Fan Hookup Wiring Question


Ceiling Fan has one neutral ( white wire) for both fan and light. Light has blue wire. Fan motor has black wire. Box where fan is being hooked up has lighting circuit for light switch on one circuit from main circuit breaker panel and fan motor feed coming from sub panel on another circuit. Which neutral should be hooked up to fan's white wire?
Thanks
R
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Do both the feed for the fan motor and the feed for the light that is on a seperate panel come into the same box that is going to be the single control box for the fan and the light? A box that has switches for the fan and the light? If so, why the need for seperate circuits? Just feed the fan and the light off one branch circuit and don't use the other circuit.
If the fan control and the light control are in seperate boxes that are physically seperate, then I don't know what you do with the fact that you have two seperate neutrals coming to the fan from two separate branch circuits and only one neutral connection at the fan.
Another option is to wire the fan/light using a remote control, which can also be left in a wall holster. In that case you;d also use only one branch circuit and wire it so the circuit to the fan/remote module is always live.
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snipped-for-privacy@optonline.net wrote:

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Like it or not, I think you should "undo" the previous wiring UNLESS the fan you intend to use can be rewired to separate the motor neutral from the light neutral.
If you just have conventional CBs or fuses, it will work regardless of which neutral you use but the "hot" and the associated neutral are supposed to stay in the same cable.
Indeed, each cable regardless of use should carry ZERO net current. That means the "return" current is the same as the load current. Unless you have some kind of leakage to ground, proper wiring always ensures this will be the case. It's even true with cables that only serve a switch and 3/4 way switch arrangements.
But that's mostly a theoritical concern. What might cause "complicated" problem would be if someone "for safety's sake" replaces on or the other breaker serving your fan with a GFCI breaker. The odds are great that the mixed or combined neutrals on single pole circuits will cause all kinds of false trip problems.
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Agree with all the above and there are no odds about a GFCI breaker tripping under those conditions, unless you mean 100%. If you just used one circuit neutral or the other or combined them, it will trip as soon as the fan or light, whichever is on the GFCI is turned on.
Is there a reasonable way to run a cable from the light switch location to the fan switch location?
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I can see how that would happen. I'm guessing the supply line for the multiple switches is not in the box where he wanted the fan switch.
The simplest solution to correct the problem code-wise would be to use the "new" supply line for both the light and fan. I believe you should have enough 14/3 between the switches to do this. Just cut off the original suply in what ever box it's in after you are done. Plan your new 3 way wiring before starting. Based on what you told us I believe you can move it all to the new circuit without pulling any wre.
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jamesgangnc wrote:

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You really do need to have both loads on the same circuit. Let me suggest that you figure out which box is easier to get the power from and pull a two wire cable from that box to the fan support box. That cable will supply the power for both fan and light. You then rewire the existing switching circuits to make use of the new power source location. If it turns out to be easier you could replace the cable from the fan control point with a three wire cable so that it will bring both switched and constant power to the fan support box. You then wire the three and four way switching circuit to take advantage of the power supply from that new cable. If any of that is unclear then just ask questions. No one was born knowing this stuff and we all had to start someplace. -- Tom Horne
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ROANIN wrote:

Disassemble the fan enough to locate where the light return is joined onto the motor return, separate them there and add another "white" return so that the light and the motor now each have their own return leads.
Jeff
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Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
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jeff_wisnia wrote:

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Good deal.
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