2 fixtures 1 dimmer and 1 switch 1 from 1 power in

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  #1  
Old 06-26-05, 06:20 PM
nikto1j
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2 fixtures 1 dimmer and 1 switch 1 from 1 power in

Hi, I have one 3-way dimmer connected to the main lighting fixture and now I'm trying to add a single pole switch to control the recessed lights using one power source.

The original 3-way dimmer for the main fixture works fine. If the main light is off -- the recessed lights are properly controlled by the switch as well.

However if the recessed lights are on and I turn on the main light, the dimmer starts controlling both fixtures:
if the main light goes brighter -- the recessed lights go down
and the other way around.


I'll try to explain the diagram:

All white wires are connected together with a nut

Power in:
black wire with a pigtail is connected to the dimmer and to the switch

From the dimmer:
two remaining connectors run to the main fixture (w/ another 3 way dimmer on the other side of the room, which has the same effect on the recessed lights)

From the switch:
remaining connector runs to the black wire of the recessed fixture.

What is going on? Any ideas on how to correct it?
Thanks in advance!
 
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  #2  
Old 06-27-05, 07:39 AM
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I would be interested in a description of how everything was wired before you started. Specifically, I'd like to know the color of the three wires that were connected to the dimmer. I'd also like to know how many cables came into the box, and how many wires were in each cable.

Tapping power from a box with a 3-way switch rarely works.

You identify one wire as "power in". How do you know that it's power in? Where does it come from?
 
  #3  
Old 06-27-05, 02:47 PM
nikto1j
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Thanks a lot for your reply

I wish I could include the image, but have no clue how to do it.


The first electic box (dimmer #1) has two cables:
cable #1 -- black, white and neutral
cable #2 -- black, white, red and neutral
dimmer #1 -- black, red, blue -- common, neutral

cable #3 (the one I pulled from the recessed lights)
switch

all white wires are connected together with a nut
all neutral wires are connected together as well

from the dimmer #1:
black wire is connected to the black wire from the cable #1
blue wire is connected to the red wire from the cable #2
red wire is connected the black wire from the cable #2

from the switch:
wire #1 is connected to the black wire from the cable #1
wire #2 is connected to the black wire from the cable #3

the secon electric box (dimmer #2) has only one cable comming in
cable -- black, white, red and neutral wires
dimmer #2 -- black, blue, red -- common, neutral

from the dimmer #2
blue wire is connected to the red wire from the cable
red wire is connected to the black wire from the cable
black wire is connected to the white wire from the cable

Note: I can be wrong, but I think that the white wire in the second box is hot

all neutral wires are connected together as well

Power in -- i ment hot wire from the cable #1

Thanks again!!!
 
  #4  
Old 06-27-05, 04:42 PM
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First I should point out that you are using the word "neutral" incorrectly. I believe that everyplace you said "neutral" you are referring to the bare "grounding" wire. This is not a neutral.

Next, I'm not sure why you have two dimmers controlling the main lighting fixture. This is unusual. Normally you just use one 3-way dimmer and one ordinary 3-way switch.

I assume that you have not touched the wiring at the main fixture, and that you have not altered the wiring of either dimmer. Is this correct?

I believe your problem is that cable #1 is not the power in as you have assumed. I believe that cable #1 is a switch loop from the main fixture. To confirm this hypothesis, you will need to examine and report the wiring at the main fixture. Please do so and report back.

Unfortunately, if my hypothesis is correct, then no rewiring of any of these boxes will produce the desired result. However, all is not lost. Once I get the additional information from the main fixture, I'll offer other suggestions.
 
  #5  
Old 06-27-05, 10:25 PM
nikto1j
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By neural I mean the white wire
The ground wire in this cable is a bare one.

In any case, cable #1 brings power to the electric box, BUT
whoever wired that circuit... I assumed that the black wire was the hot one (as it usually is and I didn't even check it... my own stupidity) So, after testing, it came up that the white wire is hot and the black one is neutral.

I installed two dimmers because I like to be able to control my lights from both locations. Lutron sells the package (a master and a slave) w/ the wiring diagram.

Checking the main fixture shouldn't change much. Since the white wire in cable #1 is hot, I should be able to tap into it. I have no time to change the wiring right now, but I'll definitely do it tomorrow. I can only hope that it will do the trick, but wouldn't understand why it would make any difference for a single pole switch... and if not, I'm totally out of ideas.

Thanks for your help.
 
  #6  
Old 06-28-05, 06:40 AM
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cable #1 -- black, white and neutral
This is what confused me. That sounded like three wires.

I didn't not realize that you used the master/slave dimmers. They're okay as is.

If your rewiring doesn't work, then I suggest you fall back to the advice in my previous post. I still think it very likely that you are working with a switch loop. Do you know what a switch loop is?
 
  #7  
Old 06-28-05, 07:57 AM
nikto1j
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nope, i don't know what this loop is. I assume that it's not the main power cable, but the one that is used to connect to the switches.

I just finished rewiring and it didn't do anything. If I have to check my fixture (something I was trying to avoid at any cost, since it is really heavy and was very hard to install) and the main power goes directly to it -- does it mean I have to pull a new cable from it to the electric box for the recessed lights? Pulling cable from any other location would be even more difficult. Ouch... Is there ANY WAY to work with a switch loop? At this point I'm OK if the dimmer controls my recessed lights as well, as long as both lights are controlled in the same direction. However, I still would like to be able to turn the recessed lights OFF if the main light is ON.

Can't thank you enough for your help
 
  #8  
Old 06-28-05, 09:37 AM
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A switch loop means that both the black and white wires are hot, and neither one is a neutral. If wired according to today's code (and not all are), the white wire would be the unswitched hot and the black wire would be the switched hot. The end of the white wire is supposed to be marked black to let you know, but this step is often skipped (regrettably).

The problem is not control, but voltage. If you try to tap a switch loop, you'll end up putting things in series rather than parallel, and they won't get 120 volts. Sometimes we can convert a switch loop to a power feed, but that involves making the previously switched device unswitched. When that device is a receptacle, this is often just fine, but in your case, it would not be practical to make your main light unswitched (unless you added a remote control of some kind to it).

For your new switch and light, you can pull power from any source of continuous power. There are hundreds of such sources in your home. However, code says that some of these (such as circuits serving receptacles in kitchens, bathrooms and laundry areas) cannot be used.
 
  #9  
Old 06-28-05, 09:55 AM
nikto1j
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Originally Posted by John Nelson
A switch loop means that both the black and white wires are hot, and neither one is a neutral.
I checked wires with the lights OFF. The white wire was hot and the black wire didn't give any signal. Do I need to have the main light ON to check if the black wire is hot as well?
 
  #10  
Old 06-28-05, 11:29 AM
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As I said, the black wire is a switched hot. It's not hot unless the switch is on.
 
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