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A dimmer is an electronic brightness control for lamps and for power control of appliances. Dimmers reduce the effective voltage at the lamps by cutting off part of the phase and thus supplying only a partial phase of the mains voltage to the consumer. Voltage regulation is accomplished with thyristors or triacs using pulse width modulation and phase on or phase off control, depending on the load characteristics of the load.

Dimmers can control the brightness ofincandescent and halogen lamps. Gas discharge lamps cannot be dimmed via these dimmers because ionization requires a certain voltage level and gas discharge lamps cannot be re-ignited. The same applies to LED lights, which require a special dimmer.

Depending on the load characteristics, one uses phase-angle or phase-angle control. For inductive and resistive loads, such as incandescent lamps and high-voltage halogen lamps, phase angle control is used; for capacitive loads, such as low-voltage halogen lamps, phase angle control is used. In terms of principle, a distinction is made between analog and digital dimmers. Analog dimmers are controlled with analog control signals via a rotary knob, pushbutton or slider. The control voltages are between 1 V and 10 V, which is why the interfaces are also referred to as 1 to 10 V interfaces. Digital dimmers, on the other hand, work with a processor that digitally determines the switching time and usually regulates this between light and dark with 12-bitresolution, i.e. 4,096 steps. Corresponding dimmers can be controlled via the European Installation Bus( EIB), via Ethernet or the Digital Addressable Lighting Interface( DALI).

In terms of design, the dimmer function can be controlled via a slide or rotary control, or also via a touch-sensitive touch surface.

Englisch: dimmer
Updated at: 02.02.2016
#Words: 277
Links: brightness, power (P), voltage, phase, pulse width modulation (PWM)
Translations: DE

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