Power to a double switch

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Lee Polowczuk

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I know i will get it....

if you guys were here..it would probably take 2 minutes to figure out.

I'll keep you posted..and try not to bug you any more
 

JWelectric

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Take a minute and explain just what you have.

Start with where the power is coming into and go from there.

Ie;
Is the power coming into the same box with the switch or is it coming in the box with the light?

Are both fan and light coming into the switch or are they going to a different junction box?


Start with where the power is coming into and go to each point that you are wanting to control telling the type of cable you have installed.
 

Lee Polowczuk

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Here is the way I understand it.

The old fan worked fine, i just wanted to replace it because it was noisy.

At the same time, i wanted to add a new light during my bath remodel. So I wanted to put two "appliances" on a single gang double switch.

The fan had to have power somehow... so i looked up in the ceiling and there was a junction box there. It fed the fan in one direction, (which i tied black white stripe to black and white to white) and a separate wire from the junction box ran down the wall to the wall switch.

That wire had a white and a black/white stripe (it is not modern day romex, so no ground).

Hooked it up and it worked. Essentially a plug and play replacement

i then ran romex from the new light down the wall. So i have yellow romex with a white, black , and ground. I need to get power to that light and to the wall switch.

it seems like there should be an easy way to tie the fan power to the switch, and then the switch to the light.

You guys are way too patient. My neighbor has promised to help me, but I want to learn and understand the concepts..thus my fight onward.

i have the ceiling buttoned up. However the wall is open and i can see another romex that can be tapped into if necessary. it feeds another wall switch (a three way) for purposes of this argument this paragraph should probably be deleted to avoid confusion
 

JWelectric

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lee polowczuk said:
The fan had to have power somehow... so i looked up in the ceiling and there was a junction box there. It fed the fan in one direction, (which i tied black white stripe to black and white to white) and a separate wire from the junction box ran down the wall to the wall switch.

That wire had a white and a black/white stripe (it is not modern day romex, so no ground).

Hooked it up and it worked. Essentially a plug and play replacement

In the junction box you have the supply from the panel. The white from the supply in this junction box is connected to the white that goes to the fan. The black from the supply is connected to one of the conductors going to the switch and the other conductor from the switch is connected to the black going to the fan.

Does this sound right?

If I am right then the two conductor coming from the junction box to the switch will need to be replaces with a three conductor in order to get the two lights to work from the stacked switch and the two conductor cable from the new light needs to go to the junction box.

lee polowczuk said:
i then ran romex from the new light down the wall. So i have yellow romex with a white, black , and ground. I need to get power to that light and to the wall switch.

it seems like there should be an easy way to tie the fan power to the switch, and then the switch to the light.

Here is where you are going wrong. If there is only two conductors coming from the junction box to the switch then the switch does not have the grounded (neutral) conductor that would be required for the light to operate. The cable for the light MUST go to the junction box in order to tie into the grounded (neutral) conductor there.

The switch would then need three conductors as follows, one to supply current to the switch and one conductor for the fan and another to supply the light.

Think of this circuit like this; current is supplied from the black wire and MUST return through the white wire. The supply (black) wire and the return (white) wire from the panel is in the junction box. As it was originally installed the current came into the junction box down to the switch back to the junction box to the fan returning on the white wire to the junction box and then to the panel.
To add another fixture to this circuit we MUST have the return (white) path and a supply (black or any other color) for the new fixture.
From the junction box we connect both the fan and light return (white) wires to the return (white) wire going back to the panel. Then send the current down to the stacked (two) switches (if using three conductor NM cable the white conductor with a color tape at each end to reidentify it as other than white) wire through each switch back to the junction box through the black and red wire to the fan and light by way of the black wire to each.

Now we have current coming into the junction box going down to the switch and back to the fan (black) and the new light (red) through each back to the junction box through the white where they both can return on the white in the supply.
 

Lee Polowczuk

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In the junction box you have the supply from the panel. The white from the supply in this junction box is connected to the white that goes to the fan. The black from the supply is connected to one of the conductors going to the switch and the other conductor from the switch is connected to the black going to the fan.

Does this sound right?

Yes, this sounds right

If I am right then the two conductor coming from the junction box to the switch will need to be replaces with a three conductor in order to get the two lights to work from the stacked switch and the two conductor cable from the new light needs to go to the junction box.

I am beginning to understand... but the junction box could now be a PIA to get to...

I will have to think this through a bit....

You guys are worth your weight in gold.. i can do plumbing and auto mechanics (non electrical), but electricity really throws me.

i am also wiring for a whirlpool tub and heater...but those on are dedicated GFCI circuits..and i will have an electrician (i always planned for this) hook it up to the basement panel..

i'll keep you posted on the eventual solution.
 

Mikey

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Bottom line is you've got to understand the notion of a "circuit". There's a reason that a battery has two contacts on it, a receptacle has two outlet holes (plus the 3rd -- a ground -- which we can ignore for this discussion), and two wires come from the panel. In all these cases, one wire (the "hot" wire) can be thought of as the source of the electricity, but you can't actually "use" electricity without returning the "used" electricity to the other contact, wire, hole, etc.

The way you've wired the light, if I understand it, is you've got two wires going to it, but both of these wires come from the source -- ultimately the black wire from the panel. One side of the light has to be connected to the return side -- the white wire from the panel.

Moral: never close up your work until it works.
 

Jadnashua

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Let me try again.

WIth the cable that comes from the power panel, when it gets into the box where the fan is now do this:
- add a new 2-wire cable: connect it to the incoming wire from the panel: black to black, white to white, and connect the ground wire (since you don't have one coming from the panel) to the box.
- run this wire to the new light fixture's box.
- connect the white wire to the light's white wire, and the ground to the box.
- take the wire you ran to the switch, and connect it's white wire to the black on the lamp and the black to the black of the two cables.

Mentally, now, follow the power - from the power panel the hot wire gets jumpered and runs down to your new switch. WHen you close the switch, it runs back up to the hot side of the lamp (it's black wire). Through the lamp, to the white wire that goes back to the power panel through the jumpers between the two boxes.
 

JWelectric

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lee polowczuk said:
I am beginning to understand... but the junction box could now be a PIA to get to...

All juction boxes are required to be;
Accessible (as applied to wiring methods). Capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish of the building.
 

Mikey

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I suspect that even though the box is "accessible" as required, it now ain't so easy to get another wire into as it used to be. Lee, welcome to the wild and wonderful world of wire-fishing! All you've really got to do is get a single wire from the fan, to either the switch or the light -- child's play.
 

Frenchie

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Mike - you keep forgetting that I always take your side on those debates. Read Verdeboy's thread.


Lee - keep bugging us. It's when you don't ask more questions, that I get nervous.

(did he misunderstand? Is the reason we haven't heard from him, that he's getting electrocuted?)



If it helps - this is wildly innacurate, but works for me - I picture electricity as a closed water system, like a hydronic heating system.

The switches are valves. Any load (the fan, the light, etc) is a little water wheel that turns when the water runs through.

The main panel is a pump, it only circulates water through the lines. Every circuit must return to the source if it's going to work.

Any dead ends, water can't move.

Black wire (before the load) is under positive pressure, getting pushed by the pump; white wire is under negative pressure, getting sucked by the pump.

Like I said, it's wildly innacurate, but it helps clarify these kinds of problems.

The light/switch circuit has a pipe coming into it, supplying pressure; but it only loops back on itself, there's no return line back to the pump. The whole circuit is basically a dead end.

You need to add a line going back to the source.

Hope it helps, rather than confusing you worse.



If that doesn't, check this drawing:
 

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Lee Polowczuk

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frenchie... that's the best picture yet.... and great explanation, too..

I does seem like the single wire has to go back to the fan, since it has the power source.
fishing a single wire shouldn't be too difficult.. the bathroom is only 6 feet wide and the fan is centered in the ceiling... the wall for the most part is opened up.

Monday, Tuesday, and Friday are my busy days at the day job..

also, my son's car was running hot... and he needs a new fan clutch... now basic mechanics i understand.

i am monitoring the boards and really appreciate you guys.

i promise i'll keep you posted of my progress
 
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Lee Polowczuk

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Success!

My next door neighbor came over today.

Rather than fishing a wire through the ceiling... he took another approach.

This switch was in a double box with another switch... he ran power from there and tied everything together... did the neutral...and ground.

it all works great.

He does suggest that i get a deeper double box. all of the wires are pretty crammed in there..

the older wire (pre-romex) takes up a lot of space.

it is amazing to see someone draw it out on paper and execute.

i finally did understand what everyone was saying... i just couldn't execute.

thanks everyone...

i have to wire two separate gfci connections for the hot tub... but i will have the electrician hook them up to the box.

lee
 

Lee Polowczuk

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I am sorry, man... i just didn't even think that you could tie in that way...

a lot of things make much more sense now... a strong lesson learned.

and i do really appreciate everyone's effort
 
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