Electrical Engineer to Install Ceiling Light/Fan


Old 08-06-06, 07:04 AM
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Join Date: Mar 2006
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Electrical Engineer to Install Ceiling Light/Fan

I am going to break the cardinal rule and install a ceiling light/fan as an Electrical Engineer, although I have been told an electrician would not trust an Electrical Engineer to install a light bulb. I am in debt and have called the electrician out twice already for this job and still don't have my ceiling light/fan installed; no fault of the electrician since my wife moved some parts out of sight.

I have the fan assembled and ready to mount. I have two green chassis wires emanating from the fan, one from the bracket and one from the metal base of the down rod that supports the ceiling light/fan.

I bought a new multimeter since my last one was lost or stolen. I'll make sure power is off. Then I will locate my green wire from light outlet and connect it to two green wires in ceiling light/fan using wire nut. I will then connect white to white and black to black from ceiling light/fan to light outlet. That leaves one black wire unconnected from light outlet which I will assume by-passes everything and goes to other circuits and devices. Note there are two black wires running through the house as part of a two wire single phase system and electrician told my my ceiling light/fan is the central nerve system of the living room and maybe other rooms, by which many outlets, etc. will not work until ceiling light/fan is connected.

I got another ceiling light/fan I may install if I can locate a cover plate for it. This one has two black wires that I have been told uses one black for the light and one black for the fan. I am going to connect both blacks from the fan to one black from the ceiling light/fan outlet using a wire nut and then connnect white to white and green to green as dicussed earlier.

Don't want to burn house down, or cause electrical shock hazard, or destroy electrical system of house, so sure appreciate a response. Don't have the money for electrician.-I am in too much debt and he may charge me another service charge just to tell me there is another reason he can not install my ceiling light/fan. It's time to learn how to do some jobs myself. I know how to trouble shoot houses for shorts and opens, so I am well read on the subject, but have little experience working with my hands, except for replacing a light switch.

Thanks for any help-desperate.
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Old 08-06-06, 07:16 AM
Join Date: Apr 2006
Location: New Bern, NC
Posts: 1,623
If your light box is the nerve center as you say then you have there a feed in, one or more feed outs and a switch loop.

Check out the switch and see if a white wire is tied to one of the switch terminals. If so you need to find that wire at the light box.

Post back and we can go from there.
Old 08-07-06, 04:00 PM
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Ceiling light/fan

There is a white wire and a black wire tied to the two terminals on the switch.

All switch legs have a white and black don't they?

It is just the hot that is switched and colored white on the approach and black on the return.

How does this fact that there is a white provide information related to the central nerve feed for the living room electrical system?

Maybe you are expecting not to see a white wire??
Old 08-09-06, 05:47 PM
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Lighting Outlet Box

The lighting outlet box is configured as such:

There are there are two sets of white, black and ground comming in to the lighting outlet box and one set of white, black and ground leaving lighting outlet box, each in a different conduit while the grounds are bare copper wire twisted and atached to a screw in lighting outlet box.

The electrician left me a black and white wire hangind down. I connected my ceiling light/fan's white to white and black to black. I connected the two greens together on the ceiling light/fan since one of these greens is connected to down rod on the celing light/fan whch is grounded to lighting outlet box through the mounting bracket.

I am curious that one of the white wires comming in to the lighting outlet box is dead ended in to a wiring nut with a black comming in and a black wire going out (a black travelor) as seen from the wire nut. It could be a white switch leg I figure, but makes no sense why there is not white wire leaving the wire nut?
Old 08-09-06, 06:00 PM
Join Date: Sep 2003
Location: Central New York State
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A switch loop using NM or UF type wire (ie using a cable assembly) uses the white to carry unswitched power to the switch and uses the black to carry switched power back to the load.

In your case one of the black wires brings power into the box, the other black wire carries power somewhere else on the circuit and the white wire carries power to the switch.

The term "traveler" does not apply to a circuit where no three or four way switches exist.

Please buy and read a good book on home wiring. It's not difficult. Your present use of terminology and limited knowledge is giving electrical engineers a bad name.
Old 08-09-06, 06:27 PM
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Have you checked to make sure that your box is "rated for fan support"?

If not it should be replaced with one that is.
Old 08-09-06, 08:22 PM
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Join Date: Jul 2006
Location: Mid TN
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Coming from an electrician standpoint I didn't know electrical engineers had a good name..ha ha

As for the problm at hand...ok (the original elctrician) wired the hopuse so a "constant hot" goes into the fan/ceiling box. and THEN goes to the switch. this is known as a "switch loop" what happens is the hot comes into the box and that is where the neutral stops off and goes into the fixture. The hot is then "broken" by the other 2-wire. The hot attaches to the white going to the switch and then (through the switch) comes back on the black wire. Hence the common phrase "down on white back on black". What this mean for you...The neutral (white) from your hot feed goes to the neutral (white) on the fan. The black from the hot feed will attach to the "white" wire going TO the switch. And the black wire FROM the switch will attach to the black wires from the fan.

Hope this helps...I would reccomend getting a basic wiring book or manual. Not only will this save you time, money, frustration and possible injury. But it will also give credence to the opinion that Electrical engineers can learn....

Old 08-09-06, 10:12 PM
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Join Date: Mar 2006
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One Up

I've been one up on you fellas, but two steps back. By George I got it. I have been reading a house wiring book all along so did not need that suggestion, but have not been able to understand it after looking at how the wires are comming in to and out of my lighting outlet box. I do understand it now with your all help.

After talking with you guys the wiring outlet box matches my wiring book exactly, but I did not configure this out until I noticed how the black wire is spliced and then keeps going to the next outlet and then it all hit me like a ton of bricks-bazooka.

Lets wire that ceiling light/fan now and thanks.

From a redeemed EE with masters in EE and 4 years active experience in power EE. 15 years telecom and nuclear/conventional weapons before that-electronics you could say.

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