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I just switched from incandescent to LED in my kitchen fixture. This thing is 16 60 watt bulbs. The switch is rated for 1000 watts. The bulbs are Phillips.

The light flicker at certain spots. Even on the highest setting I get some strobing.

So I'm going to upgrade to a better switch. Is there anything I should look for? Is brand name the best guide?

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    What make and model is the existing dimmer? – ThreePhaseEel Sep 24 '17 at 2:54
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    You mean a long time ago you used 60 watt incandescents, and now you have LEDs of about the same brightness (500-800 lumens depending on how well they're aimed). So probably 10-12W actual, or 160-200W total. Are these LEDs rated for dimming? Do the LED instructions have any advice as to which units they are most compatible with? – Harper - Reinstate Monica Sep 24 '17 at 2:55
  • @ThreePhaseEel I'm not sure. I'd have to pull it. Knowing myself, I picked the cheapest option. – jqning Sep 24 '17 at 3:02
  • @Harper I don't know about the long time part, it's been about five years. The LEDs are 8.5watt (I should have checked that) Aaaaaand I double checked the dimmable rating. It looks like I picked the dimmable version for my order, but when I changed the quantity I also changed the bulb type, which ordered nondimmable. So this question is answered! Dang it. – jqning Sep 24 '17 at 3:10
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    Nah, give it to ThreePhaseEel, he covered it impeccably. – Harper - Reinstate Monica Sep 24 '17 at 3:40
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Cheap dimmers are cheap for a reason

Cheap dimmers often omit the extra parts needed to generate clean output, without EMI, asymmetric waveforms, or other things that can confuse the fiddly business involved in getting a LED to dim solely off a phase-controlled 120VAC power input.

Get a decent spec-grade dimmer intended for LED/CFL use (Lutron makes good stuff, and their support is solid too, if you want a brand name to go by) instead of the builder-grade cheapie you threw in there if the problem persists with dimmable bulbs. An air-gap shutoff is a good idea as well (all the Lutron dimmers have it, and any spec-grade dimmer should have it).

And make sure your bulbs are dimmable, too

LED drivers, whether integral or external, have to explicitly support phase-control dimming in order for it to work -- it will not work properly "by accident" as you found out the hard way. So, lesson learned: make sure your bulbs are dimmable when you're using them on an LED compatible dimmer.

  • I would also recommend you get a dimmer with some sort of a mechanical shut off. If you get an electronic shut off it might leak a small amount of current causing your LED lights to flicker or glow at a low level. – Retired Master Electrician Sep 24 '17 at 14:06

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