A dimmer is a device for varying the light intensity emitted by a lamp. To achieve this result, the most conventional method is to cut a portion of the sinusoid upstream of the controlled device. Over half a period (10ms in 50 Hz), nothing will be sent at the beginning, then after a longer or shorter time (0 - 10ms), the device will let the current flow. By adjusting the ratio between the part or the device is blocking, and the one where it is passing, one adjusts the amount of energy sent downstream.
This type of mechanism works well with incandescent bulbs whose behavior is similar to that of resistance. On the other hand, with LED laps or laps comprising a ballast such as compact fluorescents, this poses a problem. Some of these lamps have been specially designed to support a variable intensity, they are often referred to as "dimmable" because in English, a dimmer is called a "dimmer". Before you start replacing a switch with a dimmer, you must ensure that the associated lamp supports variations.
Difficulty level: Easy.
Phillips screwdriver and / or flat depending on the material
Multimeter (optional but highly recommended)
Before installing your drive, first turn off the power at the main switchboard and check if there is no voltage at the multimeter. Then dismount the switch you wish to replace by the drive and note the existing connections to be able to go back if the need arises. Two wires must be connected to the switch: one from the electrical panel, and the other going to the bulb.
Disassemble the switch and examine the condition of the conductors. If they show signs of mechanical crushing, which is common with screw switches, it will cut the damaged part and strip a new healthy portion of the cable.
Once the cables have been prepared, all that remains is to connect the two conductors to the terminals of the drive, and to reassemble the drive in place of the switch. Once this step is complete, you can turn the power back on, and test your new installation.
Note: The installation of a dimmer can only be done in the place of a simple switch, it can not replace a switch mounted in a back and forth, or a pusher connected to a remote control switch. If you are in a similar case, all-in-one solutions exist at some manufacturers. You will then need to replace the first switch by the control module, and the second with a push button.