Seen this in many houses, people upgrade their lighting setup and install a dimmer. Which works. But usually it also makes the lights flicker unintentionally, which is super annoying IMO.
Now, my understanding of electrical engineering is pretty rudimentary so I’d appreciate more something that explains the concept in a way that Cavewoman Mothra can understand rather than something technically accurate.
Thanks
Power coming into the house is AC which means 50-60 times a second the power goes from +110/240V to -110/240v.
LED lights run off DC power, so to change the power type a capacitor is somewhere that holds enough charge to keep the item working until the AC power is back to a usable positive value.
Dimmers limit the power going to the light, so the capacitor doesn’t charge enough to keep the light and circuitry on for the full negative swing of AC power.
This is ungodly rudimentary, and corrections are welcome. There is also many nuances I am missing.
Well written.
I think an important concept to introduce is Pulse Width Modulation, or PWM for short.
Normal AC Power coming out of wall looks like a sine wave, in that it smoothly cycles between +110/240V and -110/240V. This means that 50% of the time the voltage is positive and 50% of the time the voltage is negative.
PWM usually deals with signals which are either entirely on or off, with no transiton between them. This way, you can vary the amount of “power” delivered by varying how much of the time the signal is on and how much of the time it’s off.
Dimmers usually modify the sine way in a way that tries to accomplish the same thing, by chopping up the signal to make the effective “on” time be shorter than 50%.
With non-dimmable LEDs, this messes with the AC to DC circuitry in the lamp in the way slazer2au says, because the lamp doesn’t retain enough power between two on-cycles to stay on.
It should be noted that there are LED bulbs that will take a dimmed signal and convert it into a dimmer light. If you buy dimmer capable LEDs (though that still doesn’t work with all dimmers), you can get dimmed light without the flicker, and without having to resort to smart home crap.
