wall switch has two black, but no white wires

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Old 07-11-09, 11:54 AM
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wall switch has two black, but no white wires

we are replacing a cieling fan. the new cieling fan has its own wall switch, and the new wall switch has two black and one green wires. the black wires are labeled and indicate that they are NOT to be connected to white wires.

The diagram that came with the device shows two dotted but separate black wires connected to the switch...one going to the 120v power and one connected to the cieling fan.

the question is...can we connect both black wires to the existing black wire in the wall, or do we have to do some rewireing?
 
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Old 07-11-09, 12:09 PM
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You should either have two black (or some other colors other than white/green/bare) wires in your existing box.

Or, if you have a switch loop you will have one black wire and one white wire and a bare ground. The code now is to color the white black to indicate that it is a hot wire but it is not always done (or not required at the time your place was built). If your existing switch was connected to the black and white wires in the switch box disregard the colors and connect the new switch the same way as the old.
 
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Old 07-11-09, 12:12 PM
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Originally Posted by 123Bland View Post
we are replacing a cieling fan. the new cieling fan has its own wall switch, and the new wall switch has two black and one green wires. the black wires are labeled and indicate that they are NOT to be connected to white wires.

The diagram that came with the device shows two dotted but separate black wires connected to the switch...one going to the 120v power and one connected to the cieling fan.

the question is...can we connect both black wires to the existing black wire in the wall, or do we have to do some rewireing?
What color wires are on the existing wall switch?

How many cables (jackets with multiple wires inside) come into the switch box? Ceiling box?

Is there currently one switch that controls both the light and the fan, or two switches so they can be controlled separately?
 
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Old 07-11-09, 12:13 PM
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can we connect both black wires to the existing black wire in the wall,
Yes. The white wire on the current switch should have been painted black but often that doesn't get done. The switch instructions were referring to a neutral wire. The white wire on the current switch is not a neutral.
 
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Old 07-11-09, 12:50 PM
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Originally Posted by ArgMeMatey View Post
What color wires are on the existing wall switch?

How many cables (jackets with multiple wires inside) come into the switch box? Ceiling box?

Is there currently one switch that controls both the light and the fan, or two switches so they can be controlled separately?
The ORIGINAL light switch had one white, one black and one green connected. It was a standard switch you can buy anywhere...not old.

The NEW switch has two black wires, and a green
1. BLACK TO POWER SUPPLY
2. BLACK TO FAN
3. GREEN

both black wires also say: do not connect to neutral.

I ASSUME that i should connect #1 on the switch to the BLACK coming out of the wall, and the #2 to the WHITE wire.
 
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Old 07-11-09, 01:36 PM
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The white wire that should have been re-identified would be the power in. The black wire would be the switched hot going to the fan.
 
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Old 07-11-09, 02:44 PM
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Originally Posted by 123Bland View Post
I ASSUME that i should connect #1 on the switch to the BLACK coming out of the wall, and the #2 to the WHITE wire.
In most cases the white wire of a switch loop will be the hot wire and the black will be the switch leg

With most single pole switches is shouldn't matter which is connect to the hot but I suggest connecting the white to #1 and the black to #2. .
 
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Old 07-12-09, 08:56 AM
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Originally Posted by pcboss View Post
The white wire that should have been re-identified would be the power in. The black wire would be the switched hot going to the fan.
Originally Posted by Tolyn Ironhand View Post
In most cases the white wire of a switch loop will be the hot wire and the black will be the switch leg.
Not to hijack the thread, but why is this? It would seem to be more consistent to use black in the switch loop as power in since it's always hot and white (re-identified with black marker or tape) as switched hot.

It doesn't really matter - just curious.
 
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Old 07-12-09, 09:08 AM
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Originally Posted by ByteWrangler View Post
Not to hijack the thread, but why is this? It would seem to be more consistent to use black in the switch loop as power in since it's always hot and white (re-identified with black marker or tape) as switched hot.

It doesn't really matter - just curious.
Allright you asked for it .,

Here from the Electrician's answer { few of us here are electrician }

The reason why we remarked white cable as hot on switch loop { it dont matter if single pole or three way switch loop } due incomming power always be hot with remarked white once you leave the switch it will be black switched conductor.
Yes it is allready mention in the NEC code.

And with switch loop with remarked white conductor tied to live conductor that will give us quick indentiftion that is a switch loop format.

The other reason why we done that for long time when someone else want to change the ceiling luminaire { wall of course also } they can able get correct connection without getting confused how it should be hook up properly.

It is written in the NEC code for last 15 or so years maybe longer but for last couple cycles it really enforce it more clear on that and that is part good for NM/ UF cable but indivual conductor to the switch box is no-no.

Kinda off topic a little but it is related to here reguarding remarking on larger conductors once you get over #6 (16mm˛) or larger it is legit to remarked with proper marking due majorty of very large conductor are only in black colour but now they are getting in varius colours the same as smaller conductor { it may raise the price a little and not all area may have that in stock }

Merci,Marc
 
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Old 07-12-09, 09:10 AM
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Originally Posted by ByteWrangler View Post
Not to hijack the thread, but why is this? It would seem to be more consistent to use black in the switch loop as power in since it's always hot and white (re-identified with black marker or tape) as switched hot.
Because that leaves a "true" black wire a t the load connections. Once the switch is in it is not as likely to be changed but lights are. That leaves a "real;" black wire for the light which may occasionally changed by novices. Or that is my guess and I'm sticking to it.
 
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Old 07-12-09, 09:43 AM
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All good points about reidentification of the white wire so I will toss in another:

The Code very specifically states you may not switch a neutral, which is the white wire. We electricians maybe taking it a little far, but to keep things consistent we make the reidentified white wire the hot. Therefore, it is not switched.
 
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Old 07-13-09, 03:16 PM
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Thanks for the explanations, guys.

Carry on! Beer 4U2
 
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