To replace a pull chain switch, first turn off the circuit break to the pull chain fixture that is currently connected. Next, connect the white wires of the pull switch and replacement wiring and repeat this step with the black wires. Attach the ground wire to the metal mounting plate of the pull switch then mount the pull chain switch into the electrical box in the replacement wiring.
Pull chain switches are commonly integrated into ceiling light fixtures. In this way, no wall switch connected to the light is needed in order to turn the ceiling light off and on. Pulling too hard on the cord can snap the chain or completely pull it out of the fixture, or the internal switch mechanism can wear out. With some models the cord can be reattached, but with other models the entire switch needs to be replaced if the pull chain that operates the ceiling fan or light is accidentally pulled out.
Pull chain fixtures are made from either porcelain or plastic, but porcelain is recommended because it lasts longer and withstands heat better. When mounting porcelain pull chain fixtures, remember that tightening the screws too tight may crack the porcelain shroud.