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Fans and Outlets help

  1. Jul 9, 2012 #1
    I need some help understanding how a House Fan is wired to 2. Switches and 1. Switch can turn the fan on and off and the other Switch can turn the Light on the fan on and off?

    I am familiar with how the Light at the top of the steps work with 1. Switch at the top of the steps and 1. Switch at the bottum of the steps.

    The 2. Switches are called 3. way Switches and the third wire is the Red Wire and I know how all of this works.

    But when I try to lookup ho the Fan with 2. Switches get wired I can not see it to good.

    Thanks for the help
  2. jcsd
  3. Jul 9, 2012 #2


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    In a nutshell, a three way switch just takes the hot wire and gives you two places to switch it. In between the two switches (three way switches in this case) are two wire paths...typically the red and white wire. When you hit either switch, it simply turns the light off....or the light on. (either the hot wire will be closed...or open)

    As far as the other stuff you mention.....tough to interpret what you are saying. They sound just like simple single pole switches that go to loads that are perhaps wired in parallel. Perhaps your switches are also wired in parallel. But until you define your question more.....
  4. Jul 9, 2012 #3
    Yes I do Understand about 3. way Switches and that the Red wire is the Travler wire.

    But how do you wire the Fan to 2. switches so 1. switch turns the light on and the other switch turns the fan on?
  5. Jul 9, 2012 #4

    jim hardy

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    look carefully at the fan.
    Most i've put up have one wire for the light and another for the motor, both black, and a common return wire that's white. Sometimes the fan is delivered with the two black wires twisted together.
  6. Jul 9, 2012 #5
    Well I am not looking at one here I just wanted to know about the wiring.

    Se if you have a Light and 1. Switch the Switch gets wired in Series with the Light.

    And the Light has one TERM for the Hot wire and One TERM for the White wire.

    But now you have two Switches and the fan has one TERM for Hot and one for White and one more for Hot again.

    If I could just see a photo of what it all looks like wired I could tell you were I am lost?
  7. Jul 9, 2012 #6


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    If I parsed what you wrote properly, the fan motor and the lights are different circuits, controlled by the two switches. Thus, switching the light on and off has no effect on whether or not the fan switches on and off (and vice versa). If turning off the light also turns off the fan, the feed for the fan circuit is fed from the light circuit just after the switch (assuming you're switching hot, and not connecting neutral).
  8. Jul 10, 2012 #7
    I am sorry let me start over.

    I know how a singal Switch is wired to a Selling Light.

    Now Ten years ago I had my Cousin put in a Selling Fan with a Light.
    And I have 2. Switches now one for just the Light on the Fan and one Switch for just the Fan.

    Now I found this photo on the net

    And I am geting lost on how this configuration works. I am just wanting to know.
  9. Jul 10, 2012 #8


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    The picture is a pretty good representation of a standard wiring diagram, so I suspect your problem may be a little more fundamental (nothing wrong with that--we all had to start somewhere!)

    First off, your picture comes originally from this page, which has a basic description:

    The power in (on the bottom left) contains line (or hot), neutral, and ground. In extremely simplified terms (and not completely correct, but good enough for introductory material) you can think of line as the actual 'source' of electricity, neutral as the 'drain' (where the electricity has to flow after it's been 'used up', and ground is required for safety (in the water analogy, think of it as an 'overflow' there to prevent electricity from flowing where it isn't supposed to).

    Line is split to both the dimmer and the fan, the output of the dimmer (the red wire) goes to the light, while the output of the switch goes to the fan via the black wire. The neutral is connected to the other wire of both the fan and the light, forming a return path from source to drain. Ground (the green wire) is usually attached to the electrical box itself, and is used to provide an emergency return path in case something electrified goes loose or breaks (the box is a better return path than, say, a person that happens to touch the light / fan).

    Does that make sense?
  10. Jul 11, 2012 #9
    Ok I know that coming out of the Celling will be 3. wires
    Black Hot
    White Neutral
    Green Ground

    and I know how they will connect to a Light if you have one up.

    Now when you take the Liight Down and go to put up a Celling Fan that has a Light the Celling Fan will have 4. wires
    Black Hot
    White Neutral
    Green Ground

    Now I know White from Fan goes to White from Celling and Green from Fan goes to Green from Celling.

    Now the Black from Fan and Blue from Fan you twist them both togather. Then you connect them to the Black from the Celling.

    This configuration will make the Black Hot from the Celling Fead and controale both the Light on the Fan and the Fan I get all of this.

    And this is if you want to just use the One 2. way switch and again I get all of this.

    But if you connect the Back from the Fan to the Black from the Celling this give power just to the Fan. But if you connect the Blue from the Fan to the Black from the Celling this just gives Power to the Light on the Fan.

    So when you connect both Black from Fan and Blue from Fan to Black from Celling the Black from Celling will Power both Light and Fan I get all of this.

    But wont this be to mutch Power for the Black from the Celling to give?
  11. Jul 11, 2012 #10


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    Hey....I'm just curious. Why do you put a period after every number you use?

    For example "Ok I know that coming out of the Celling will be 3. wires"

    I've never seen that before. What country or language is this used in and why?
  12. Jul 11, 2012 #11


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    Just my two cents...but, If I were going to do this.....and I have done stuff like this before....I simply draw it out in schematic form. In other words, I start with a voltage source and draw all my loads in parallel with all the switches in series or parrallel, whatever the case may be. Draw it in simple single line form first. Once you have the single line schematic, you can then advance the drawing to show all the individual wiring.

    Also, if you drew out what you were describing in schematic form, and posted the schematic on this forum, it would be simple for everyone to understand including yourself. Reading about wiring in paragraph form is always difficult to understand.
  13. Jul 11, 2012 #12


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    Okay, good--we've finally come to the actual source of confusion! As long as the combined current draw of the fan and of the light are less than the current carrying ability of the feeder (the black wire from the ceiling supplying power) it'll be okay, and the feeder can supply both. The rule-of-thumb ampacity (safe current-carrying ability) of 14 gauge cable is 15 A, and if 12 gauge wire is 20 A. Otherwise, you'll need to run a separate feed from your panel.

    As the fan motor is probably <100W (less than an amp), and you probably have no more than 3 or 4 60W bulbs (an amp or two), you're probably well within the carrying capacity of the wiring (unless you're running other significant loads on the line).
  14. Jul 11, 2012 #13
    I am in the USA and I always put a . after a singal number but I know you do not have to.

    And as for 100 Watts being less then one Amp I thought the Amps would be higher then less then an Amp?
  15. Jul 11, 2012 #14


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    Well, the unstated assumption was that the line voltage is between 110 and 240Vac (as most residential voltages happen to be, worldwide). Given that P = I*V (current * voltage), you can see that the current draw of a 100W load would be less than an amp.
  16. Jul 11, 2012 #15
    Hire an electrician to do this for you.
  17. Jul 16, 2012 #16
    Thank you for all your help and I will post my Drawling soon but I think I tell you what I meen.

    When you take the Fan out of the Box it will have 4 wire coming from it.

    Lets start here am I right on this?
  18. Jul 17, 2012 #17
    OK if you want the Celing Fan and Light to go On and Off at the same time you would connect the wires like this.

    The Black wir coming out of your Celling would connect right to the Blue and Back wire coming from your Celling Fan togather.

    And the White wire coming from your Celling would connect right to the wite wire coming from the Fan.

    Here is the video I saw
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