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What's different between Dimmable and non-dimmable LED bulbs

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Jerr...@spamblocked.com

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Oct 22, 2015, 3:35:00 PM10/22/15
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I've noticed that the stores sell both regular (non-dimmable) and
Dimmable LED bulbs. The dimmable ones are more expensive. What is
different inside of them?

I dont use dimmers, or I'd try this.

What happens if a regular bulb is connected to a dimmer?

I'd assume a dimmable bulb will work fine on a circuit without a dimmer,
or is there a reason to NOT use them if no dimmer exists? (other than
the extra cost).


FrozenNorth

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Oct 22, 2015, 3:58:28 PM10/22/15
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My wife hates the CFL bulbs, they give her headaches so while they were
still available we got two cases of 24 60W incandescent, rated for 130V,
not one has failed and it has been over a year. Sure they are a bit
less bright than a regular 60W/120V bulb, but it keeps her happy,
haven't tried the LED ones yet, they still seem rather expensive last I
looked.

--
Froz...

Quando omni flunkus, moritati

cl...@snyder.on.ca

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Oct 22, 2015, 4:39:45 PM10/22/15
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A non dimmable lamp has a simpler "driver" circuit for the LEDs that
regulates the current to the leds without reference to voltage.

If you put them on a dimmer they will dim a little bit, then start to
flash and then if you keep dimming - shut off.

Dimmables work just fine without a dimmer - and I'd guess it won't be
long untill the price difference between the two is so small only the
crappiest LED products will be available as non-dimmable.

gfre...@aol.com

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Oct 22, 2015, 5:00:08 PM10/22/15
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130v bulbs are still available.
I agree there is nothing like the light from an incandescent,
particularly when you dim them.
LEDs and CFLs may "dim" but the color stays the same.
I suppose they will come up with color shifting LEDs since white is
actually RGB and they could use a smart controller to change the blue
balance but I haven't seen them yet.


Don Y

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Oct 22, 2015, 5:16:23 PM10/22/15
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[I suspect the post was refering to "a regular *LED* bulb" in a dimmer
circuit]

We use "commercial grade (130V) incandescent floods/spots in most of
our area lighting, here. Dimmable CFL's and even dimmable LED's just
don't have the same dynamic range nor the nice warm color that a
glowing piece of wire has!

They tend to have a thicker filament and, because they are running a bit
cooler than their ratings (e.g., at 130V, power is 130*130/K whereas
it's roughly 120*120/K when operated at actual line voltage; about 15%
less)

With very little street lighting and other external light sources,
many nights are delightfully dark, here. So, even with the curtains
OPEN, the house is pitch black at night -- or some portion of each
night.

If we turn the overhead floods on at the lowest dimmer setting,
the rooms, floors and furnishings are all pleasantly visible
to "recently opened" eyes (that are not keen on the harsh bright
lights that you'd normally encounter -- even from a dimmable!).

So, when guests visit, we leave most of the house illuminated in this
manner overnight. Easier than risking a visitor unfamiliar with the
house "falling" into the sunken living room, etc. And, much less
"tacky" than having a boatload of "nightlights" cluttering up the
space!

The "adjustable color" LEDs would be an interesting choice -- but
for their cost and the technology they embody.

Percival P. Cassidy

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Oct 22, 2015, 5:58:55 PM10/22/15
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Why would I *want* a bulb that changes color? I often want less light
but not orange light.

The color change in incandescent bubs when they are dimmed is an
unavoidable side-effect -- and in my opinion an undesirable side-effect.

Perce

Stormin Mormon

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Oct 22, 2015, 6:08:50 PM10/22/15
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On 10/22/2015 3:58 PM, FrozenNorth wrote:
> My wife hates the CFL bulbs, they give her headaches so while they were
> still available we got two cases of 24 60W incandescent, rated for 130V,
> not one has failed and it has been over a year. Sure they are a bit
> less bright than a regular 60W/120V bulb, but it keeps her happy,
> haven't tried the LED ones yet, they still seem rather expensive last I
> looked.
>

Dollar Tree has filament bulbs, 60, 75,
and 100 watts. I've not tried them, so
can't comment on quality or life.

--
.
Christopher A. Young
learn more about Jesus
. www.lds.org
.
.

cl...@snyder.on.ca

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Oct 22, 2015, 6:18:51 PM10/22/15
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White in many cases now are NOT RGB, but white phosphor, just like on
a flourescent tube. Colour temperature is determined by the phosphor
used.

Steve Stone

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Oct 22, 2015, 7:07:55 PM10/22/15
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On 10/22/2015 3:34 PM, Jerr...@spamblocked.com wrote:
> I've noticed that the stores sell both regular (non-dimmable) and
> Dimmable LED bulbs. The dimmable ones are more expensive. What is
> different inside of them?

I've found that CREE dimmable LED bulbs work with Intermatic light
timers that pass a low voltage thru the bulb when the timer turns off.
These are in the wall timers that are marked incandescent only. Sure
there is a slight glow on the bulbs when they are off but it sure beats
digging up the driveway and front lawn to rewire the lamp post or spend
a hundred dollars on a new LED lamp post head.

gfre...@aol.com

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Oct 22, 2015, 7:24:20 PM10/22/15
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To each his own.
I guess the whole idea of dinner by candle light just seems silly to
you. I bet you would walk around my house with a flashlight ... a
great big one.

gfre...@aol.com

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Oct 22, 2015, 7:25:14 PM10/22/15
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LEDs?

Percival P. Cassidy

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Oct 22, 2015, 8:00:06 PM10/22/15
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> To each his own.
> I guess the whole idea of dinner by candle light just seems silly to
> you. I bet you would walk around my house with a flashlight ... a
> great big one.

When we want dinner by candle light, we light candles.

Perce

Jerr...@spamblocked.com

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Oct 22, 2015, 9:35:26 PM10/22/15
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What kind if timer is that? Whats the point of sending a low voltage to
the bulb other than to waste electricity?
The old mechanical timers simply turned off/on a switch. You must be
referring to a digital timer. But I still dont see the reason to send
that low voltage.

You should not need to dig the lawn up, just get a different timer. It
sounds to me that yours is defective.

cl...@snyder.on.ca

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Oct 22, 2015, 10:55:24 PM10/22/15
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Yes. White LEDs. The existence of blue LEDs and high-efficiency LEDs
quickly led to the development of the first white LED, which employed
a Y 3Al 5O 12:Ce, or "YAG", phosphor coating to mix down-converted
yellow light with blue to produce light that appears white.

cl...@snyder.on.ca

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Oct 22, 2015, 10:57:13 PM10/22/15
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Nope, not defective. They are 2 wire timers or switches - the current
to run the solid state timer is soursed through the bulb. No bulb, no
timer (or no remote switch)

gfre...@aol.com

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Oct 22, 2015, 11:34:40 PM10/22/15
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On Thu, 22 Oct 2015 20:34:52 -0500, Jerr...@spamblocked.com wrote:

Those are used where you do not have a neutral available.
The neutral is derived through the load. The code now requires a
neutral it switch locations with a few exceptions. It is basically
where you can add one later without disturbing the building finish.

The 2 wire timers and occupancy sensors work fine with an
incandescent. There is no real net waste since that current would be
going down the neutral anyway.

It is a MA or less but the capacitors in a LED or CFL will store that
up and make them flash acting as a relaxation oscillator.

gfre...@aol.com

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Oct 22, 2015, 11:41:19 PM10/22/15
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Yellow is R/G
What happens to the color when you reduce the drive to the blue LED?

HerHusband

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Oct 23, 2015, 12:09:26 AM10/23/15
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> I agree there is nothing like the light from an incandescent,
> particularly when you dim them.
> LEDs and CFLs may "dim" but the color stays the same.
> I suppose they will come up with color shifting LEDs

Color changing LED's are already available.

I like the 60W Philips Warm Glow bulbs. They're a nice warm white at full
brightness, but take on a very natural orange/yellow hue when dimmed. The
result is very close to a traditional incandescent bulb, but uses about
one sixth the power.

You can find them at Home Depot for about $10, or online from places like
Amazon:

http://www.amazon.com/Philips-455840-Equivalent-2200K-2700K-
Dimmable/dp/B00TZEB0Q0

Sylvania makes a similar "sunset effect" LED bulb (Lowes sells them), but
I think the Philips bulbs look and perform better.

I have been a big fan of CREE LED's for a while now, but their dimmable
LED bulbs stay white when dimmed. The effect just looks weird, probably
due to a lifetime of experience with incandescent bulbs.


Unfortunately, the bulb is only half the equation. The dimmable bulbs
work OK with a basic manual dimmer, but most won't dim properly with an
electronic dimmer. The dimmer expects a certain load and the bulb will
often stay lit at a low level even at the lowest dimmer setting.

Thankfully, new dimmers are now available that dim the new LED's
perfectly. I just replaced my old dimmers with Lutron's Caseta wireless
dimmer:

http://www.amazon.com/Lutron-P-PKG1W-WH-Wireless-600-watt-Multi-
Location/dp/B00JJY0S4G

I can now dim the three wall sconces in our living room just like the old
incandescent bulbs. They're actually brighter than the old 60W bulbs and
still have that nice warm glow when dimmed. 30 watts instead of 180
watts, longer life, and they don't put off any heat.

I also like that LED's are full brightness when turned on (like an
incandescent). CFL's can take a few minutes to come up to full
brightness, especially when it's cold.

Also, since the LED's put off very little heat, I can safely install 75
LED replacements in fixtures that are only rated for 60 watt bulbs. It
helps give a little more light to rooms that tend to be a little dark.

Anthony Watson
www.mountainsoftware.com
www.watsondiy.com

mako...@yahoo.com

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Oct 23, 2015, 9:50:05 AM10/23/15
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> >>
> >> Why would I *want* a bulb that changes color? I often want less light
> >> but not orange light.
> >>
> >> The color change in incandescent bubs when they are dimmed is an
> >> unavoidable side-effect -- and in my opinion an undesirable side-effect.
>

So what is the "right color" for a light to always be in your opinion?

Even the sun turns red as it sets


Mark

cl...@snyder.on.ca

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Oct 23, 2015, 1:11:23 PM10/23/15
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The colour temperature changes a bit untill the light goes out It is
only one LED - - -

gfre...@aol.com

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Oct 23, 2015, 1:24:50 PM10/23/15
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Hence the problem for people who like the color shift when you dim an
incandescent.

Steve Stone

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Oct 23, 2015, 2:46:35 PM10/23/15
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On 10/22/2015 9:34 PM, Jerr...@spamblocked.com wrote:

>
> What kind if timer is that? Whats the point of sending a low voltage to
> the bulb other than to waste electricity?

http://www.intermatic.com/en/products/timers/inwalltimers/electronic_timers/ej351

•Up to 48 ON/OFF events per day
•No neutral required
•Self learning, repeats first 24 hour ON/OFF pattern if not programmed
•"Random" setting turns light ON and OFF at slightly different times
each day
•15 minute memory guard protects against power failure


EJ351 Single Pole 120 VAC, 60 Hz 40-500 Watts
Incandescent
For use with Standard or Decorator Style Switch Plate
4 3/16" H x 1 3/4" W x 2" D 32ºF to 104ºF (0ºC to 40ºC) 1 Year

gregz

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Oct 24, 2015, 3:10:29 AM10/24/15
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Dimmable LEDs lower the current through the led gradually. Non types try to
maintain current. A dimmable can be made cheaper than non.

Greg
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