Let's shine some light on LED light bulbs

Viseguy said:

I have a table lamp that switches to dim-medium-bright-off just by touching the base. You don't need a 3-way bulb; an ordinary incandescent 40-watter will do. I've bought a couple of equivalent LED bulbs, hoping that they would perform similarly, but they don't. You only get bright or brighter, not dim.

If there's an LED bulb that works in this type of lamp, I'd be thrilled to know about it.

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Did the LED you try state specifically that they could be used with a dimmer?
Some LED's are not compatible.
The touch lamp is essentially a three stage dimmer, so you'd need a dimmable LED.

luvmysuper said:

Did the LED you try state specifically that they could be used with a dimmer?
Some LED's are not compatible.
The touch lamp is essentially a three stage dimmer, so you'd need a dimmable LED.

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<headslap> Ah, of course! I just Googled "dimmable LED" and got a bunch of hits. Thanks so much, Phil!

luvmysuper said:

I purchased these;

http://www.lowes.com/pd_621153-3-75...earch=led+tube+bulb&productId=50297599&rpp=32

SYLVANIA 19-Watt (32W Equivalent) Warm White Linear LED Tube Light Bulb (Common: 48-in; Actual: 50.25-in)
Works with existing instant on ballast.

At $28 bucks, it's about 10 times as expensive as a similar fluorescent, but it has already lasted twice as long as the fluorescents it has replaced, and I expect they will keep on much like the other bulbs I'm using.

Oddly enough, the fluorescent tubes have a stated lifespan of 20,000 hours (the LED tubes are stated at 50,000 hours) but I know for a fact that the fluorescent did NOT last anywhere near that.

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Interesting, my kitchen setup uses eight 36" T8 tubes which are about twice as expensive as 48" ones. They are on dimmers and seem to have about the same lifespan old style incandescent bulbs. These tubes were rated for 3 years @ 6hrs/day (6570 hours total) but don't last anywhere near that long. They must not like being dimmed and start fading quickly. After replacing them all a number of times I am seriously considering if LED tubes will work (need to do more research), or if I will change the whole setup.

The prices continue to drop on LED bulbs. I picked up a few 60W equivalent LED bulbs at the Dollar Tree a couple of weeks ago. So far I am pleased with their performance, light output seems to be pretty close to what the label indicates as far as my naked eye can judge. They are durable, I dropped one 8+ feet into a fiberglass tub and it worked fine. These are non-dimmable "Globe LED for Life" brand.

Gentlemen, thank you for the fast responses. Indeed, as you see there is plenty of evidence that LED is going to be the de facto standard within just a few slight years. How do I know this? Well, I certainly don't have a crystal ball but anecdotally I can tell you what my experience has been the last several years. I work at a facility that probably goes through at least 100,000 dollars worth of lamps, light bulbs or whatever you wish to call them annually. That is likely not an exaggeration. My direct experience with this is that for at least the last five years the quality of fluorescent lamps has gone through the floor. At one time I was removing lamps that were between 5-20 years old depending upon switching cycle and location. Something that comes on and stays on last MUCH longer than something switched all the time. We are now seeing lamp life that is not measured in years or thousands of hours but months. Even the 'good' brands are not immune to this. Some if it is the lowering of mercury(another good reason to ditch fluorescent altogether when you add in recycling costs) which affects brightness and life cycle because it seems to take more energy to light them. This effect is showing across lamp types but most especially the compact 'twister' type lamps to fit regular old medium base lamp holders. Ie; your table lamps, etc. These are complete junk now and I recommend a complete switch over to LED. Just watch the dimmer issue and 3 way lamps. Other than that, it is a no brainer.

Compact pin lamps are another matter. The ruddy things are expensive at anywhere from 4-10 dollars per lamp depending upon brand and wattage. And they don't last nearly as long as they should. They generate a LOT heat at the lamp holder and then there is the typically $25 ballast you need to replace when it goes. There are four pin and two pin models. The four pin lamps are more expensive but work better. The two lamp versions use dirt cheap transformer type ballasts but the lamp bases get super HOT. You cannot touch them after operation for quite awhile after you turn them off or you will be burned if you grab the metal bases. They have the the typical starter you used to see as a round little cartridge that was inserted in special socket in older linear fixtures. It is simply built into the lamp base in two pin models. Right now our facilities are looking into LED replacements for both two and four pin fixtures(typically can lights or wall sconce) that will simply plug in and use the existing ballast. The results in early use have not been to good. Flickering and other issues. We'll see. For now, try the linear lamps and the medium base LEDs. Let the market sort your pin light models over the next year or two.

For me, since moving to my place in December 2012, I only replaced one LED lamp twice and it's the one over the stove. I ended up putting a fluorescent bulb and it's been working well so far.

StillShaving said:

Interesting, my kitchen setup uses eight 36" T8 tubes which are about twice as expensive as 48" ones. They are on dimmers and seem to have about the same lifespan old style incandescent bulbs. These tubes were rated for 3 years @ 6hrs/day (6570 hours total) but don't last anywhere near that long. They must not like being dimmed and start fading quickly. After replacing them all a number of times I am seriously considering if LED tubes will work (need to do more research), or if I will change the whole setup.

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I had three lamps underneath my counters, but had a spot for four. I had ordered some cheap T8s, but they didn't last but a few days before going dim. I ended up getting some dimmable LED fixtures from Lowes. I changed the switch out to a dimmer, then direct wired four of these fixtures together. At the lowest setting the LEDs are brighter than the original T8s were, plus the cabinets don't get hot inside like they did before. The four fixtures ended up costing around $250, but if they last the twenty years they're rated for, it will be well worth it.

The only thing not LED in my house now is a fluorescent over our kitchen sink , one over the clothes washer and dryer and a bunch of hanging 48" fixtures in my garage shop. About a year ago I found some 8w LED globe bulbs for our bathroom fixture that had used 8 40 watt bulbs. So went from 320 watts to 64. These are the large round globes which are totally exposed in a strip type fixture. The only thing is that the brightness is so intense you do now want to look directly at the bulb, other than that overall light level is much better. These are Feit bulbs, and I searched quit a bit to find decent prices and finally bought 20 off an ebay vendor. Two bathrooms at 8 bulbs each plus 4 extra.

luvmysuper said:

I purchased these;

http://www.lowes.com/pd_621153-3-75...earch=led+tube+bulb&productId=50297599&rpp=32

SYLVANIA 19-Watt (32W Equivalent) Warm White Linear LED Tube Light Bulb (Common: 48-in; Actual: 50.25-in)
Works with existing instant on ballast.

At $28 bucks, it's about 10 times as expensive as a similar fluorescent, but it has already lasted twice as long as the fluorescents it has replaced, and I expect they will keep on much like the other bulbs I'm using.

Oddly enough, the fluorescent tubes have a stated lifespan of 20,000 hours (the LED tubes are stated at 50,000 hours) but I know for a fact that the fluorescent did NOT last anywhere near that.

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When I was five years old, my Uncle's dry cleaning store on Ludlow St (down the block from Katz's Deli) had two rows of fluorescent lights. He would turn one set off at night to conserve electricity, while the other row was lit continuously. He complained that the lights he would turn off had to be replaced regularly, while he almost never had to replace a bulb that was always on, some lasting a decade. Without any understanding of electricity whatsoever, I quickly surmised that is was the cycling on and off that was responsible for this. It's not magic. Why do incandescent bulbs only blow out when you turn them on? You'll hardly ever see one blow out while it's on. (The resistivity of the metal filament increases with temperature. When the bulb is off, it's cooler, so the initial current surge will be higher.)

Different types of bulbs are better suited for different tasks. We happen to be in a great age for lighting, and efficiency is the name of the game. With an average cost per kilowatt-hour of roughly 12 cents, running a device continuously costs very nearly a buck per watt per year. Leave that 100W bulb on in the basement all year, and it will cost you a hundred bucks. Mom was right!

ouch said:

With an average cost per kilowatt-hour of roughly 12 cents, running a device continuously costs very nearly a buck per watt per year. Leave that 100W bulb on in the basement all year, and it will cost you a hundred bucks. Mom was right!

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At the college where I work, in 2010 there was a big project to put in automatic motion-sensing light switches. In offices where the lights need to remain on all day and are responsibly shut off at the end of the day, these switches were put in and people would have to get up from their desk and wave their arms around. In basements and attics where people rarely go, the old switches and incandescent bulbs remained. Whenever I go into one of those basements I encounter lights left on.

In the server room where I sometimes spend a half hour or more sitting behind a large cabinet elbow-deep in dozens of cables the lights would shut off just as I was approaching a critical moment and I'd need to undo everything, extract myself, and wave the lights back on. I did that twice before I took matters into my own hands...I looked up that stupid sensor's wiring manual and rewired it to stay always on. I never forget to shut off the manual switch on my way out.

I wonder how many thousands of dollars per year are wasted on those basements/attics, and how many tens of thousands were wasted putting motion sensors in the wrong places.

I took a flier yesterday and bought four of these dimmable 40-watt equivalent LEDs. They shipped today. I'll let you know how they work in my 3-way lamp.

Viseguy said:

I took a flier yesterday and bought four of these dimmable 40-watt equivalent LEDs. They shipped today. I'll let you know how they work in my 3-way lamp.

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Keep us posted!
Worst case scenario, you can use them around the house and save a few bucks.
That's a pretty reasonable price for an LED bulb.

luvmysuper said:

Did the LED you try state specifically that they could be used with a dimmer?
Some LED's are not compatible.
The touch lamp is essentially a three stage dimmer, so you'd need a dimmable LED.

Click to expand...

There is caveat to this, and I seriously doubt it can be made to work properly. The electronics in most older dimmer (that use active components like the capacity sensors) depend on leakage current "through the tungston filaments" to work.

This isn't enough current - mere milliamps - to make an incandescent bulb light. But it's enough to slightly excite the LEDs. hence the "off" state actually produces quite a bit of light if the room is dark.

mrb7 said:

There is caveat to this, and I seriously doubt it can be made to work properly. The electronics in most older dimmer (that use active components like the capacity sensors) depend on leakage current "through the tungston filaments" to work.

This isn't enough current - mere milliamps - to make an incandescent bulb light. But it's enough to slightly excite the LEDs. hence the "off" state actually produces quite a bit of light if the room is dark.

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Thanks, good information!

incandescent going for 105 years:

Seraphim said:

incandescent going for 105 years:

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"Don't touch that switch!!!"

luvmysuper said:

Thanks, good information!

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If somewhat depressing in my case. Fingers crossed....

luvmysuper said:

Keep us posted!
Worst case scenario, you can use them around the house and save a few bucks.
That's a pretty reasonable price for an LED bulb.

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True, true.

I've been slowly replacing the lights in my ceiling fans with led lights. Due to the fan's vibration, they last far longer than filament bulbs, and give a brighter light.

Seraphim said:

incandescent going for 105 years:

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They didn't have a power outage in over a century?

Viseguy said:

If somewhat depressing in my case. Fingers crossed....

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Well, it's certainly worth giving a shot. It might work fine. And as someone else pointed out, the bulb will still be good somewhere else.

Although the technology was pretty stable for decades, in the past few decades it's been changing rapidly.