost more than straight Cu fixtures it's generally cheaper to pig tail a piece of coper to make the connection at the fixture.”
Which is what we've got here at the house. Furthermore, you're right that just a coat of non-corrosive isn't quite sufficient; however, my understanding is that what's needed is at least two-gauge thicker Al connecting to the Cu. That is, for example, in our house, we have 12-gauge Al pigtailed to 14-gauge Cu, since the Cu can handle a greater potential per gauge point. Just by the way, do you know if there's anything else that I should look for when checking for faulty circuits in here?
Anyhow, thanks all. I really do know some about electrical stuff, but I guess this is a good lesson for me and for anybody else who stumbles on this thread: you can know a few things and still do something really, really stupid that might be dangerous. Never stop being careful, eh?
posted by koeselitz at 3:36 AM on February 16, 2010
Hey k, I know you're getting all self-loathing and repentant about this right now, but for future reference and just in case you get another cowboy hair up your ass down the line:
Right now, this second, take your left hand. Reach back and rest it at the small of your back. Maybe hook your thumb into your belt or something. Okay, got it? Hold this position for a second. Alright: Whenever you are near something that's got juice in it and contemplating screwing around with it, assume this position before you proceed. Make this reflexive.
How come? Your heart's on the left side. If you can't resist poking things that might be live, at least don't complete a circuit across your ticker, okay?
posted by majick at 5:13 AM on February 16, 2010 [3 favorites]
Right now, this second, take your left hand. Reach back and rest it at the small of your back. Maybe hook your thumb into your belt or something. Okay, got it? Hold this position for a second. Alright: Whenever you are near something that's got juice in it and contemplating screwing around with it, assume this position before you proceed. Make this reflexive.
How come? Your heart's on the left side. If you can't resist poking things that might be live, at least don't complete a circuit across your ticker, okay?
posted by majick at 5:13 AM on February 16, 2010 [3 favorites]
leafwoman writes "Black is Hot!!!!"White is Neutral "Green or Bare is Ground"This is for most three wire circuits"
A little terminology: House wire is referred to by wire gauge and number of conductors (ground is assumed and not counted). Common sizes are 14/2, 12/2 (collectively 14-12/2), 14/3, 12/3, 10/3, 8/3 and 6/3. The first number is gauge size (smaller number = thicker wire) and the second the number of conductors. IE: a piece of 12/3 (pronounced twelve three) will have four individual wires, three conductors and an uninsulated ground wire. A cable with a black, white and bare ground is used in two wire circuits.
Slap*Happy writes "The right answer was 'because the power cables on stoves and dryers are interchangeable, and you need to buy and install it anyway. The ones for stoves work great on dryers.' - most pros would have just told me this over the phone, no charge, if I had bothered to call one."
Too be clear they are only 50% interchangeable. It is fine to use a stove cord on a dryer; and it is fine to install a dryer receptacle on a stove circuit. It is not fine to install a stove outlet on a dryer circuit or use a dryer cord on a stove. This is because a stove and it's circuit are designed to handle 25% more current than a dryer. Using a stove on a dryer circuit is a recipe for a house fire.
buttercup writes "In most cases three-way switches should be wired with three wire cable (black, red, white + ground). The carrier is the red wire, never the white which is still neutral."
This page shows eight different ways 3-way switches can be wired; five of them have a white wire being hot in at least one box. Admittedly there is some pretty weird stuff on that page but the first two variations are the most and the second has a hot white conductor.
FYI a ceiling fan where the power comes first into the fixture box can also have a hot white at the switches if a three conductor wire is used.
koeselitz writes "however, my understanding is that what's needed is at least two-gauge thicker Al connecting to the Cu. That is, for example, in our house, we have 12-gauge Al pigtailed to 14-gauge Cu, since the Cu can handle a greater potential per gauge point."
This wouldn't fly here, YJMV, and I wouldn't do it even if it was allowed. The reason Al rated fixtures/outlets/switches are required is the aluminum expands and contracts from heat (caused by current flow) more than copper. Aluminum fixtures are designed (often with wave springs) to handle this expansion without deforming the aluminum. This is important because the deformation causes arcing.
Generally though, with the exception of terminating an already pigtailed with copper connection, don't mess with aluminum wiring. It's one of those things where there isn't any substitute for training and experience.
posted by Mitheral at 7:51 AM on February 16, 2010 [3 favorites]
A little terminology: House wire is referred to by wire gauge and number of conductors (ground is assumed and not counted). Common sizes are 14/2, 12/2 (collectively 14-12/2), 14/3, 12/3, 10/3, 8/3 and 6/3. The first number is gauge size (smaller number = thicker wire) and the second the number of conductors. IE: a piece of 12/3 (pronounced twelve three) will have four individual wires, three conductors and an uninsulated ground wire. A cable with a black, white and bare ground is used in two wire circuits.
Slap*Happy writes "The right answer was 'because the power cables on stoves and dryers are interchangeable, and you need to buy and install it anyway. The ones for stoves work great on dryers.' - most pros would have just told me this over the phone, no charge, if I had bothered to call one."
Too be clear they are only 50% interchangeable. It is fine to use a stove cord on a dryer; and it is fine to install a dryer receptacle on a stove circuit. It is not fine to install a stove outlet on a dryer circuit or use a dryer cord on a stove. This is because a stove and it's circuit are designed to handle 25% more current than a dryer. Using a stove on a dryer circuit is a recipe for a house fire.
buttercup writes "In most cases three-way switches should be wired with three wire cable (black, red, white + ground). The carrier is the red wire, never the white which is still neutral."
This page shows eight different ways 3-way switches can be wired; five of them have a white wire being hot in at least one box. Admittedly there is some pretty weird stuff on that page but the first two variations are the most and the second has a hot white conductor.
FYI a ceiling fan where the power comes first into the fixture box can also have a hot white at the switches if a three conductor wire is used.
koeselitz writes "however, my understanding is that what's needed is at least two-gauge thicker Al connecting to the Cu. That is, for example, in our house, we have 12-gauge Al pigtailed to 14-gauge Cu, since the Cu can handle a greater potential per gauge point."
This wouldn't fly here, YJMV, and I wouldn't do it even if it was allowed. The reason Al rated fixtures/outlets/switches are required is the aluminum expands and contracts from heat (caused by current flow) more than copper. Aluminum fixtures are designed (often with wave springs) to handle this expansion without deforming the aluminum. This is important because the deformation causes arcing.
Generally though, with the exception of terminating an already pigtailed with copper connection, don't mess with aluminum wiring. It's one of those things where there isn't any substitute for training and experience.
posted by Mitheral at 7:51 AM on February 16, 2010 [3 favorites]
what do you mean Hot anyway? its AC current so they are both active no?
posted by mary8nne at 9:02 AM on February 16, 2010
posted by mary8nne at 9:02 AM on February 16, 2010
Hot means, in rough terms, that there is a voltage potential between the wire and ground. With a standard two wire circuit servicing say an unswitched outlet the white wire is neutral and has no voltage potential relative to ground. Attach a meter to ground and then touch the second probe to the white wire and the meter will read zero volts. Touch the lead to the black wire and you'll get ~115V.
Because of the lack of potential on the neutral line in theory (heavy on the theory) you can walk up to live electrical cable and touch the white wire with no ill effects. In practice between incorrect installations and specific failure modes doing so would be very dangerous.
This by the way is why polarized plugs exists (the wide blade will only connect to the white/neutral connection in the outlet). Also the neutral wire should always be connected to the shell of a lamp base with the hot wire going to the centre connection.
posted by Mitheral at 12:43 PM on February 16, 2010 [1 favorite]
Because of the lack of potential on the neutral line in theory (heavy on the theory) you can walk up to live electrical cable and touch the white wire with no ill effects. In practice between incorrect installations and specific failure modes doing so would be very dangerous.
This by the way is why polarized plugs exists (the wide blade will only connect to the white/neutral connection in the outlet). Also the neutral wire should always be connected to the shell of a lamp base with the hot wire going to the centre connection.
posted by Mitheral at 12:43 PM on February 16, 2010 [1 favorite]
This thread is closed to new comments.
And you are damn lucky you're still alive. Do not work on live circuits if you want to satay that way.
posted by bricoleur at 3:52 PM on February 15, 2010 [3 favorites]