Dimming LED Lamps

[SceneryDriver]

All,
Let me preface this by stating that while I do LOTS of LED lighting, and my main day-to-day is industrial controls, I do next to nothing with LED A19-style lamps that are line-voltage dimmed. Like... zilch.

With that said, what can people recommend for a single-way dimmer to control (3) 60W-equivalant LED lamps in a ceiling fixture? Kicker is, it's an existing installation and of course the original installer didn't include a neutral at the switch box (wired in 14-2 AC as a switch loop). Adding the noodle isn't a possibility (AC was run through brick before stucco was applied).

I tried a Lutron TGCL-153-PH-WH dimmer the client supplied, and got nowhere. It's supposed to be a 1-way / 3-way dimmer depending on how it's hooked up, but all I ever got it to do was toggle on and off - no dimming. It may have been a dodgy dimmer however, as I'm pretty sure the package was open, and I'm pretty sure that there were instructions missing. Is Lutron so low-rent these days as to make you look up the hookup instructions using Google?

I remember the good ol' days of incandescent dimming and two-wire dimmers. I realize that dimming (dimmable) LEDs is more complicated, but what are folks using these days? I'd love to pick whatever it is up at Home Depot this afternoon, so I can swing by the client on the way home and make them happy.


Thanks,

SceneryDriver

 

[SceneryDriver]

All,
Let me preface this by stating that while I do LOTS of LED lighting, and my main day-to-day is industrial controls, I do next to nothing with LED A19-style lamps that are line-voltage dimmed. Like... zilch.

With that said, what can people recommend for a single-way dimmer to control (3) 60W-equivalant LED lamps in a ceiling fixture? Kicker is, it's an existing installation and of course the original installer didn't include a neutral at the switch box (wired in 14-2 AC as a switch loop). Adding the noodle isn't a possibility (AC was run through brick before stucco was applied).

I tried a Lutron TGCL-153-PH-WH dimmer the client supplied, and got nowhere. It's supposed to be a 1-way / 3-way dimmer depending on how it's hooked up, but all I ever got it to do was toggle on and off - no dimming. It may have been a dodgy dimmer however, as I'm pretty sure the package was open, and I'm pretty sure that there were instructions missing. Is Lutron so low-rent these days as to make you look up the hookup instructions using Google?

I remember the good ol' days of incandescent dimming and two-wire dimmers. I realize that dimming (dimmable) LEDs is more complicated, but what are folks using these days? I'd love to pick whatever it is up at Home Depot this afternoon, so I can swing by the client on the way home and make them happy.


Thanks,

SceneryDriver

This somehow ended up in Calcs/Engineering. Mods, please move as appropriate. Apologies.

 

[LarryFine]

Due to so much LED/dimmer incompatibility, most LED manufacturers have a list of compatible dimmer models. That's where I'd start.

 

[gar]

190121-1420 EST

SceneryDriver:

My opinion from very limited experiments.

CREE 60 W equivalent, meaning actual 9.5 W, that I have played with dim very well over a wide range with either a Variac dimmer, variable sine wave voltage, and with appropriate phase shift dimmers, meaning a chopped sine wave,

My criteria for an appropriate phase shift dimmer is one that requires a neutral and has a phase angle trigger point that is essentially independent of load, including no load. These I call a three wire dimmer, and were originally made for dimming a dimmable magnetic ballast fluorescent. These were more than three wires because full voltage had to be available for hearing the fileaments. But the dimmer function only needed three wires. The triggering circuit was always powered from the line to neutral source.

More later.

.

 

[WarrMann]

I tried a Lutron TGCL-153-PH-WH dimmer the client supplied, and got nowhere. It's supposed to be a 1-way / 3-way dimmer depending on how it's hooked up, but all I ever got it to do was toggle on and off - no dimming. It may have been a dodgy dimmer however, as I'm pretty sure the package was open, and I'm pretty sure that there were instructions missing. Is Lutron so low-rent these days as to make you look up the hookup instructions using Google?

Stupid question... are the bulbs dimmable?

I deal with a lot of a-19 LED lamps. Like a literal tonne. The most common reason an a-19 LED won't dim is cause its a non dimmable bulb. That lutron dimmer should have worked just fine, i've used it a bunch. You'll use the common screw, and the one next to it (not above).

You won't find too many single pole LED compatible dimmers, they're almost all going to be single/ 3-way.



Sent from my SM-G950U using Tapatalk

 

[SceneryDriver]

Stupid question... are the bulbs dimmable?

I deal with a lot of a-19 LED lamps. Like a literal shit tonne. The most common reason an a-19 LED won't dim is cause its a non dimmable bulb. That lutron dimmer should have worked just fine, i've used it a bunch. You'll use the common screw, and the one next to it (not above).

You won't find too many single pole LED compatible dimmers, they're almost all going to be single/ 3-way.



Sent from my SM-G950U using Tapatalk

The bulbs are indeed dimmable. Said so right on the package. I believe they were the Home Depot house brand.

The dimmer may have been a dud; like I said before, I seemed like an "open-package." I wired it per the instructions I found on Lutron's website, and got nothing.

Time to try another dimmer later this week when I can get back there. They're using a plain old switch right now. Perhaps that will grow on them.


SceneryDriver

 

[al hildenbrand]

all I ever got it to do was toggle on and off - no dimming. It may have been a dodgy dimmer however, as I'm pretty sure the package was open, and I'm pretty sure that there were instructions missing.

One of the rituals of buying at the orange box store is to make the product selection and then to examine the packaging to find a fresh un-opened blister pack. I've learned this as well.

 

[gar]

190126-1209 EST

SceneryDriver:

The CREE bulb that I have played with is one with vent holes, and I don't really know how to identify it. Listed as 9.8 W, but hard to read. From 2016.

This bulb dims extremrely well down to very low light at dropout at about 13 V with a sine wave.

With a Lutron CTCL-153P dimmer dimming is very good, but not to as low a level as with the Variac. This dimmer is very good and operates as a 2 wire dimmer.

Do some bench testing,

,

 

[SceneryDriver]

By way of a followup:
I installed a Lutron Maestro C-L dimmer. p/n: MACL-153MH-WH

Worked like a dream. Not sure of the make of the LED bulb. The label said "dimmable" and that's all I could see.

Probably helped that I sourced it myself, and made sure the package was sealed before I bought it. Happy client, happy electrician.


SceneryDriver

 

[LarryFine]

Worked like a dream. Not sure of the make of the LED bulb. The label said "dimmable" and that's all I could see.

You serendipitously found a compatible combination. :thumbsup: