Can someone ELI5 why often lights set up with a dimmer also flicker? (mander.xyz)

submitted 2 months ago by Mothra@mander.xyz to c/asklemmy@lemmy.ml

31 comments fedilink hide all child comments

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

you are viewing a single comment's thread
view the rest of the comments

[-] jjagaimo@lemmy.ca 19 points 2 months ago* (last edited 2 months ago)

Dimmers will typically use a triac which cuts up the sinusoidal waveform. It doesnt actually lower the amplitude per se, but it limits the fraction of the time the waveform is on. Kinda like this. This means that a lot of the time the led isnt gettingas much or any power. The average power will be lower, and if the LED driving circuitry isnt designed to compensate for this, the LED will flicker.

Clarification on triacs: they get turned on a certain fraction of the way into the cycle. Triacs will stay on until the voltage across them is 0. Conveniently the zero-crossing of the AC wave (when the wall voltage crosses zero to start foing negative or from negative to positive) does just that.

this post was submitted on 17 Aug 2024

79 points (98.8% liked)

Asklemmy

43822 readers

876 users here now

A loosely moderated place to ask open-ended questions

Search asklemmy 🔍

If your post meets the following criteria, it's welcome here!

Open-ended question
Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
Not ad nauseam inducing: please make sure it is a question that would be new to most members
An actual topic of discussion

Looking for support?

Looking for a community?

Lemmyverse: community search
sub.rehab: maps old subreddits to fediverse options, marks official as such
!lemmy411@lemmy.ca: a community for finding communities

~Icon~ ~by~ ~@Double_A@discuss.tchncs.de~

founded 5 years ago

MODERATORS