Introduction, Difficulty Level and Needed Tools
Light switches of course control power to light fixtures on a straightforward "on and off" basis. However, dimmers vary the amount of voltage or the duration a lamp receives power, thereby varying the light output of the bulb.
Dimmers of old operated using a rheostat which was a large variable resistor. As you increased resistance in the rheostat, voltage to the lamp was decreased and the energy that would have gone to a brighter light wound up as wasted heat energy in the dimmer.
But times have changed and now we use electronic dimmers. Electronic dimmers such as those made by Lutron® and Leviton® use a cool little device called a Triac. A TRIAC is a three terminal, solid state electronic switch or relay that quickly turns power to a lamp on and off up to 120 times per second. Since this power sequencing occurs so fast, it is not perceptible to the naked eye. Other benefits are that it generates very little heat and saves energy. Tricky little Triac!
So read on! This tutorial walks you through the steps of replacing a single pole switch with an electronic dimmer using incandescent or halogen lighting. You can do it easily, create mood lighting and save energy in one easy project.
NOTE: If you have a standard compact fluorescent lamp (CFL) then sorry, that lighting will not work with a dimmer. If you want to dim a CFL you need a special dimmable CFL and they run about $10 to $20 depending on the wattage. Oh, and if you want to use a dimmable CFL, please read the tutorial on 12 steps to clean up a broken CFL bulb.