Dimmable LED question

[Muse]

So, I've never done this but I have a room or two where I'd like dimmability. If I get, say, a 15 watts dimmable bulb, presumably I need a special switch which I guess has a twist dimming device wired in. If I dial that down to ~2 lumens is the energy consumed approximately equal to the energy consumed by my non-dimmable 2 lumens LEDs? Also, what caveats should I keep in mind when shopping for and/or installing these things? Any hints here appreciated!

 

[MagnusTheBrewer]

Um, one candle is a little over 12 lumens. What would you need less light for?

 

[Muse]

Um, one candle is a little over 12 lumens. What would you need less light for?

I have a few rooms where I like 2-3 lumens. It's enough navigate, i.e. like a night light. But in one of those I want to be able to turn up the lumens once in a while.

 

[dullard]

You need to ask the LED manufacturer which dimmers work with their LEDs. Otherwise if you use a generic dimmer then the dimable LEDs never dim very far (maybe from 100% to 60% brightness). Just getting an LED dimmer switch and a dimmable LED is not enough if you want to go to low lumen levels. Heck, even with a proper match, dimmable LEDs usually don't dim that much but there are a few exceptions.

Dimmable LEDs seriously need an industry standard dimming method.

 

[Aharami]

You need to ask the LED manufacturer which dimmers work with their LEDs. Otherwise if you use a generic dimmer then the dimable LEDs never dim very far (maybe from 100% to 60% brightness). Just getting an LED dimmer switch and a dimmable LED is not enough if you want to go to low lumen levels. Heck, even with a proper match, dimmable LEDs usually don't dim that much but there are a few exceptions.

Dimmable LEDs seriously need an industry standard dimming method.

most dimmable LEDs come with a compatibility list for dimmers

 

[deadlyapp]

More than likely the dimming aspect is done through some sort of variable resistor, so no, the energy consumed is not going to be equal to a 2 lumen LED, but will be likely the same as the higher lumen, or even worse due to efficiency losses through heat.

 

[nakedfrog]

You need to ask the LED manufacturer which dimmers work with their LEDs. Otherwise if you use a generic dimmer then the dimable LEDs never dim very far (maybe from 100% to 60% brightness). Just getting an LED dimmer switch and a dimmable LED is not enough if you want to go to low lumen levels. Heck, even with a proper match, dimmable LEDs usually don't dim that much but there are a few exceptions.

Dimmable LEDs seriously need an industry standard dimming method.

I've put one dimmable LED bulb into an existing fixture with the same dimmer switch that was already in there, and this pretty much matches my experience, it only dims a bit, anything lower on the dimmer and the bulb just turns off.

 

[vi edit]

I put some of these in my basement on a dimmer switch and they are awesome.

http://www.homedepot.com/p/Lithonia...ated-LED-Lighting-Kit-LK5GMW-LED-M4/205210500

Dimmer works very well. It goes from eye blinding bright all the way down to near darkness. The energy use is incredibly minimal. Around 8 watts. You are talking $2-$3 a year at 8 hours a day. Not sure how much more penny pinching you can get.

 

[Red Squirrel]

Most dimmers basically chop up the higher portion of the AC wave, so the device sees a lower average voltage, essentially, but it's a very dirty wave form. I presume any LED bulb that just uses a capacitive dropper will handle it fine, though LED modules themselves do have a certain voltage where they won't light up at all. Breakdown voltage I think it's called?

It should use less power though it depends how efficient the dimmer itself is, some might actually just waste the energy as heat. A variac would be more ideal and probably more efficient, but it's hard to find them in that form factor.

 

[rcpratt]

You mean watts, right? 15 lumens would be almost nothing.

 

[Capt Caveman]

Install some LED night lights around the room.

 

[Muse]

You mean watts, right? 15 lumens would be almost nothing.

Yes, thank you... I changed the OP from 15 lumens to 15 watts.

 

[Muse]

Install some LED night lights around the room.

It's a very old house, over 100 years. I haven't done much to modify the electricity. Most rooms have one overhead light from the ceiling.

I did buy some LED night lights recently, cheap and low wattage. 2 and 3.2 watts from China and off Amazon, respectively. The Chinese bulbs were actually less than a dollar shipped, off Ebay. So far so good, easy on the eyes and pocket book, but occasionally I will want more light.

 

[Stopsignhank]

I just had some dimmable LEDs put in my house. They forgot to install the dimmable switches so I went to Home Depot and got some. They work great. The lights probably go down to 10%. The dimmers are nice because they have a slide on the side of the switch, so you can set the light level to whatever you want and leave it there. Maybe I just got lucky, but they work darn well for me.

 

[Red Squirrel]

It's a very old house, over 100 years. I haven't done much to modify the electricity. Most rooms have one overhead light from the ceiling.

I did buy some LED night lights recently, cheap and low wattage. 2 and 3.2 watts from China and off Amazon, respectively. The Chinese bulbs were actually less than a dollar shipped, off Ebay. So far so good, easy on the eyes and pocket book, but occasionally I will want more light.

I'd avoid electrical stuff from China. Some of it is downright scary in how unsafe it is. Yes the stuff you buy at stores will be from China too, but it has to pass certain certifications like ULC etc. I had bought some grow lights off Amazon and ended up not using them when I saw how unsafe they were. If something like that burns your house down the insurance won't cover it either.

For night light what you could do is get ones that take a C7 bulb and find some retro fit Christmas LED bulbs that fit in it. I imagine it will be under a watt. Get the ones that have the photocell so they only turn on at night.

 

[MtnMan]

I have installed dimmable LEDs throughout the house where I have dimmers that have been there at least 15 years, and it works with all of them. If dimmed far enough, then turned off, they may not turn on again unless you turn the brightness up a bit.

I only buy Feit Electric LEDs, as I have had bad luck with others, including GE. Just don't last as advertised. Costco sells Feit, which makes changing out CF bulbs or Halogen (for dimmable circuits) cost effective.