Dimmers come in different shapes and sizes, but their ratings are typically the same. A standard dimmer is normally rated at 600 watts although you can purchase dimmers rated at 1000 or 1500 watts if needed. The higher the wattage rating the more expensive the dimmer. Dimmers are designed with fins or heat sinks to dissipate the heat generated from varying the voltage to a light fixture. When ganging dimmers together the fins have to be removed to allow for spacing. This removal de-rates the wattage capacity of the dimmer. With both sides of the fins removed on a dimmer the device can go from a 600 watt capacity to 300 watts. The image shows a bank of dimmers that have been ganged together de-rating the wattage capacity of each dimmer. A door has been placed over these dimmers for concealment. These dimmer are running extremely hot when the door is shut causing a potential of overheating. In conclusion, dimmers will get warm to the touch but not hot to the point of burning your hand when touched. Contact your licensed Philadelphia electrician Lauterborn Electric with all of your electrical needs. Click Images to Enlarge.