I have a ceiling fixture outlet which has 4 wires coming out (red, black, white and uninsulated ground). There is only one light switch that controls it. I wanted to attach a light fixture to connect to that, but the light fixture only has 3 wires (red, white and green - ground). How do I connect this light fixture to the 4 wires?
The box in the ceiling was wired in anticipation that someone might want to install a ceiling fan instead of just a light fixture. You need to use a circuit tester to determine if the red or black wire is the one that is controlled by the switch. If you don't have one then remove the screws from the switch, pull it out until you can see the wires that are attached. There should be a black wire on the lower terminal ( power coming in ) then either a black or red attached to the upper terminal. Which ever color is attached to the upper terminal would be the corresponding wire to use in the ceiling box for a light.
U.S. house? Recent (last 50 years) construction? Not knowing how the box was wired originally presents a problem, but only a small one. Green wire ground to uninsulated ground. White wire to white wire (neutral). You'll have to guess whether to use the red or the black wire from the box to connect to the black wire from the fixture. So, take a guess, and cap the other one with a wire nut. If you're wrong, try it the other way. Just be sure to turn the circuit breaker off before wiring, or re-wiring. Or, while the power is off, inspect how the switchbox is wired. Maybe you'll see that the red wire is capped in the switchbox; suggesting that you should use the black wire. Or (more likely) the red wire is switched, and the black wire is always hot. (This would be useful if the box were pre-installed for a ceiling fan.)
Without seeing the ceiling fixture box and wiring myself, i might be hesitant to propose you as to what the extra wires are for. I count on that you mean the field on the ceiling has these wires in them, no longer the ceiling fixture that you simply purchased, seeing that that may have had a wiring diagram that explains what the wires would be for. If I had to bet, i'd say that the field includes three wires due to the fact that it is going to have had a ceiling fan that operated on a different swap than the light, or perhaps the light may also be managed from two special switches on one of a kind facets of the room, or might be both of these. Do you will have an AC voltage tester to see which wires are scorching (are living) and which are not? I hate to propose this, however by and large your great guess is to comply with the wires back to their source to look what they are for. Do you will have a false ceiling that you could open up? Do the wires go into the attic or crawlspace where you could seem at them while not having to tear open the gypsum board or plaster ceiling? You could just put all of the whites together and all the blacks collectively, and make sure the grounds are in position, hoping they've a motive. However now not understanding what they are there for is a good way to intent an electrical fireplace. And i am sure doing that might now not be accredited with the aid of your regional electrical building codes.
Canada and the USA Usually the Red wire in the cieling outlet is controlled by the switch. The Black wire in the cieling outlet should be live all the time. Cap the black wire off with the proper size wire nut. The white wire in the cieling outlet is the common wire. The bare wire in the cieling outlet is the ground wire. it should be attached directly to the metal ground screw in the outlet. The green wire on the light fixture must be connected to the ground screw in the cieling outlet. Connect the white wire on the light fixture to the white wire in the cieling outlet Connect the red wire on the light fixture to the red wire in the cieling outlet. If this does not work, whoever did the wiring did not follow convention. Interchange the red and black cieling outlet wires: Connect the red wire on the light fixture to the black wire in the cieling outlet. Cap off the red wire in the cieling outlet with the proper sized wire nut.
