Flickering LEDs?

Homerboy

Lifer
Mar 1, 2000
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I just installed a new light fixture with LED bulbs and it's on a dimmer.
Turned all the way up, the lights are quite dim and flickering:


I'm pretty sure this is due to the fact the dimmer switch is older (like 20 years) and not LED "ready", right? So I'd need to get a new dimmer switch as well?
 

Homerboy

Lifer
Mar 1, 2000
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Actually, I think I figured this out.

I was using the bulbs that came with the fixture. I had already purchased bulbs as I didn't know they were included. I made sure to get dimmable LEDs, but when I saw bulbs were included in the box I set the ones I bought aside and used the included ones.

After posting I looked at the box and it did not mention if those bulbs were dimmable or not. So I opened the ones I bought, put ONE in and all 4 dimmed just fine (which is odd). I replaced all 4 that were included with the ones I bought and it's dimming away.

Side note; the damned fixture hangs about 2" too low, but the way my shoulders are burning right now, ta hell if I'm fixing that.
 

Steltek

Diamond Member
Mar 29, 2001
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Sometimes, better quality bulbs will help; others, you may also have to swap the switch. There are also situations were nothing short of entirely replacing an older fixture and switch will resolve LED flickering.

I've got a 10 year old ceiling fan in my dining room that has an oddball light fixture that holds five standard 40 watt incandescent bulbs. Replacing them with LED bulbs results in the flicker show from hell after about 10 minutes. The light fixture on the fan isn't replaceable, but the fan runs great so I really don't want to replace it. I've previously pulled the fan down and checked the wiring for safety (traced it from the light fixture through the fan all the way back to the breaker box), but there is no apparent problem with it. Swapping the wall switch for a new one rated specifically for LEDs didn't do anything to resolve the problem either.

As a stopgap, I discovered accidentally that so long as I have at least one incandescent bulb installed in the fixture, the LEDs won't flicker at all when the fixture is dimmed. Go figure.
 
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mindless1

Diamond Member
Aug 11, 2001
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Yes if you want to use an old triac type dimmer, the bulbs must be designed for this, otherwise the outcome is unpredictable but often what happens is the bulb has a very small, non-linear range of dimming (quickly) from the dimmer control and is difficult to set much below ~50% brightness.
 

BoomerD

No Lifer
Feb 26, 2006
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I have a hanging light in my dining room on a dimmer...the LED's flicker, I have 3 "can" lights in the kitchen on a dimmer...those LED's flicker. I switched both dimmers over to quality dimmers for LED's, hoping that would fix the problem...nope.
 

Homerboy

Lifer
Mar 1, 2000
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The flickering did stop once I put the dimmable bulbs in. I will say though that there are four, 4.5W LEDs that are supposed to be equivalent of 60W incandescent. There's no way those that fixture is producing a perceived 240W of light.
 

Steltek

Diamond Member
Mar 29, 2001
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I have a hanging light in my dining room on a dimmer...the LED's flicker, I have 3 "can" lights in the kitchen on a dimmer...those LED's flicker. I switched both dimmers over to quality dimmers for LED's, hoping that would fix the problem...nope.

If you are using cheapo LEDs, try a different brand of higher quality LED bulbs in each.

If this doesn't work, as a last resort find an incandescent bulb that closely matches the LED bulbs in color (so that it doesn't stand out) and swap a single LED bulb in each circuit for the incandescent. There is a very good chance this might eliminate most of the flicker as the incandescent bulb will even out the voltage spikes from the LEDs.

The hard part is finding an incandescent that closely matches the LEDs - it usually isn't easy as many LED manufacturers (even name brands) outright lie about the lumen output and color of their bulbs (lots of them sell 50-watt equivalent LEDs labeled as 60 watt equivalent, and it gets way worse at 75/100 watt equivalencies. The less said about the advertised colors the better).
 

Homerboy

Lifer
Mar 1, 2000
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If you are using cheapo LEDs, try a different brand of higher quality LED bulbs in each.

If this doesn't work, as a last resort find an incandescent bulb that closely matches the LED bulbs in color (so that it doesn't stand out) and swap a single LED bulb in each circuit for the incandescent. There is a very good chance this might eliminate most of the flicker as the incandescent bulb will even out the voltage spikes from the LEDs.

The hard part is finding an incandescent that closely matches the LEDs - it usually isn't easy as many LED manufacturers (even name brands) outright lie about the lumen output and color of their bulbs (lots of them sell 50-watt equivalent LEDs labeled as 60 watt equivalent, and it gets way worse at 75/100 watt equivalencies. The less said about the advertised colors the better).

ha! See my previous post. Those 4x4.5W LEDs I got are NOT putting out 240W of light.
 

mindless1

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Aug 11, 2001
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^ Typical budget bulbs are still around 100lm/W so 8W LED bulb ~ 800lm ~ 60W incandescent.

However, there is another potential factor. The bulbs with only a dozen or so (or less) chip LEDs on an mPCB operate from a driver circuit in the base of the bulb (except the cheapest of junk using only a series resistor) but the candelabra style with a floating high-series-count of dies like the following, may just be flickering because there's a partial break in the series, aka defective. That type usually does not have a current regulating driver in the base.

 

Homerboy

Lifer
Mar 1, 2000
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^ Typical budget bulbs are still around 100lm/W so 8W LED bulb ~ 800lm ~ 60W incandescent.

However, there is another potential factor. The bulbs with only a dozen or so (or less) chip LEDs on an mPCB operate from a driver circuit in the base of the bulb (except the cheapest of junk using only a series resistor) but the candelabra style with a floating high-series-count of dies like the following, may just be flickering because there's a partial break in the series, aka defective. That type usually does not have a current regulating driver in the base.


Interesting.

So, the fixture I have says it requires the following:
Takes four bulbs and compatible with any 9W LED or 40W Type "B" or 13W CFL

I bought these:
(so I do take the "240W equivalent" statements back)

Do you have any bulbs you might specifically recommend?
 

mindless1

Diamond Member
Aug 11, 2001
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I don't have any that I'd recommend. My candelabras are so seldom used that the power savings isn't a factor and same incan bulbs have been in them for many years, may never burn out.
 

BoomerD

No Lifer
Feb 26, 2006
65,650
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If you are using cheapo LEDs, try a different brand of higher quality LED bulbs in each.

If this doesn't work, as a last resort find an incandescent bulb that closely matches the LED bulbs in color (so that it doesn't stand out) and swap a single LED bulb in each circuit for the incandescent. There is a very good chance this might eliminate most of the flicker as the incandescent bulb will even out the voltage spikes from the LEDs.

The hard part is finding an incandescent that closely matches the LEDs - it usually isn't easy as many LED manufacturers (even name brands) outright lie about the lumen output and color of their bulbs (lots of them sell 50-watt equivalent LEDs labeled as 60 watt equivalent, and it gets way worse at 75/100 watt equivalencies. The less said about the advertised colors the better).

I don't know about "cheapo," they're from Costco. With the brands sold there, you USUALLY get better quality...but never know for sure.
 

purbeast0

No Lifer
Sep 13, 2001
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I had this issue with LED lights I put in my cones in my main living room. Once I installed a new switch the flickering went away.