Dimmable LED incandescent replacements

[Curious.George]

Has anyone had success using dimmable LED replacement bulbs? Which brand(s) and which dimmer(s)?

Despite using "recommended" (by lamp manufacturer) dimmers, we seem to end up with low frequency (~2-3Hz) flicker at certain intensity levels.

We're using 2 x 75W BR20's for the "problem" currently -- wanting to increase to 10 on that branch circuit (dimmer rated at 600W so it is currently only operating at ~5% load capacity)

[sam_sam_sam]

Re: Dimmable LED incandescent replacements

This is very hard to find a good quality LED bulbs that are dimmable
The dimmer are pretty much the same story

With out building one your self this about only thing that I can tell you at this point

I have wanted to this myself but I have not figured out or found a ready made solution

Now you can find ready made LED switching power supply but I have so far not found one that has the dimmer build into it

Now you can find the dimmers and I have not tried them yet either because I do not know how many LED I want to run and what wattage and so on

Now if this is a project that you would like to work on I might be able to put some input into and do some testing as well

I have use some PWM power supply on LED before and the results were not bad but you could not dim all the down maybe down to 10 to 15 percent and this just a guess

What I might try use is some capacitors on the output to smooth out the pluses which might work I did this on a PWM Servo value ( because it was hunting ) ( still in use today) and the results were pretty good for this application approach but weather this would work on some LEDs lights this is a hole another story

I will have give this a try and see if this approach will work on LEDs lights or not

*** How easy it to find the PWM signal in this dimmer device ***
*** Is the PWM signal being done with a micro controller ***
***Or is it being done with a PWM ic chip and if so which one ***
*** Or is this being done in the switching power supply to adjust the voltage output or current output ***

[Curious.George]

Re: Dimmable LED incandescent replacements

This is very hard to find a good quality LED bulbs that are dimmable. The dimmer are pretty much the same story

I think the bulbs are the bigger part of the problem. They've already got "smarts" to figure out how to drive the LEDs off of the AC signal so need a way to sort out when that "AC" has been modulated (by the dimmer) and make sense of it.

We've some bulbs that dim rather nicely -- but, at certain points, flicker at several Hz. This is just outright annoying.

And, the RFI of others have made OTA radio reception impractical.

Now you can find ready made LED switching power supply but I have so far not found one that has the dimmer build into it

That wouldn't work for "bulbs" that are intended to be powered off the (dimmed) AC mains.

I have "bare diodes" that I can dim nicely with an adjustable powersupply. But, those have dedicated wiring; the bulbs that I'm interested in dimming are "general area lighting" and I've no desire to rewire the house just to support a bastardized scheme to drive them.

Now you can find the dimmers and I have not tried them yet either because I do not know how many LED I want to run and what wattage and so on

We'd replaced branch circuits driving hundreds of watts of incandescents with LED "bulbs" (A19's). If you can drive an incandescent lamp, you can typically drive 5 or 6 times as many "equivalent watts" of LED lamps with the same dimmer.

I have use some PWM power supply on LED before and the results were not bad but you could not dim all the down maybe down to 10 to 15 percent and this just a guess

CFLs are even worse -- more like 50%. We have LOTS of incandescents that we regularly dim to "minimum" which gives just enough light for "sleepytime eyes" to see what's in the room (when overnight visitors wake, they can find their way around without having to turn the lights "on"). But, they are dim enough that eyes that haven't yet adjusted to the darkness can't see...

For CFLs, this is laughable.

*** How easy it to find the PWM signal in this dimmer device ***
*** Is the PWM signal being done with a micro controller ***
***Or is it being done with a PWM ic chip and if so which one ***
*** Or is this being done in the switching power supply to adjust the voltage output or current output ***

The dimmer is just mangling the AC mains as it would for an incandescent bulb. The LED driver is encased within the COTS LED (incandescent replacement) "bulbs"

[diif]

Re: Dimmable LED incandescent replacements

I'm dimming cheap no name GU10 3x1W bulbs here. I had to buy a special type of dimmer for them so there was no buzzing.

[RJARRRPCGP]

Re: Dimmable LED incandescent replacements

That's probably because most AC dimmers, act like a run-of-the-mill UPS inverter. You will hear buzzing much like CRTs on a cheap UPS inverter.

[stj]

Re: Dimmable LED incandescent replacements

no, it's because regular dimmers have a big choke in them and mains is in the audio-spectrum

[delaware74b]

Re: Dimmable LED incandescent replacements

Dimmable LED lamps are an ever-changing technology. Few lamps are the same in 2 years from today.

I have found a series of dimmers that have reliably worked with these lamps. The Lutron CL-series dimmers appear to work with 90% of the line-voltage dimmable LED lamps. These dimmers are a hybrid which handle 600 watts incandescent/halogen and 150 watts LED or compact fluorescent (remember those things). There are also higher wattage units available but you won't find them at big blue or big orange - special order at an electrical supply house and $$$$$

[Curious.George]

Re: Dimmable LED incandescent replacements

I have found a series of dimmers that have reliably worked with these lamps. The Lutron CL-series dimmers appear to work with 90% of the line-voltage dimmable LED lamps. These dimmers are a hybrid which handle 600 watts incandescent/halogen and 150 watts LED or compact fluorescent (remember those things). There are also higher wattage units available but you won't find them at big blue or big orange - special order at an electrical supply house and $$$$$

That's what we have. The problem doesn't appear to be IN the dimmer but, rather, in how the lamp handles a certain "operating point" -- they dim linearly to a very low level. But, just before reaching 100% ON, enter a narrow region where they flicker very visibly.

Note that none of our applications would ever see 150W of LED load (most lamps on a circuit is 8 and figure ~12W each, max)

I may try swapping out the dimmer (we have lots of them, here) to see if that changes anything. It's obvious that the lamps behave identically so changing them would likely be ineffective.

[sam_sam_sam]

Re: Dimmable LED incandescent replacements

If they are incandescent lamp dimmers then that might be the problem because of the way they are made for incandescent lamps unless dimmer made really bad you would not notice it but with LED lamps you would notice it

One other note I have taken apart LED lamps before and a lot of ones I have taken apart the switching power supply are crap

I have also seen that a lot of LED modules are also crappy made as well if you try slowly bring the voltage ( powering from a bench power supply) they will flicker until you bring up the minimum voltage up for all the LEDs to light then everything good after that

The LED modules run on a voltage from 24 volt to sometimes over 60 volts if you happen to find some 48 volt LED modules the switching power supply are easily found on EBAY

The biggest problem is finding good quality LED modules and I have been having a lot of trouble finding good quality LED modules with out paying an arm and a leg for them

[tester272001]

Re: Dimmable LED incandescent replacements

I have had allot of success with Feit brand dimmable LED retrofits. The color temperature is always less yellow than incandescent but acceptable.