Non-dimmable LED bulbs are dimmable

markr6

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What's going on when you put a "non-dimmable" bulb in a socket with an incandescent in another socket (same lamp/chanderlier)? I noticed this works. Not only does it work, it works BETTER than bulbs specifically labeled "dimmable". Talk about irony!

Usually all the LEDs I've tried on my dimmers go down about 40% then up to 100%, and the transition is rough. With the non-dimmable + incandescent combo, it's pretty much 0-100% and a smooth transition.

Very strange! Too bad all LEDs can't do this by themselves. I really like the dimmer switches I have but they're not the fancy ones designed for LEDs.
 

FRITZHID

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The incan bulbs act as a "ballast" of sorts, allowing the triac to fully fire and cut off properly whilst smoothing the power allowing the LED bulbs to activate full time although at a lower power rating.
 

markr6

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The incan bulbs act as a "ballast" of sorts, allowing the triac to fully fire and cut off properly whilst smoothing the power allowing the LED bulbs to activate full time although at a lower power rating.

Thanks! If these didn't look so ridiculous in a chandelier to being with, I'd try to wire up a single incan and hide it somewhere in the junction box for this full range of dimming.
 

FRITZHID

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Pull the ceramic resistor out of an electric "wax scent burner" and wire it in somewhere it can't cook anything and it should provide enough "ballast" for the dimmer and LED bulb combo.
 

JoakimFlorence

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It's basically like wiring a resistor in parallel with the LED bulb. There's more resistance through the incandescent than there is through the LED section. Even if the supply of power is turned down, the LED is still going to be able to draw enough power to stay lit.

A second possibility: At lower power supply levels the current flowing through the LED circuitry isn't a smooth flow. This could cause an interaction with the smooth flow of current through the triac in the dimmer circuitry. Having an alternate path of continuous current flow through the incandescent would help avoid this issue.


On a completely separate but related off-topic, if they were to combine an LED lamp wired in series with an incandescent bulb, they could potentially dispose of the requirement for the power supply circuitry normally contained in an LED bulb, increasing the efficiency of the LED. Combining LED with incandescent light carries some additional benefit as well in the realm of color rendering. Of course they'd probably want to specially design an incandescent bulb for this application to optimally function at a lower voltage. (I realize this is a kind of whacky idea, off-topic, but it's sort of interesting to think about)
 
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markr6

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I just have a hard time upgrading to "proper" dimmer switches. Not only for the higher cost, but the functionally. They all seem to have an on-off plus the slider. What a PITA! Right now I have the basic $6 toggle switch dimmer; it looks like any standard switch but it's a dimmer. So you can go into a room and not have to mess with "selecting" the brightness before (or after) turning on. A quick flick and it's at 100%. A small nudge and it's at the lowest level (filament barely glowing, great for waking up in the middle of the night).
 

mcnels1

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The Leviton 6672-1LW dimmer just slides from off to low through high.
 

markr6

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The Leviton 6672-1LW dimmer just slides from off to low through high.

I could probably settle for that. I really like the toggles since they're easier to flick, and fit the standard switch plates. But I assume they make a plate with one big cutout and 1 or 2 standard as well (fan, other light, etc)
 
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Speaking of it's a PITA. LED dimmers need to be matched with the LED they'll be controlling. They don't all play nice with each other. I was at Home Depot about a year ago and called the Cree 1 800 number. I told the service tech all the different makes of dimmers that were in stock. He check them all, but couldn't assure me any would function properly with their LED's.

http://luxreview.com/article/2015/07/dos-and-dont-s-for-led-dimming

~ Chance
 
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My reason for posting was to help members from going through the time and trouble of purchasing a newer dimmer, installing it with a new, dimmable LED, only to discover the results were totally subpar. The fixtures were in bedrooms and they only housed two bulbs. Big PITA to go through for flickering light accompanied by a totally unacceptable BZZZZZZing sound.

~ Chance
 

N8N

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I just posted, amazingly I'm super impressed with the dimming performance of some Feit Electric "60W" bulbs that I picked up at Costco today. If they last, they're shockingly good.

Adding a ballast resistor will negate the energy savings of using LEDs. At that point you might as well run incans.
 
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