OK, so you went to Home Depot and picked up a nice new ceiling light fixture. This could be a chandelier, a ceiling fan, a flush mount, a semi-flush mount, or even a sconce. You turned off the power (you did turn off the power, right?) and delicately removed your crummy old fixture. Let’s see here, there are now 3 wires coming from a box (some homes may only have 2 if your wiring is in metal conduit).
Let’s look at the green or bare copper wire first. That is your equipment ground. This wire assures you will not be shocked by a potentially live piece of equipment. You will need the proper tools and trade knowledge to be sure that the ground wire is properly installed as a part of your electrical system. Next, the black wire. Don’t be surprised if you don’t have a black wire, this may be red, or another color – as long as its not white, grey or green, it’s the power wire. The power wire is your ready source of electricity for the fixture. You must understand the power available on that wire circuit and it’s over-current protection capacity, as well as isolated as single circuit source of power. Finally, the white wire. This wire is your grounded conductor. Proper termination of this wire is essential to your home system. This balances the alternating electrical current used by the fixture and supplied by your home electrical service via the black wire.
Let’s cover a few basics about these wires. Let’s first make sure the equipment ground is properly installed. Follow the instructions provided with your new fixture which explains where to connect the equipment ground. Next, you attach the white wire to the corresponding nuetral on the new fixture. Finally connect the power wire to the red or black wire provided with the new fixture, and always be sure to properly use correctly sized wire nuts.
Please keep in mind that the 3 wires coming out of your ceiling have a source, and possibly a further destination if it’s a branch circuit. If you feel comfortable working with electricity, changing a light fixture is certainly a project a homeowner may accomplish. Please remember safety is more important than the cost of your fixture, your existing home electric, and any future demands you may put on your home electrical system. If you’re uncertain of any facet of the project, please don’t hesitate to contact a licensed and insured electrician for their expertise on the matter.