When you dim a light or light source, you’re not lowering the voltage, you’re actually removing power from the circuit. If you’re going to do forward phase dimming, that means you’re chopping off the forward part of the sine-wave on the “positive current” end, and the back part on the “negative current” end. This kind of dimming is very hard on drivers of an electronic kind because there are surges of current through the circuit. However, if the voltage is ridden gently, and then just shut off, it ends up being much easier on the electronic circuitry. This is called reverse phase dimming. The difference is most dramatically seen in failure of equipment over time. Forward phase dimming was discovered first, and quickly became the status quo, the degradation of which being factored into engineering design. But savvy engineers realized there was another way to go about the same effect without damaging the equipment so much, and voila! Reverse phase dimming.



When a light is dimmed via forward phase dimming, it’s not that the power has been reduced such that the light is now half as bright, it’s that it’s blinking on and off in a way the human eye can’t really register. So the same voltage is coming through, but some of the power is being strangled off, as it were. Electronic Low Voltage (ELV), and other options to specify reverse phase. The voltage is ridden to a certain point and then cut off, producing the dimming effect while simultaneously conserving energy.



LED options usually use an ELV reverse-phase option because it prevents unnecessary power surges, conserves energy, and conserves lighting application ability. You’ll be able to apply the advantage of a light more cogently should its energy principles be engineered more cohesively.

LED power supplies and lights, as well as ELV options, are really the future of lighting. As better alternatives arise, naturally they get used more. If you can save money over time using options that require less power and render the same result, why wouldn’t you? It is possible that in the near future, LEDs will completely replace most incandescent options. As it stands, the additional expense of LEDs often discourages buyers; but this shouldn’t be the case. Initial expense is greater with LEDs, but the savings and dependability they offer saves users hundreds of dollars in the long run.