Search results
Results from the WOW.Com Content Network
In visual perception, flicker is a human-visible change in luminance of an illuminated surface or light source which can be due to fluctuations of the light source itself, or due to external causes such as due to rapid fluctuations in the voltage of the power supply (power-line flicker) or incompatibility with an external dimmer.
When the dimmer is at 50% power, the switches are switching their highest voltage (>325 V in Europe) and the sudden surge of power causes the coils on the inductor to move, creating a buzzing sound associated with some types of dimmer; this same effect can be heard in the filaments of the incandescent lamps as "singing". The suppression ...
Most ceiling fans typically feature a small slide switch on the motor body of the fan itself, which controls the direction in which the fan rotates. In one position, the fan is caused to rotate clockwise, in the other position the fan is caused to rotate counter-clockwise.
Manually operated on/off switches may be substituted by dimmer switches that allow controlling the brightness of lamps as well as turning them on or off, time-controlled switches, occupancy-sensing switches, and remotely controlled switches and dimmers. Light switches are also found in flashlights, vehicles, and other devices.
The dimmer switch used in conjunction with a dimmable CFL must be matched to its power consumption range; [58] many dimmers installed for use with incandescent bulbs do not function acceptably below 40 W, whereas CFL applications commonly draw power in the range 7–20 W. Dimmable CFLs have been marketed before suitable dimmers are available.
The requirements of a flicker measurement equipment are defined in the international electro-technical standard IEC 61000-4-15. [2]A flickermeter is composed of several function blocks which simulate a 230 V/60 W or a 120 V/60 W incandescent lamp (reference lamp) and the human perception system (eye-brain model).
Compared to a rheostat-based circuit, the use of a thyristor greatly increases efficiency, as far less waste heat is generated. Dimming lights with a solid state dimmer also reduces total power draw, unlike rheostat dimmers. Spira's design (and most modern dimmers) rely on the use of AC power, and on the characteristics of incandescent lights.
Flicker noise is a type of electronic noise with a 1/f power spectral density. It is therefore often referred to as 1/ f noise or pink noise , though these terms have wider definitions. It occurs in almost all electronic devices and can show up with a variety of other effects, such as impurities in a conductive channel, generation and ...