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#356756 - 10/17/11 11:25 AM Electrical wiring question. Woo!
Ken.C Offline
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Registered: 05/03/03
Posts: 18044
Loc: NoVA
So I was looking to install a ceiling fan in one of our rooms. I need to replace the pan, but that's no problem. What is a problem is that the existing pan has two romexes going into it, and they appear to be on different circuits. Worse yet, the neutral from one is tied to the hot on the other. WTF? Anyone have any clue why this might be like this, if it's safe, and how to deal with it?

I'm probably going to call an electrician, but I'm really curious.

Will post picture of wires later.
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#356759 - 10/17/11 11:39 AM Re: Electrical wiring question. Woo! [Re: Ken.C]
BobKay Offline
connoisseur

Registered: 03/23/10
Posts: 3596
Loc: Massachusetts Badlands
Ken, this is just a stab. Unfortunatley, each house is as different as the parade of tradesmen who have been through there.

I don't think it's possible for it to have functioned while connected to two different circuits. If there is no sign of heat damage (blackened parts), then it should be OK. If it were causing a problem, it should constantly trip the breaker.

I see stuff that is totally inexplicable, yet, has been there for 40 years w/o issue. When that's the case, I install the new stuff just the way the old stuff was connected. No one has ever called back or sued me to replace their burned out home.

Do you think it may have ever had two on/off switches in separate locations? If it is a separate circuit, is it dead and out of the system, or still live?
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#356761 - 10/17/11 11:55 AM Re: Electrical wiring question. Woo! [Re: Ken.C]
nickbuol Offline
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Registered: 09/16/04
Posts: 5338
Loc: Marion, IA
Since I've done a few ceiling fan wiring jobs, and am about 800 feet of electrical wiring in my basement finishing project, I can say that to me, it sounds like someone is "hodge podging" the wiring. I've seen it where someone used two 14-2 or 12-2 (2 wires plus 1 ground) wiring "sets" instead of a single 14-3 or 12-3 (3 wires plus 1 ground) wiring sets to run a ceiling fan/light combo where they have separate switches.

That is why I've used SO much electrical wiring and I have about another 200 feet or so to go in the basement (home theater is all that is left) because I want it done right and the cost of using the correct wiring vs. even having to figure out 5 years from now what I wired today to "cut costs" will be worth it. To some people, the cost of the 12-3 or 14-3 wire over 12-2 or 14-2 is too much and they make up electrical wiring as they go.
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#356765 - 10/17/11 12:09 PM Re: Electrical wiring question. Woo! [Re: nickbuol]
BobKay Offline
connoisseur

Registered: 03/23/10
Posts: 3596
Loc: Massachusetts Badlands
Originally Posted By: nickbuol
they make up electrical wiring as they go.


I think that's definitive, Nick. After ripping apart a client's wall for him, I've seen my electrician cry. Then he talks to our client. Then she cries.
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#356767 - 10/17/11 12:18 PM Re: Electrical wiring question. Woo! [Re: BobKay]
Ken.C Offline
shareholder in the making

Registered: 05/03/03
Posts: 18044
Loc: NoVA
Given the amount of non-working 3 way switches in this place, it wouldn't surprise me. It is a small room, and there's currently only one switch in it, but there's also an outlet in the closet in there, and from looking at other houses in the neighborhood, it clearly was once part of the (formerly) L shaped living room.

Now that I think about it, though, I don't remember if I turned the light switch on when I was testing the power (since I was trying to figure out which breaker the damned thing was attached to. Sssssooooo...

Here's what I know, though. With the breakers (light switch?) off, I didn't get voltage on either loose black or white wire, either to each other or to the ground. I did get ~120V on the black/white mix; I think just to ground, but possibly to the other two wires as well. I guess I'll have to check it again.




Edited by Ken.C (10/17/11 12:20 PM)
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#356795 - 10/17/11 02:05 PM Re: Electrical wiring question. Woo! [Re: Ken.C]
solarrdadd Offline
devotee

Registered: 05/04/10
Posts: 310
Loc: Alexandria, VA
Originally Posted By: Ken.C
Given the amount of non-working 3 way switches in this place, it wouldn't surprise me. It is a small room, and there's currently only one switch in it, but there's also an outlet in the closet in there, and from looking at other houses in the neighborhood, it clearly was once part of the (formerly) L shaped living room.

Now that I think about it, though, I don't remember if I turned the light switch on when I was testing the power (since I was trying to figure out which breaker the damned thing was attached to. Sssssooooo...

Here's what I know, though. With the breakers (light switch?) off, I didn't get voltage on either loose black or white wire, either to each other or to the ground. I did get ~120V on the black/white mix; I think just to ground, but possibly to the other two wires as well. I guess I'll have to check it again.



ken, where in VA are you? i'm in alexandria and i'm a licensed master electrician. if your nearby, i can help.

most of the time when you see a white wire attached to a black or red wire it's a switch leg. what is done is the power from the constant hot is sent down to a two wire switch circuit and the power is sent down on the white wire that attaches to the switch as it's source then the other side of the switch (a single pole) has a black wire sending the power (for ON condition) back out to the load. in the box you should have from that two wire (one cable) a black that attaches to your fan light circuit or a light fixture which ever is in the ceiling (doesn't matter) for a fan usually if there is a constant hot in the box the fan motor ataches to it so that you can have a seperate switch to control only the light fixture portion and this way when you turn the light off at nigh from the switch (could be a dimmer switch or a standard single pole on/off) the fan can continue to run undisturbed by turning of the light at the switch or dimming it.


as for three way switches:
the thing to remember is both switches are the same, one common terminal (usually colored darker than the other two) and then there are two travelers. the only terminal that is of real importance is the common (the darker one of the three) on one switch the 120v hot (power) conductor connects to it (the other two terminals get the travelers, doesn't matter which one of the travelers goes to which terminal) the other switch on the common goes the load (what ever you are controlling with the switch which is usually a light fixture or a receptacle with a lamp plugged into it) and then the two travelers from the other switch go on the remaining two terminals.

with both switches completely removed if you have a good ground only one conductor will give an indication of power when using a proper electrical tester to ground (120v should be your reading) that switch is where the power comes in. once you determine that (don't connect anything yet), go to the next switch three way switch circuit and you need an ohm meter and set it to ohms/resistance and make sure you have your lamp turned on with a standard incandescent lamp in it. when reading to ground, you will read a circuit of resistance. to be certain, turn the lamp off (if it's a lamp in a controlled receptacle) or unscrew the bulb if it's in a ceiling fixture and test it again and you should have an open circuit (infinity or no connection(this is NOT TO BE CONFUSED WITH 0/ZERO which means a short circuit!)for your reading) at this switch the conductor you read resistance to ground from the lamp connects to the common terminal of that switch and connect the travelers back to either of the two remaining terminals, makes no difference.

your 3-way switch circuit is now working properly!

hope this helps.
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#356798 - 10/17/11 02:13 PM Re: Electrical wiring question. Woo! [Re: solarrdadd]
tomtuttle Offline
axiomite

Registered: 06/20/03
Posts: 8488
Loc: Tacoma
Epic win by solarrdadd! Great information.
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#356808 - 10/17/11 02:43 PM Re: Electrical wiring question. Woo! [Re: tomtuttle]
Ken.C Offline
shareholder in the making

Registered: 05/03/03
Posts: 18044
Loc: NoVA
I'm going to have to spend some time digesting that one. I'm in Loudoun County, up near the 7. Thank you!
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#356810 - 10/17/11 04:02 PM Re: Electrical wiring question. Woo! [Re: Ken.C]
solarrdadd Offline
devotee

Registered: 05/04/10
Posts: 310
Loc: Alexandria, VA
Originally Posted By: Ken.C
I'm going to have to spend some time digesting that one. I'm in Loudoun County, up near the 7. Thank you!


that's about an hour or so from me. pm me if i can be of help!
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Marantz AV7702MKII pre-amp
Emotiva XPA-5,UPA-2amps,
14 Speakers, All Axiom
Oppo 105D&93

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#356821 - 10/17/11 05:17 PM Re: Electrical wiring question. Woo! [Re: Ken.C]
Ajax Offline
axiomite

Registered: 12/30/03
Posts: 6331
Loc: Cleveland, Ohio
Originally Posted By: Ken.C
I'm going to have to spend some time digesting that one. I'm in Loudoun County, up near the 7. Thank you!
HA! You can always spot a transplanted Californian. In Eastern-speak, that would be "up near route 7," or just plain "7." wink If it were an interstate, it would be "I7", "Interstate 7," or just plain "7" again.
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