TRIAC Dimming: This is the most commonly recognized dimming type, with TRIAC Dimmers found in most Home Centers and hardware stores. TRIAC (TRIode for Alternating Current) dimmers operate by modifying the voltage waveform, reducing the amount of power input to the device being controlled. Reducing the input power will result in a corresponding reduction in a power supply's output voltage/current or a decrease in the lumen output of a light fixture. TRIAC dimmers come in two variations: Forward Phase and Reverse Phase
MLV (Magnetic Low Voltage): Also known as Leading Edge or Forward Phase Dimming, this type of dimming controls the amount of power delivered to the load by chopping off the leading edge of the AC waveform, reducing the power supplied and thus dimming the output.
ELV (Electronic Low Voltage): Also known as Trailing Edge or Reverse Phase Dimming, this type of dimming controls the amount of power delivered to the load by chopping off the trailing edge of the AC waveform. These dimmers can result in smoother dimming performance, reduced flicker, and reduced hum, especially with electronic low voltage (ELV) lighting.
0-10V Dimming: This type of dimming control is most commonly found in commercial applications. It works by varying a voltage from 0 to 10 VDC on dedicated dimming wires. The output of a power supply or light fixture is proportional to the voltage applied.
Pulse-Width Modulation (PWM) Dimming: This dimming control adjusts output by rapidly turning the output on and off at a fixed frequency. The proportion of on-time to total time sets the dimming percentage.
Potentiometer Dimming: Potentiometer dimming varies the output using a variable resistor, or potentiometer, to set the dimming level.