? about replacing a light fixture

lionheartednyhc

macrumors 65816
Original poster
Jul 13, 2009
1,024
3
I plan on replacing the ceiling light in my apartment. I have never done anything electrical before, but it seems pretty straightforward. My question is, is it acceptable to use the light switch as a way to kill power to the fixture instead of going to the circuit breaker? Since Im in an apartment, access to the breaker is not exactly easy.

Thanks
 

Zombie Acorn

macrumors 65816
Feb 2, 2009
1,301
9,062
Toronto, Ontario
I plan on replacing the ceiling light in my apartment. I have never done anything electrical before, but it seems pretty straightforward. My question is, is it acceptable to use the light switch as a way to kill power to the fixture instead of going to the circuit breaker? Since Im in an apartment, access to the breaker is not exactly easy.

Thanks
I would flip the switch on the breaker, you are one small connector away from the shock of your life otherwise. I have done it before, but I wouldn't advise it, at the very least make sure the wire is dead before you go in with your hands.
 

GoCubsGo

macrumors Nehalem
Feb 19, 2005
35,743
141
No kill power at the breaker. After installing three fans all I can say is trust me.
 

Huntn

macrumors demi-god
May 5, 2008
17,060
16,567
The Misty Mountains
I worked my way through college as an electrician so I know enough to answer this question. :) If you are a novice, or even if you are not, the easiest way to deal with this is to trip the circuit breaker. The reason is that some ceiling fixtures have the hot wire coming into the fixture, then run a wire down to the switch. You could still end up handling a hot wire at the fixture.

Some fixtures are wired with the hot wire coming into the switch, then a wire up and back to the switch. This would be safer to work with at the fixture, but it's easier to kill the CB.

If I was doing this job I would verify without a doubt there are no hot wires by using an inexpensive amp-meter, set it to read AC volts then test wires. If you are wondering if you are using the AC meter correctly, test it on a wall receptical, one lead into each side. It should read about 120 volts. Get the guy at the store to show you. ;)

With a new fixture, it's important that you ground the fixture itself. Usually there is a little green screw in the electrical box and a green wire on the light fixture. You can connect a wire from this to the ground wire (bare wire) in the ceiling electrical box.

Although you might think the black wires are always hot, and the white wires are always neutral, that is not true. White wires can be hot if used for the wall switch. And white wire bundles, although they are neutral can still shock you if they are taking excess power back to ground. Antother reason to trip the CB. :)

Feel free to ask more questions.
 

lionheartednyhc

macrumors 65816
Original poster
Jul 13, 2009
1,024
3
Crap. Ok. I dont think I have acess to the breaker, is the problem :/
Even if I test it and it shows its dead (after hitting the switch), still advise to not touch it unless I can get to the breaker?
 

Zombie Acorn

macrumors 65816
Feb 2, 2009
1,301
9,062
Toronto, Ontario
Crap. Ok. I dont think I have acess to the breaker, is the problem :/
Even if I test it and it shows its dead (after hitting the switch), still advise to not touch it unless I can get to the breaker?
No one is going to advise you to do it because you could potentially kill yourself, if you know how to use a multimeter you should be fine.
 

lionheartednyhc

macrumors 65816
Original poster
Jul 13, 2009
1,024
3
No one is going to advise you to do it because you could potentially kill yourself, if you know how to use a multimeter you should be fine.

haha, of course. I guess that was my question, in regards to the multimeter.

Thanks.
 

-aggie-

macrumors P6
Jun 19, 2009
16,793
50
Where bunnies are welcome.
I worked my way through college as an electrician so I know enough to answer this question. :) If you are a novice, the best way to deal with this is to trip the circuit breaker. The reason is that some ceiling fixtures have the hot wire coming into the fixture, then run a wire down to the switch. You could still end up handling a hot wire at the fixture.

Some fixtures are wired with the hot wire coming into the switch, then a wire up and back to the switch. This would be safer to work with at the fixture, but it's just easier to kill the CB.

If you are wondering if wires are hot, you can always buy an inexpensive amp-meter, set it to read AC current then test wires.

With a new fixture, it's important that you ground the fixture itself. Usually there is a little green screw. You can connect a wire from this to the ground wire (bare wire) in the ceiling electrical box. Feel free to ask more questions. :)
Well, I actually was an electrician until I got my degree. You're exactly right.

Crap. Ok. I dont think I have acess to the breaker, is the problem :/
Even if I test it and it shows its dead (after hitting the switch), still advise to not touch it unless I can get to the breaker?
IDK whether to advise you or not, since you have no experience at all. However, since you'll probably do it anyway, here goes: It's very advisable that you kill power at the breaker. If you can't do that, twist off the wirenuts at the fixture, being careful not to touch the live wires, use a meter to check if there's voltage and then short the black and white wires with a screwdriver (where the handle is non-conductive) to even be more sure. You could also use a tick tracer to touch to each of the wires to see if they're live before shorting (it beeps and lights up if there's voltage). Of course if you get to the point where you use the screwdriver and it does actually short, your breaker will trip (the one you have no access to), HOWEVER YOU WILL BE ALIVE. Good luck, and the rest should be fairly easy. Just put everything back the way it was. I also electrical tape the wire nuts on after twisting them on tight. Many don't bother, but it makes sure they don't come off.

If you get stuck, ask questions, don't just wing it.
 

Huntn

macrumors demi-god
May 5, 2008
17,060
16,567
The Misty Mountains
Crap. Ok. I dont think I have acess to the breaker, is the problem :/
Even if I test it and it shows its dead (after hitting the switch), still advise to not touch it unless I can get to the breaker?
When you take off the ceiling fixture, if you just see two wires coming into the box, when you turn off the fixture using wall switch you should be safe, but that is not a 100% guarantee. However in this case I would use an amp-meter to be sure.

You can work with live wires if there is no other way, but it requires care, and novice electricians should avoid that.

Thinking about this, you have friends who know wiring? If so, it would be really better if you had someone who knows what they are doing helping you. House wiring is not that hard, after you've seen it done, but if you have no idea, I can imagine someone getting shocked or wiring the fixture wrong, or not getting the wires connected tightly. Yes most likely it will be easy to replace the fixture, but it would be better to have someone involved who is familiar with wiring.
 

lionheartednyhc

macrumors 65816
Original poster
Jul 13, 2009
1,024
3
Ok, awesome. Thanks guys. Ill let ya know what I do, or if I have any other questions!
 

Abstract

macrumors Penryn
Dec 27, 2002
24,378
110
Location Location Location
It doesn't matter whether you have access to the breakers or not. Trip them, work quick, and then call the building maintenance people to tell them about the awful circuit breaker that interrupted your favourite re-run of Ally McBeal. ;)
 

Surely

Guest
Oct 27, 2007
15,043
8
Los Angeles, CA
Crap. Ok. I dont think I have acess to the breaker, is the problem :/
Even if I test it and it shows its dead (after hitting the switch), still advise to not touch it unless I can get to the breaker?
Are you sure there isn't a breaker box somewhere in your apartment? There has been one in every apartment I've ever lived in.....
 

Gregg2

macrumors 603
May 22, 2008
5,809
344
Milwaukee, WI
Turn everything off, absolutely everything! Especially if it's an older apartment building, you have no idea if the labels on the circuits are correct.
 

GoCubsGo

macrumors Nehalem
Feb 19, 2005
35,743
141
Are you sure there isn't a breaker box somewhere in your apartment? There has been one in every apartment I've ever lived in.....
I was going to ask the same thing but I am in the US and it could vary by country I guess.
Usually mine are in the laundry room if I have one, in my place now it is actually in the spare bedroom (office) behind the door. Honestly, I'd be a bit annoyed if I moved in here intending to stay in the room with this bitch on my wall measuring 15" x 35". :eek:
IMG_2410.jpg


Anyway lionheartednyh, you won't die if you get shocked but in my case it really phased me.
 

Surely

Guest
Oct 27, 2007
15,043
8
Los Angeles, CA
Since you showed us yours.....

Mine's pretty bad too.... it's at eye-level, directly across from the master bedroom's door, so it's the first thing you see when you leave the bedroom. I may try to find a picture to cover it. I wish they would have just painted it.....it looks like they painted the bottom right corner at least...:rolleyes:
 

Attachments

lionheartednyhc

macrumors 65816
Original poster
Jul 13, 2009
1,024
3
I was going to ask the same thing but I am in the US and it could vary by country I guess.
Usually mine are in the laundry room if I have one, in my place now it is actually in the spare bedroom (office) behind the door. Honestly, I'd be a bit annoyed if I moved in here intending to stay in the room with this bitch on my wall measuring 15" x 35". :eek:
View attachment 209972


Anyway lionheartednyh, you won't die if you get shocked but in my case it really phased me.
Nice. The building Im living in is a converted house, so the the breaker is in someone elses apartment...
 

Zombie Acorn

macrumors 65816
Feb 2, 2009
1,301
9,062
Toronto, Ontario
It could be worse, my old house had the breaker box mounted outside (I had never see this before). Thats a nice thing to deal with in the middle of winter if you blow a breaker.
 

mwchris

macrumors regular
Apr 12, 2008
155
4
Kentucky
Turn everything off, absolutely everything! Especially if it's an older apartment building, you have no idea if the labels on the circuits are correct.

This is not necessary. Turn on the light you are going to change, go flip the breaker, if the light is off you have killed the power to it. Or you can check it with a volt meter.

Silly advice.
 

mwchris

macrumors regular
Apr 12, 2008
155
4
Kentucky
Nice. The building Im living in is a converted house, so the the breaker is in someone elses apartment...
Knowing this, I would recommend you not trip the breaker. You might trip the breaker that is powering something that is important in someone else's apartment. (A computer with an important paper, life dialer, etc)

(Mod Note: please combine my last two posts, forgot the multi quote.)