Sine Wave Dimmers

As flourescent lights need a minimum voltage and both compact flourescents and leds use electronics which rectifies the peak voltage provided a variable amplitude sine wave would fail to dim all of these types but in a slightly different way that the.

Sine wave dimmers.

It s called that because it alternates like a sine wave 60 times a second. This dimming technique is used for capacitive loads evsa. With phase control the voltage is cut off before the end of the sine wave so that only the first part is transmitted. Forward phase control forward phase control uses a dimmer that chops each half cycle of the power sine wave.

What does triac mean. This wave combines the aforementioned. Dimmers change the shape of the ac wave by chopping off part of it. Sometimes both leading and trailing edge phase control is possible.

This reduces the power available to the bulb which becomes less bright. Extending the period of time that the power is off during the half cycle results in a lower power output to the load. Sine wave dimmers are more efficient then comparable ssr and scr dimmers they are able to operate much faster be much quieter and still achieve the same efficiency. Power is off during the initial part of each half cycle and then turns on.

Sine wave and dc dimming. This is because line voltage dimming leds react to the hard phase angle that s present in both forward and reverse phase dimming which sinewave dimmers were designed to eliminate. Incandescent filament lamps would dim well on the waveform you propose but then they work well with conventional triac phase shift dimmers.