Dimmers, as the term suggests, changes the brightness or intensity of the light. With LED or light emitting diode dimmers, the intensity of the light may be varied through altering the RMS voltage passing through the lamp. LED dimmers manipulate the resistive incandescent and CFL or compact fluorescent light. They come in different sizes – from smaller dimmers for household use to larger and industrial or commercial use like theaters, halls, or architectural installations.
There are ways to manipulate the degree of brightness of light with the LED dimmer. It can either be controlled manually or through remote operation. Professional dimming needs employ digital control systems like DMX. Ethernet control systems may also be employed in connection with high-end systems. Modern dimmers use the technology of silicon controlled rectifiers (SCR) since they are highly efficient and have practically no limit as regards the speed variance like domestic dimmers which are controlled directly by the SCR. The main advantage of this type of dimmer is that it does not overheat and the brightness of the light is consistent and long lasting which adds up to the quality of it being cost effective. With a lot of dimmers in the market, it is greatly advised that the specifications be scrutinized first in order to achieve the maximum efficiency and provide for the lighting or dimming needs of a particular application.
In shopping for led dimmers, you have to look for the best in terms of quality and aesthetic or appeal that the dimmer would produce so that the entire room will achieve the best and desired lighting conditions. Several brand designs are available in the market, inter alia Cabana, Lenox, Kathy Ireland and Holkoetter provides better designs and variety as compared with other brands. With these designer shops, a wide range of selection of lighting styles are available, from traditional to contemporary to rustic to customized. LED lamps of various sizes fit into offices and household applications, both for indoor and outdoor use, as well as for security and high-end applications.
LED lamps are available for different parts of the room. There are lamps available for the kitchen, living room, bedroom, bathroom, and garage. The type of light used in a particular area of the house would transform your place into a look that describes elegance, luxury and sophistication. Custom made lamps further add up to the classic or personalized appearance of your place.
Triac LED Dimmers
TRIAC stands for Triode for Alternating Current. TRIAC dimmers are widely used to control the light conditions within households and offices for more than two decades. This device functions by changing between on state to off state of the light in a circuit in a fast manner by reducing the energy flow in the light switch.
The method used by TRIACs is likewise employed with incandescent lamps and fluorescent lights. However, the output is not as optimum as that with LEDs since the incandescent and fluorescent lamps use alternating current while the LEDs use direct current.
The major drawback in using LED lights with TRIAC dimmer is the flicker which is very noticeable. Findings in the medical field show that flickering lights may strain the eyes, cause fatigue, or in some cases induce epileptic seizures or attacks. Another drawback is that the LED may not respond well when the dimmer slide is adjusted or that the response is not that automatic, and sometimes, the light would turn off even though the dimmer slide is not completely off, say, just around 60 to 70 percent off. In cases where there are multiple LED lights controlled by one TRIAC dimmer, unexpected results may occur like some LEDs turning off while others are not dimmed. In other words, there may be inconsistencies in manner the LED are dimmed.
So how do we achieve the best result in terms of dimming lights with LED using TRIAC? Experts in this field recommend that specific dimmers be used with specific needs. Also, LED lamps with long life of 40,000 or more hours of operation and flicker free should be used to achieve the best result in terms of brightness. LED dimming drivers work by setting the LED lights to dimmed state. This is done by the reduction of the forward bias current employing the method of Pulse Width Modulation (PWM) through digital control. LED dimmers produced now are smaller in size and can be interfaced with any electrical switch circuit and may be installed or mounted even in minimal spaces.
LED Dimming
LEDs are in demand because the device is highly efficient, flexible, and requires minimal power. They are used as light indicators for activated controls, displays and lighting large areas. Dimming LEDs in terms of illuminated areas in order to achieve the desired lighting conditions and to conserve energy is the main consideration by using LEDs.
LED dimming is not that simple in operation. There are several issues that come along with the process of dimming. Among other things are the issue in power supply and dimming circuitry, shifting of LED color, flickering, thermal stress, mechanical stress, and EMI/RFI to name a few. With LED dimming, these issues will be addressed and resolved.
There must be a steady supply of current or voltage supplying the LED lights. What happens when the forward bias current is reduced in LED lights is that there will be a slight dimming and if reduction is sustained would drop to zero output light.
Pulse Width Modulation (PWM) is the process used in dimming LED. PWM is usually used by dimming drivers. This is a method of sending information via series of pulses. The intensity of the LED light varies as the PWM manipulates the width of the pulse and the duty cycle. This process is done by cutting the supply of current for short intervals thereby causing LED to turn off but before the light turns completely off, the current supply is restored, and the result is LED dimming. The frequency of this turn on-off state ranges from hundred to hundreds of thousands per second. With this, the LED will appear to just appear to produce a dimming light and not flicker. The issue of reducing the life span of the LED lamp is discarded as the dimming process would reduce the operating temperature of the lamp as the power is not constantly in the on state. In theory, the life span of the LED lamp is extended rather than reduced. The modulating cycle is done by an external controller or driver which is responsible in the dimming process and not the fitting itself.