I have a buzzing sound coming from in ceiling light fixtures.
The fixtures are Liton LH1499IC (https://liton.com/ic-double-wall-housing-51083.html)
- These fixtures are connected to a dimmer switch
- Buzzing from the fixtures gets worse over time (as the light stays on)
- Buzzing gets worse with full brightness
- Buzzing gets worse if I completely remove the bulb but have the dimmer ON
- Buzzing 100% comes from the fixture itself and not the bulb, I can hear it from inside the fixture and as mentioned, if the bulb is completly removed the fixture buzzes worse
- Bulbs are 12V 50W which is what the fixture says to use. I tried changing to 12V 30W and 5W just to see what happens and the buzzing actually got much worse with the 5W as well
My first thought was to buy new fixtures and replace the old ones, but looking at the picture of that fixture it looks like its going to be alot of work (i've never replaced light fixtures before).
Next thought was could there be a relationship to the dimmer switch?
To be clear, the dimmer has no sound or buzzing whatsoever. But is it possible the wrong dimmer switch is connected and that is creating a buzz downstream at the fixture?
Dimmer is Lutron SLV-600P (https://www.lutron.com/en-US/Products/Pages/StandAloneControls/Dimmers-Switches/SkylarkDimmer/ModelNumbers.aspx)
- 120 V / 600 VA (450 W)
- I have 4 light fixtures connected to it, those are 12V, 50W each. MR-16
Bulbs are Osram 12V 50W MR-16 base bulbs
Is there any rule of thumb I can use in determining if the correct dimmer switch is paired to the correct fixture, or does it not matter? I'm essentially both hoping and wondering there is an easier solution to this problem then changing the fixtures
As you can tell, I'm a total noob.
Any help is much appreciated!
Best Answer
This is not a simple light fixture. It uses a TRANSFORMER.
Dimmers are tricky devices. While conceptually they adjust the incoming current with a variable resistance, in reality they are far more complex. The end result is that for direct use with incandescent & halogen bulbs, all dimmers work well. For use with dimmer-compatible (some are, some are not) LED or fluorescent bulbs, most modern dimmers (they will specify LED compatibility, as your Lutron does), they will work well.
However, your light fixtures include a transformer. That takes the 120V power and takes it down to 12V needed by the specified bulbs. That process is most definitely not compatible with a typical dimmer. The "right" way to dim such lights would be to dim them after the transformer. There are lights designed to work that way, but not your standard off-the-shelf residential stuff.
Update: Your dimmer (SLV-600P) is supposed to be compatible with Magnetic Low-Voltage fixtures. So it is basically "the right stuff". However, something is clearly going wrong, and my recommendations still stand, primarily because LED lighting has gotten cheaper and better (more reliable, better color) over the last several years and will save a lot in energy costs.
End result: Your dimmer is modern and fine. Your bulbs are "plain" and, in and of themselves, likely dimmer compatible. But your fixtures are not dimmer compatible.
Options:
1 - Replace the dimmer with an ordinary ($1 - $3) switch. No dimming. No buzzing.
2 - Replace the fixtures with your choice of: