I have a light fixture in my bedroom with three 60 watt LEDs in it. I can hear a loud hissing noise coming from each light. I'm almost positive it's because there is just too much power flowing into the lights. How do I reduce the power running into the light bulbs?

A few side notes:

  • The switch its connected to is a brand new Lutron dimmer, specifically made for leds.
  • There use to be a ceiling fan where the light ballast is, which is possibly why there's way to much power running to it for just three 60 watt bulbs.

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  • Check for cockroaches. – Samuel May 7 '15 at 19:02
  • 3
    @Samuel STM has a SMPS chip called the VIPer. – Spehro Pefhany May 7 '15 at 19:06
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    It's saying "Help me, I'm way too bright for a bedroom!" in parseltounge. – Olin Lathrop May 7 '15 at 21:00

This noise is not from the bulb, it is from the LED driver. Each LED driver (it is a small circuit board usually inside the bulb, sometimes also called LED ballast) has an inductor inside (bunch of wire wound on a ferrite core). During operation, the current via this inductor rapidly appears and disappears. If the circuit is using cheap parts or is improperly designed, this may cause noise (see http://en.wikipedia.org/wiki/Coil_noise for more details).

The core problem is that your driver is not good enough -- maybe engineer made a mistake, maybe the factory did not put enough epoxy on the coils. The only easy way to fix it to to replace the driver.

There is a small chance that your problem is incompatibility between the dimmer and the driver, but in this case noise should disappear as you turn the brightness to maximum.

  • Thank you very much, detailed answer. Appreciate the time you took to explain this. The led's i have now where about 4$ each and are made by philips i will do a little digging and see who makes the best led builds and see if it fixes the problem. Thanks again man. – After_Sunset May 7 '15 at 22:13

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