How to Install a Security Light
Security lights are a good way to keep burglars from visiting your home at night. Since thieves prefer to work in the dark, lights that are always on (or turn on automatically when they sense movement or heat) are a smart addition.
There are two types of security lights you might wish to install:
1. Lights with infrared sensors – These respond to heat, and the light will turn on whenever a warm object (i.e. a person or a car) comes into range.
2. Lights with microwave sensors – These send out a high frequency radio wave, and they sense any movement that makes a disturbance in the wave pattern.
Both types of security lights are wired the same as indoor ceiling fixtures or wall fixtures.
Here are some simple steps on how to replace your typical porch light with a security light:
1. Turn off the power at the fuse or circuit panel. (There may be several pairs of wires in the wall box. Some may be wired to different circuits than the fixture you’re working on. To be safe, use a circuit tester or turn off the power to the whole house to make sure there’s no power going to the fixture you’re working on.)
2. Remove the light bulb cover and the bulb from the fixture.
3. Unscrew the nuts or screws holding the fixture base to the wall box.
4. Remove the electrical tape or wire nuts from the wires (black is hot, white is neutral, and green—which is not always present—is ground).
5. Use wire nuts to attach the wires of the new fixture to the matching wires in the electrical box.
6. Position the new base plate and screw the new bolts through it so it attaches to the mounting strap.
7. Screw in the light bulb and, if there is one, replace the bulb cover.
8. Turn on the power!
Note: Many security lights have a sensitivity adjustment, so you may have to tinker a bit to keep your light from flashing on when the wind blows through the tree branches or the neighbor’s cat strolls through your yard in the middle of the night.
Source: Home Improvements for Dummies