Switching back and forth: Switching 
or more lighting points from two different locations.
The principle of the mechanism is based on the permutation of a contact. This contact directs the voltage to two terminals. One of these two terminals depending on the position is on or off. This is the principle of the coming and going.
Light control devices shall be fixed at least approximately 1.10 m from the finished floor. This is approximately the height of the door handles. The control box should be positioned opposite the door hinges.
For the realization, it is necessary to define the places of installation wisely. There are two sorts of pose: apparent, also said protruding and recessed. If the choice is made for the protruding method, the conductors will be in tubes or moldings. In the case of recessed installation, the ducts are sealed in the walls or partitions.
For the realization of the electrical wiring, one must think first of the safety. All connections must be switched off, the main circuit breaker switched off!
Electrical installation good
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