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Silencing light dimmers

Posted: Tue Apr 04, 2017 1:08 am
by lm
Hi

After a major remodeling, I have now several light dimmers instead of plain on/off switches in my apartment. They all buzz more or less when the lights are on, audible when it is otherwise quiet.

I would love to hear any experiences in silencing these things?

EDIT: Answered to questions below:

I have 3 different brands of led panels, which all claim to be dimmable by triac dimmers and all have a power supply unit which is separate from the panel. Then I have one 12V halogen with an iron core transformer and that has a thyristor dimmer.

All of these dimmers buzz, especially the one for the halogen. Buzzing happens on all dimming levels but the noise changes depending on the setting.

I used to have CFLs but I got rid of all of them during remodeling due to slow startup, taking a long time to achieve full brightness and still needing to be replaced every now and then. Incandescent lamps I haven't had in a long time.

Re: Silencing light dimmers

Posted: Tue Apr 04, 2017 1:55 am
by edh
I personally don't like dimmer switches as they don't work with many energy saving bulbs, thus limiting bulb choices. What bulbs are you using?

Do they buzz when at full brightness or part brightness?

Re: Silencing light dimmers

Posted: Tue Apr 04, 2017 4:54 am
by NeilBlanchard
This is usually an interaction between the dimmer and the bulb(s) you are using. To see if it is the dimmer all on it's own, try using an incandescent bulb. If it still buzzes, then you need new dimmers. LED and CFL bulbs have driver circuits, and even if they are rated as dimmable, they vary in how they work; or at least what frequency they work at.

Dimmers are often PWM, as well, so the two PWM circuits - one in the dimmer and the one in the bulb - interact and resonate.

Re: Silencing light dimmers

Posted: Tue Apr 04, 2017 7:32 am
by CA_Steve
I ran into this when replacing older CFLs in some of the rooms with LEDs and the resultant increase in lumens made me add some dimmers :)

See if your brand of dimmer has a website with bulb compatability list for your dimmer model...conversely, see if your bulb has a website with compatible dimmers. I know Lutron and Leviton dimmers do..as well as GE LEDs.

Re: Silencing light dimmers

Posted: Tue Apr 04, 2017 9:13 am
by lm
Hi

Thx for comments. I edited the original post to answer them.

I was considering to put some bitumen dampening mat inside the rotary dial, as the noise increases if I pull the rotary dial off and by doing that expose the metal parts of the actual dimmer. Does that sound completely stupid?

Being located in Finland my brands are probably a bit different than in USA but the concept of compatibility lists is valid in general. It's just that I got these dimmers already, they were installed by the electrician based on what bulbs I explained to him I would be using.

Re: Silencing light dimmers

Posted: Wed Apr 05, 2017 5:52 am
by lm
Do you guys in general get completely inaudible dimmers? As in silent in an otherwise quiet room? As in not able to hear that you are using dimmers?

Given that I have problems with ALL of my dimmers with all different lights I have from two different renovations and two different electricians, it seems to me like silent dimmers do not even exist. Do they?

Re: Silencing light dimmers

Posted: Wed Apr 05, 2017 6:40 am
by CA_Steve
I have no noise from the three dimmers I use to control LEDs. However, I do get the occasional buzzy LED.

Re: Silencing light dimmers

Posted: Wed Apr 05, 2017 12:13 pm
by NeilBlanchard
The dimmers in my house are silent, and I have only had a noisy CFL bulb; which seemed to be just that unit.