I have an antique home and I am trying to install a new ceilimg fan. The box only has a black and a white wire from the ceiling. I know where to connect the ceiling fan colored wires to - but to which do I put the ground to ?? Do I attach it to the black wire or the white wire??
The Black wire is your HOT line bringing voltage to your fan, and the White wire is the NEUTRAL, or return line. Don't hook the green ground to either! As someone else said, a ceiling fan is in a position that the lack of a ground shouldn't really harm you, but if there is a reasonably easy way to get to a ground (like a water pipe), I'd run a green or bare wire to it from the fan. If you don't run a ground, be sure that you have an insulated switch that you pull to turn it on. Usually there is a metal link chain coming out of the switch. If you run no ground, be sure you use the string that likely also came with the fan and pull thatthus insuring you NEVER come into contact with anything metal where there could be (remote) a risk of shock.
Back in the day it was common to attach a separate ground wire to the metal boxes. They would then run this ground wire to a cold water pipe or chain all the boxes together and run the wire to a ground rod. If your house has armored cable then the steel armour acts as the ground. It is also possible that the box is not grounded to anything at all. The likelihood of somebody getting a shock from touching a ceiling fan is very low since the fan is on the ceiling and people are on the floor. Just connect the ground wire to the metal box. Whatever you do don't connect it to the white or black wires. The only place the white wire should be connected to the ground is at the service entrance.
You do not have anything to connect to the ground. You absolutely should not connect either the black or white wires to the ground terminal. Certainly not the black, ideally neither. The fan will function fine. The ground wire is a safety feature only. Because of the location of the fan, not having a ground connection should not cause any personal danger. Installing without the ground in this circumstance is allowed under National Electric Code.
If there is not a corosponding ground wiring from the box, do not connect the ground from the fan to either wire. However, there might be a ground screw in the box that you could connect the fan ground to.
Connect the ground to the box. Do not attach it to the white or black. If the fan is over a conductive floor I would be sure the fan is grounded. If over a wooden or carpet floor, it is not such a big deal. But per code, all metal parts must be bonded to ground. That is to save your life in case of a problem. If no ground is available you can feed it from a GFI protected circuit to meet code and be safe.
