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Old 05-24-2010, 07:12 AM   #16
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I would not rerun the power.

Topologically there are two subcircuits, one for the fan light and one for the fan. Each has power going to switch #1, a 14-3 going to switch #2 and providing 3 way travelers, and hot/neutral to the load. This a simple power-switch-switch-load arrangement.

THe only glitch is that the the fan and fan light share a neutral down to the switch box.

So there is the choice, (1) give the fan subcircuit and the light subcircuit each its own neutral accompanying its travelers and connect both 14-3 neutrals to the single neutral going up to the fan unit, or (2) have both subcircuits share the neutral in one of the 14-3's, the other 14-3 carries travelers only.

One has got to fly.

(The can light subcircuit does not have this problem. Incidently (OT) the can lights have a feed from switch box #1 also, which was left unused in all the solutions discussed so far. It is possible to feed the can lights from switch box #1 and leave the 14-2 feed up from switch box #2 unused instead; the 14-3 for the can lights only becomes a switch loop. This will look a little more confusing when drawn together with the fan subcircuits which are not switch loops.)
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Last edited by AllanJ; 05-24-2010 at 07:16 AM.
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Old 05-24-2010, 08:14 AM   #17
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THe only glitch is that the the fan and fan light share a neutral down to the switch box.
Are you saying it is wrong to tie the fan motor and light leads together and connect to the switch loop?

I mean I would think 14/3, if using 14, from switch 1 to switch 2 and 14/2 to the appliance.

By no means a sparky here.
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Old 05-24-2010, 10:46 AM   #18
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It is acceptable to tie the blue and black wires together if you specifically want to control both light and fan with one switch.

The shared neutral coming out of the fan works perfectly well with the blue and black connected to separate switches. Only that the electrical geeks argue for hours on end in a high ceilinged Victorian furnished library over tea about technicalities and legalities some of which I described a little earlier.

You will need a 14-3 between the appliance (the fan) and switch box in order to control fan and fan light separately.
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Stick to your lawn watering schedule until it really starts to pour. After the storm you have only the same number of rest days you always had and then you need to start watering again.

Last edited by AllanJ; 05-24-2010 at 10:51 AM.
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Old 05-24-2010, 11:40 AM   #19
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Originally Posted by mcdonaldb View Post
I'm alittle confused, why wouldn't this be to code?
Code is an attempt to standardize methods! The first reason being safety, the second being ease of working with circuits.
When the next guy comes along, he will be able to quickly grasp how a circuit functions.

In your case, if you ran your 3-14/3 cables through a two foot piece of raceway, you could argue that its in the same raceway.

If you are on good terms with your inspector, he would maybe ignore your transgression. On the other hand, if he wants to demonstrate his authority, he could order you to make a different arrangement.

You could connect all the white's together in box #1 then wire the pot-lights, the fan and the light to their respective neutrals in box #2.
Its about six of one, and half a dozen of the other, its just a matter of satisfying the code wording.
There is no safety concern here, as all the #14 wire is protected by a 15 amp breaker.

In the days of knob and tube neutrals could come from any source and it would be very easy to have 2-15 amp fuses feeding current to a single #14 neutral with nasty results.
To avoid this problem, that's the reason for the rule!
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Old 05-24-2010, 11:47 AM   #20
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Quote:
Originally Posted by AllanJ View Post
I would not rerun the power.

Topologically there are two subcircuits, one for the fan light and one for the fan. Each has power going to switch #1, a 14-3 going to switch #2 and providing 3 way travelers, and hot/neutral to the load. This a simple power-switch-switch-load arrangement.

THe only glitch is that the the fan and fan light share a neutral down to the switch box.

Allan, this is not a glitch! This is the standard way of doing this!

So there is the choice, (1) give the fan subcircuit and the light subcircuit each its own neutral accompanying its travelers and connect both 14-3 neutrals to the single neutral going up to the fan unit, or (2) have both subcircuits share the neutral in one of the 14-3's, the other 14-3 carries travelers only.

One has got to fly.

(The can light subcircuit does not have this problem. Incidently (OT) the can lights have a feed from switch box #1 also, which was left unused in all the solutions discussed so far. It is possible to feed the can lights from switch box #1 and leave the 14-2 feed up from switch box #2 unused instead; the 14-3 for the can lights only becomes a switch loop. This will look a little more confusing when drawn together with the fan subcircuits which are not switch loops.)
There is no problem here, except it doesn't satisfy the wording of the regulation.
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