# Light switch only has 1 white and 1 black wire?



## rjniles

The green screw is for a ground connection if you have it. It can be a bare copper wire, a green wire, a metallic conduit or the metallic sheath of a cable. If you do not have a ground in the switch box, leave the green screw vacant.

Connect the black and white wires to the other screws. It does not matter which is which. Turn the power off to the circuit before you do anything.


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## screwy

You have house that has wiring that has no ground wire. The black is your power and the white is your neutral. The green screw on the switch is it to ground the switch. Your switch is opening and closing the circuit to allow power to your light. You should actually be connecting two black wires to the switch. The correct configuration should be Black(power in) to switch, Black(power to light) to other side of switch. The whites(neutrals) should be connected together. 

Unfortunately the way you explained thing leads me to believe that the above is not what you are dealing with. Just replace the the two wires you took off the old switch and put them on the new switch. Forget about the green screw.

Reply before trying anything out, understand and be careful, please.


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## screwy

rjniles said:


> The green screw is for a ground connection if you have it. It can be a bare copper wire, a green wire, a metallic conduit or the metallic sheath of a cable. If you do not have a ground in the switch box, leave the green screw vacant.
> 
> Connect the black and white wires to the other screws. It does not matter which is which. Turn the power off to the circuit before you do anything.


Yes it does matter, when you go to the light you will have a white wire feeding power, this is dangerous.

Also it matter because on a switch up is on and down is off.


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## brric

screwy said:


> Yes it does matter, when you go to the light you will have a white wire feeding power, this is dangerous.
> 
> Also it matter because on a switch up is on and down is off.


It is a switch loop. The white wire is NOT a neutral.


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## brric

Follow post #2 and you will be fine.


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## rjniles

screwy said:


> Yes it does matter, when you go to the light you will have a white wire feeding power, this is dangerous.
> 
> Also it matter because on a switch up is on and down is off.



Where did you get your wild ideas? He has a switch loop and has no bearing which wire is connected to the switch terminals. There white wire is the one that is hot (or should be) and should be marked black with tape or other means to identify it as a hot lead.

You statement about up and down makes no sense other than the switch should be installed in the box with the on side up.


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## Speedy Petey

screwy said:


> You have house that has wiring that has no ground wire. The black is your power and the white is your neutral. The green screw on the switch is it to ground the switch. Your switch is opening and closing the circuit to allow power to your light. You should actually be connecting two black wires to the switch. The correct configuration should be Black(power in) to switch, Black(power to light) to other side of switch. The whites(neutrals) should be connected together.
> 
> .................
> 
> Yes it does matter, when you go to the light you will have a white wire feeding power, this is dangerous.
> 
> Also it matter because on a switch up is on and down is off.


What is your professional are of expertise? 
From reading these replies it is obviously not electrical.:whistling2:


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## bhennon

rjniles said:


> Where did you get your wild ideas? He has a switch loop and has no bearing which wire is connected to the switch terminals. There white wire is the one that is hot (or should be) and should be marked black with tape or other means to identify it as a hot lead.
> 
> You statement about up and down makes no sense other than the switch should be installed in the box with the on side up.


I agree! Hopefully "screwy" is not an electrician! a switch just opens and closes the circuit. it doesn’t matter which is which....WOW. Also "Screwy" said that you should be connecting two black wires... that is also not necessarily a required scenario so disregard that comment as well. 

One thing i might add is:

You mentioned that this is the last switch in the house. Have the others had a ground wire (plain copper or green)? If so you may want to look a little closer and see if there is a ground within the wiring going to the light that maybe someone cut off since there wasn’t a screw for it, if so, you will want to somehow get that connected to the green screw on the switch.


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## AllanJ

screwy said:


> Unfortunately the way you explained thing leads me to believe that the above is not what you are dealing with. Just replace the the two wires you took off the old switch and put them on the new switch. Forget about the green screw..


When there is just one white wire and just one black wire (altogether) both are to be treated as hot. To be absolutely correct, the white wire in this situation should be the wire that is always hot and the black wire goes to the light and is made hot when the light is turned on (using the switch you are installing this very moment) but once in awhile you find the wires reversed.


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## kango86

Thanks for all the input, for the most part the house was not grounded. As a matter of fact when first moved in I had the house inspected and there were only 3 outlets in the house that were grounded. The electrician has the house grounded now throughout but at first, most was not grounded at all.



> Have the others had a ground wire (plain copper or green)?


Yes, there has been no consistency here and that is not only regarding the electical but that's another issue here and there.



*Ok, here is what done following Step #2*
-Connected the white wire to the top screw on left and the black to the bottom screw and then left the green untouched and all is back to normal and working.

Really appreciate replies and the site itself for being avail as has helped with some other questions as well in other areas.

Thanks again all.


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## lemonhead

*really now....what is the answer*

Well after reading all those replies about some people not knowing this or that I was hoping to get to the solution to the problem first stated.....I too have an old house with just the black and white wire in the bathroom switch that controls the light fixture above the medicine cabinet on the other side of the room......so the switch was bad and I needed to know if the black coated cooper wire or the white coated cooper wire goes on the top screw or bottom screw of the new switch that has the two screws on one side as opposed to the old switch that had one on each side....I do believe this is what the original question was......so.........the answer is the top screw should have the white coated wire and the bottom the black......thank you for your info too bad I had to go through all that other back talking before getting to your solution.:whistling2:


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## Code05

lemonhead said:


> Well after reading all those replies about some people not knowing this or that I was hoping to get to the solution to the problem first stated.....I too have an old house with just the black and white wire in the bathroom switch that controls the light fixture above the medicine cabinet on the other side of the room......so the switch was bad and I needed to know if the black coated cooper wire or the white coated cooper wire goes on the top screw or bottom screw of the new switch that has the two screws on one side as opposed to the old switch that had one on each side....I do believe this is what the original question was......so.........the answer is the top screw should have the white coated wire and the bottom the black......thank you for your info too bad I had to go through all that other back talking before getting to your solution.:whistling2:


It does not matter which wire goes on which terminal, as long as the white wire is remarked as a hot and feeds the switch.

Assuming you know the grounding/green terminal is different.


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## Haligonian

doesn;t matter which screw takes which wire


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## ddawg16

Just to confuse the situation a bit more.....there are two basic ways to wire a light.

1. Run 14-2 from the load center to the light....then run another section of 14-2 from the light to the light switch. At the light, the neutrals get connected and the hot goes down to the light switch. I have always been told to connect black to black at the light...that way the black at the switch is assumed to be hot. The white then gets connectd to the hot side of the light.

2. Run 14-2 to the switch....then another leg up to the light. Neutrals get tied together...hot goes to the switch...black to the light is on the output of the switch....light gets wired to black and white.

I like method 1 because it allows you to install a ceiling fan and have power for the fan indepentant of the light switch. Method 2 turns off both the fan and light.

It really does not matter which gets connected to the light switch....hot or neutral....either one will shock your a$$ if the bulb is installed. If the light has the hot connected and the neutral is open....that neutral has an open circuit volatege of 120v.....

As a general practice, it's best to avoid switching neutrals....that is how people get hurt.


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## Haligonian

ddawg16 said:


> 1. Run 14-2 from the load center to the light....then run another section of 14-2 from the light to the light switch. At the light, the neutrals get connected and the hot goes down to the light switch. I have always been told to connect black to black at the light...that way the black at the switch is assumed to be hot. The white then gets connectd to the hot side of the light.


I was always told the opposite so you don;t have two whites on the light. Guess every electrician has different methods


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## brric

ddawg16 said:


> Just to confuse the situation a bit more.....there are two basic ways to wire a light.
> 
> 1. Run 14-2 from the load center to the light....then run another section of 14-2 from the light to the light switch. At the light, the neutrals get connected and the hot goes down to the light switch. I have always been told to connect black to black at the light...that way the black at the switch is assumed to be hot. The white then gets connectd to the hot side of the light.
> 
> 2. Run 14-2 to the switch....then another leg up to the light. Neutrals get tied together...hot goes to the switch...black to the light is on the output of the switch....light gets wired to black and white.
> 
> I like method 1 because it allows you to install a ceiling fan and have power for the fan indepentant of the light switch. Method 2 turns off both the fan and light.
> 
> It really does not matter which gets connected to the light switch....hot or neutral....either one will shock your a$$ if the bulb is installed. If the light has the hot connected and the neutral is open....that neutral has an open circuit volatege of 120v.....
> 
> As a general practice, it's best to avoid switching neutrals....that is how people get hurt.


 Method 1 is incorrect. The white wire carries power from the ceiling to the switch. Black returns from the switch to the fixture. As to your later comment, the neutral is NEVER put on a switch.


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## rjniles

ddawg16 said:


> J
> 
> I
> 
> It really does not matter which gets connected to the light switch....hot or neutral....either one will shock your a$$ if the bulb is installed. If the light has the hot connected and the neutral is open....that neutral has an open circuit volatege of 120v.....
> 
> As a general practice, it's best to avoid switching neutrals....that is how people get hurt.


It really does matter which gets connected to the switch, it is a code violation to switch the neutral.


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## Jim Port

MitNotrof said:


> I was always told the opposite so you don;t have two whites on the light. Guess every electrician has different methods


Every electrician should not have different methods. Some things like the function of a white in a switch loop is clearly spelled out in 200.7 in the NEC.

Under the 2011 NEC the white will be the neutral in the switch box.


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## Haligonian

Jim Port said:


> Every electrician should not have different methods. Some things like the function of a white in a switch loop is clearly spelled out in 200.7 in the NEC.
> 
> Under the 2011 NEC the white will be the neutral in the switch box.


Didn;t know it was actually code  i've always done it that way, but good to know!!


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## Marbledust

to save wire,the power is run thru the attic from light to light,a short lead from ceiling j box is than run to the switch.one picking up the hot and one to the fixture.the neutrals are in the attic.


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## hayewe farm

Jim Port said:


> Under the 2011 NEC the white will be the neutral in the switch box.


While this is good practice it is not always so, see NEC 404.2(C) exceptions and at thispoint has no bearing on older wired homes.


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## bobelectric

Screwey is screwey... Turn power off,verify power is off,remove existing device, replace with new device as it was wired.replace device ,put on switch cover, ready for testing....


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## CheapCharlie

bobelectric said:


> Screwey is screwey... Turn power off,verify power is off,remove existing device, replace with new device as it was wired.replace device ,put on switch cover, ready for testing....


Exactly. All the other nonsense is not relevant in the OP's question. While background info is good to give, you have to make sure you're giving the right info.

A switch loop is used to feed a switch that has the power from the panel fed to the light first. The white wire to the switch should be connected to the black feed wire in the light j-box. The black from the switch goes to feed the light. The white wire used for the switch loop should be re-identified (black tape) at both ends. Just remember....back on black.

As for the new code (if you care), it requires that a neutral be present in all switch device boxes. This would require running a 3 conductor cable for the switch loop. If you're using a regular switch, the neutral (white) wire is capped off and not used. The red and black wires are used on the switch. Again back on black (don't see any reason to change that). You do not need to re-identify any wires in this case.

Hopefully that helps, just trying to re-iterate the whole thread into one useful post. Bash me if I'm wrong plese.


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## rjniles

CheapCharlie said:


> Hopefully that helps, just trying to re-iterate the whole thread into one useful post. Bash me if I'm wrong plese.




Bash, bash, bash - you spelled please wrong Sorry, the devil made me do it.


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## 428169

Well said, and thank you for clarifying.
bad electrical connections cause house fires, and there is a lot of misinformation in cyberspace.
Prior to 1978, a house in most jurisdictions could be wired any way the electrician wanted to wire it. The Uniform Electrical Code made things not only easier to interpret, but much safer for those who made modifications to an existing circuit.
I know this is a long dead thread, but there are those who will still enter the correct search terms, find this thread, not read though it thoroughly, and create problems for themselves or for their customers.
I'd like to add a slightly more basic understanding of what has been said here:
When only one wire sheath is present in a light switch box, it means that there is no neutral ground in that box. With only 2 wires (and ground, if available) in a switch box, it means that the neutral ground connection has been made elsewhere. It most certainly DOES matter which wire goes to each single pole terminal, as the white wire (while typically referred to as neutral ground) in this instance is usually the "line" (or constant HOT) wire, and the black wire is the "load" (hot once activated, when activating the switch on) wire. This is crucially important, people!
While it really does not matter which wire you use for line and which you use for load (if you are designing a circuit from scratch), if you defy convention, you will confuse future DIYers or electricians, and the prevailing norm is for the white wire (should be always wrapped within an inch of connection with black tape) to serve as the "line" and the black wire to serve as the "load" wire. (Respectfully, if one does not know how to differentiate between the line and the load, he or she has NO business fiddling with electricity.) Many jurisdictions now shun this practice, as they insist on full clarity in wiring, and a neutral ground to be present in every switch and junction box, so check your local codes before attempting the "old school" method of saving wire. However, if one is simply replacing a switch, make sure (assuming you are replacing a switch that worked correctly) you replace the wires that correspond to the terminals you removed them from, and you should be fine. If you are in doubt, consult an electrician! We are far cheaper than the cost of an insurance claim (which may be easily refuted, if the work is considered the culprit to the fire, and your insurance claim adjustor WILL check), and a professional can offer complete peace of mind. If you are hellbemt on making the repairs yourself, use caution, and science:  Do not guess! 





ddawg16 said:


> Just to confuse the situation a bit more.....there are two basic ways to wire a light.
> 
> 1. Run 14-2 from the load center to the light....then run another section of 14-2 from the light to the light switch. At the light, the neutrals get connected and the hot goes down to the light switch. I have always been told to connect black to black at the light...that way the black at the switch is assumed to be hot. The white then gets connectd to the hot side of the light.
> 
> 2. Run 14-2 to the switch....then another leg up to the light. Neutrals get tied together...hot goes to the switch...black to the light is on the output of the switch....light gets wired to black and white.
> 
> I like method 1 because it allows you to install a ceiling fan and have power for the fan indepentant of the light switch. Method 2 turns off both the fan and light.
> 
> It really does not matter which gets connected to the light switch....hot or neutral....either one will shock your a$$ if the bulb is installed. If the light has the hot connected and the neutral is open....that neutral has an open circuit volatege of 120v.....
> 
> As a general practice, it's best to avoid switching neutrals....that is how people get hurt.


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## rjniles

Electrician99 said:


> Well said, and thank you for clarifying.
> bad electrical connections cause house fires, and there is a lot of misinformation in cyberspace.
> Prior to 1978, a house in most jurisdictions could be wired any way the electrician wanted to wire it. The Uniform Electrical Code made things not only easier to interpret, but much safer for those who made modifications to an existing circuit.
> I know this is a long dead thread, but there are those who will still enter the correct search terms, find this thread, not read though it thoroughly, and create problems for themselves or for their customers.
> I'd like to add a slightly more basic understanding of what has been said here:
> When only one wire sheath is present in a light switch box, it means that there is no neutral ground in that box. With only 2 wires (and ground, if available) in a switch box, it means that the neutral ground connection has been made elsewhere. It most certainly DOES matter which wire goes to each single pole terminal, as the white wire (while typically referred to as neutral ground) in this instance is usually the "line" (or constant HOT) wire, and the black wire is the "load" (hot once activated, when activating the switch on) wire. This is crucially important, people!
> While it really does not matter which wire you use for line and which you use for load (if you are designing a circuit from scratch), if you defy convention, you will confuse future DIYers or electricians, and the prevailing norm is for the white wire (should be always wrapped within an inch of connection with black tape) to serve as the "line" and the black wire to serve as the "load" wire. (Respectfully, if one does not know how to differentiate between the line and the load, he or she has NO business fiddling with electricity.) Many jurisdictions now shun this practice, as they insist on full clarity in wiring, and a neutral ground to be present in every switch and junction box, so check your local codes before attempting the "old school" method of saving wire. However, if one is simply replacing a switch, make sure (assuming you are replacing a switch that worked correctly) you replace the wires that correspond to the terminals you removed them from, and you should be fine. If you are in doubt, consult an electrician! We are far cheaper than the cost of an insurance claim (which may be easily refuted, if the work is considered the culprit to the fire, and your insurance claim adjustor WILL check), and a professional can offer complete peace of mind. If you are hellbemt on making the repairs yourself, use caution, and science: Do not guess!


And you dig up a 5 year old post??

Sent from my RCT6203W46 using Tapatalk


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## hkstroud

> cost of an insurance claim (which may be easily refuted, if the work is considered the culprit to the fire, and your insurance claim adjustor WILL check)


Drop the bull crap about insurance, and insurance adjuster checking anything about permits or qualifications. It is simply not true. I can burn my house down through stupidity (electrical or otherwise) and insurance still pays as long as it was not intentional.

I defy anyone to show me any thing in an insurance policy about what a home owner can or cannot do, qualifications or permits

A professional electrician may have some liability for gross negligence but that would almost impossible to prove.

And if you don't believe me ask your insurance agent.


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## harok375

Marbledust said:


> to save wire,the power is run thru the attic from light to light,a short lead from ceiling j box is than run to the switch.one picking up the hot and one to the fixture.the neutrals are in the attic.


 
That's what I figured, that the neutrals had to be "hidden" somewhere.

Added a second vanity light, and corresponding larger box/another switch. Existing switch had white wire (with black tape on it, signifying it was a hot lead) connected to the bottom of the switch, with the black connected to the top.

A continuity tester showed that the white wire at the light wasn't the same white wire at the switch. Knew it had to be a neutral white at the light but had no idea where it was!

Simple to fix, just ran the white wire over to the second light so it would have neutral. Ran 14/2 from the light to the new second switch. Ran a "jumper" from the white wire on the original switch (which had black tape, signifying it was a hot lead) to the bottom of new switch, supplying a hot. Connected the black wire from new switch to black lead on light.

Anyone see any issues?


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## harok375

rjniles said:


> And you dig up a 5 year old post??
> 
> Sent from my RCT6203W46 using Tapatalk


 
Google did just that for me....


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