Originally, circuits operated with open switches, which only had an insulated grip and thus did not provide adequate protection against accidental contact. With the invention of the light bulb by Edison and the advent of electric installations , the need arose for a safe switch to use in home appliances.
First, rotary switch developed that minimized the sparks with a spring mechanism and at shoulder height (about 1.50 m) were mounted. For standardization of the electrical installation, the present height of 1.05 m has been proposed. The rotary switches were initially replaced by toggle switches, as these are easier to use. Later more easily operated rocker switch came on. Modern switches with extensive rocker are called surface switch. The latest development, switches, switch the switch contacts when actuated and retain this shift position, while the rocker returns to its previous state after actuation.
During the development we came off the assembly earlier mainly applied onto the wall (surface) and now used largely sunk mounted switches (flush), since this type of termination reduces the risk of damage and thus possible exposure of live parts. On the other hand increase recessed electric wires, the risk of electric shock when wall work (eg nailing or drilling). To minimize this risk, installation zones have been established. Refer to installation .
A special version is the damp-proof switch Home Appliance , which is available also for surface or flush mounting.
Early light switches were made of porcelain made in the surface-mounted version and serves as a rotary switch with a rotating mechanism, then came those from Press Fiberboard (because of the impact sensitivity of chinaBakelite ) on. Today they are made of modern plastics . Chance are, especially in hospitals and other public facilities, even light switches from antimicrobially effective materials such as copper used to prevent infections
Electrical cables are for concealed installation in the so-called installation zones postponed. Since this installation zones are standardized, one can assume that outside this range no lines are laid. (Again, exceptions to the rule, so be careful!) Installation zones reduce the risk of accidents and damage during subsequent alterations, renovations, etc.
During installation, according to electrical codes (see also VDE ) of the outer conductor to switch the appliance so that after switching off no voltage is applied more.
Switches for lighting systems are usually designed for a current of 10 A. In practice, lighting and socket circuits to be backed up frequently combined with 16A. The fusing of the switch appliance with 16 A for fixed lighting is admissible because it can be assumed that the current conditional 10 A will not exceed the design of the luminaire. In the DIN VDE 0100-510: 2012-06 it says this in the section 512.1.2: “When choosing a piece of equipment of the intended operating current (at AC the rms value to be considered), the should lead it in undisturbed operation […]”
For switching the outlets there are two options: use of overcurrent protective devices with a rated current of I n ≤ 10 A or using installation switches with a rated current of I n ≥ 16 A (mostly multipolar switch).
Light switches used in the household home appliance installation is mostly in three parts: use , frame and rocker . The insert is of the non-visible part that contains the technical function. The rocker refers to the visible switch , the frame the border, so the transition to wall. Frames are one to five times and group switches, dimmers, sockets of all kinds, control and sensor into one unit.
This component has at least two end positions, in which the switch remains after pressing and so depending on the construction and position closes the circuit or interrupting. This type of control of the lighting is mainly used in homes.
The switch has an input and an output and two positions: “open” (open circuit) and “closed” (closed circuit).
Off switch can be found, for example, directly on the luminaire or in the connecting line, in the house installation in rooms with only a light switch. As component of the household wiring pure off are often not provided because can also be used as a switch for home appliances.
The changeover switch has one input and two outputs; but it can also be operated with two inputs and one output. He alternates between output A and output B. That is, when the circuit is closed over A, it is interrupted by B.
According to DIN VDE 0100-460: 2002-08 Section 465.1.2 single-pole switches may not be used in the neutral conductor. The misappropriation of change-over switches for the previously frequently used Hamburger circuit does not meet the current standards and is therefore prohibited.
Location: With two-way switches a lamp from two locations can be operated. Between the two switches at least two lines have to be drawn. In the cross-connect also two AC switches are used at the ends in home appliances.
A series switch denotes a double switch, so two independently operable switch to a common input and a respective output for each of the individual switch. Externally can this seen through a divided rocker. It can be replaced by two off switch.
The term series switches back to the time in which the switch in the form of rotary switches were made with four switching positions.
Location: serial connection , for example, lamps with two groups of lamps, 2 lighting groups
The intermediate switch has two inputs and two outputs, which are connected with two switch positions straight or crossed either, that is either input A with output A and B with B or A input with output B and B connected with A.Intermediate switch can also be used as a toggle switch or switch.
Location: In cross-connects as the third and further switch between two AC switches , for example, in rooms with light switches on the door and on each side of the bed. Cross circuits today often surge circuits with switches andpulse relay is replaced, because the wiring effort is lower here.
The button has only a basic position, in which he falls back by spring force as soon as you let go. So he sends only one signal (NO) or interrupts the current circuit (break) for a brief moment, he needs in the lighting control still is an additional control, a bistable relaywhich then the circuit keeps open or closed until the next control signal.
Location: switch circuits are used in the stairwell lighting and wherever more than two locations, the light is to be served.
Dimmers are light switches that allow addition to switching on and off the lighting and setting the brightness of the backlight by using a dial – or touch or dimmers by touching a sensor surface. They are also commonly used in table or floor lamps installed. They contain a phase control (for incandescent lamps and transformers) or phases from angle control (phase dimmer, z. B. for electronic transformers of low-voltage halogen systems)
Location: Wherever full or subdued lighting is needed. Off switch can be except for fluorescent lamps replaced by a suitable dimmer; in those with an electronic ballast dimming is required.
Twilight switch off automatically when an adjustable brightness value is exceeded or undershot. They are used as a light switch or roller shutter switch for shading. They have a hysteresis and usually delay circuits, not continuously switched on and off, if the ambient brightness varies little
Motion replace today increased external light switch. To turn the camera detects movement detection space, so for example when a person approaches the automatic outdoor lighting and after an adjustable time again.
Powered wireless light switches transmit the switching signal via radio to a receiver module that turns the lighting circuit on and off. The energy required for this is obtained from the switch operation: By pressing the switch, a piezoelectric element (is piezoelectricity ) actuated mechanically converted into electromagnetic energy. Energy-saving electronics makes it possible to produce from this energy coded radio signals having approximately 30 m range inside buildings (outdoor up to 300 m). Through the coding, a clear allocation between transmission and reception module is ensured.
Location: Without limitation. Particularly suitable for office buildings, in which the interior is often changed. Battery-less light switches can be mounted z. B. to glass walls or on wood, because no cable feed is needed. Also suitable for use in older buildings where no cable ducts must be created for this type of switch, or – for the same reason – in wooden houses.
They work similar to the battery-free devices, however, have as an energy source, usually a button cell . The battery life expectancy is up to about 10 years. Then a change of cell is needed. Opposite batteryless devices these often have the advantage of greater functionality. Furthermore, the sensed pressure point in battery-powered switches softer, since only one electrical contact must be closed here. For this reason, the installation height of battery-powered switches is now the same as ordinary switches during batteryless switches still have a significantly higher construction.