Where's The LED's?

[Scott Willing]

9300 k I thought the sun was 5500 k

~5600 degrees Kelvin is the standard for mid-day daylight on a clear
day, though I've seen figures more like 6400 as well. "Daylight"
includes sky illumination.

-=Scott the unwelcome pedant

 

[Bob Adkins]

The replacement cost for an LED is much higher, but life is much longer,
meaning fewer or no replacements needed.

By the time an LED fails, the cost will be pennies.

Bob

 

[Bob Adkins]

like tail lights. If you look closely, you will see that many traffic
signals now use LEDs.

And it's about time!

Bob

 

[Bob Adkins]

9300 k I thought the sun was 5500 k

Not today! There's a dark spot on it 10 times bigger than the Earth.

Bob

 

[Bob Adkins]

Unscrew a mag lite or regular flashlight lens to expose the bulb and
compare

No. That's not a standard incandescent or fluorescent. It's OFF TOPIC.

Bob

 

[Bob Adkins]

analogZONE Says . . .

LED-based lighting is gaining popularity because of its long life, power
efficiency, and highly flexible form factor. Where it's practical, compact
fluorescent lights are still the most energy-efficient at 50-75 lumens/Watt,
but at 24 lumens/W, the Luxeon devices are much better than the 12-15
lumens/W offered by standard incandescent bulbs.



Cost? $50 or $.41 / lumen

CF cost? $6 or $.008 / lumen

LED's will soon fulfill the promise that fluorescent broke. Fluorescents
promised to be economical. Well, they are bright for the wattage they use,
but the darn things don't last. Not sure about CF, but standard 48" tubes
last me 6-12 months, and the ballasts last from 6 months to 6 years. I will
be happy if I never see another 48" tube. I have tried the spiral
fluorescent bulbs too. They last from 5 minutes to 5 months. A pack of 5 is
all gone before 6 months. According to the package label, they are supposed
to last for years. Yea, right.

Bob

 

[Bob Adkins]

Very true. Nothing to do with power consumption however.

Everything to do with economy, however.

There's also something to be said for a light actually coming on every time
you flip the switch.

Bob

 

[Bob Adkins]

That is impossible. Laser pointers are, well, lasers.
The vary definition of a laser requires the light
be emitted in very narrow wavelengths.

Why not use red, green, and blue lasers and spin or diffuse the light?

Use your imagination man!

Bob

 

[Bob Adkins]

My info (recalled rather poorly, but I will input it anyway) shows that the
LEDs range from about as efficient as very efficient incandescent bulbs, to
about half as efficient as typical fluorescent bulbs. They are mechanically

This is subject to change daily.

Not that it matters, but LED's are supposed to last 11 years of continuous
use. They will probably be many times brighter and more practical in 2 or 3
years.

If I sound biased toward LED's, it's only because I am. I hate light bulbs
and fluorescent tubes.

Bob

 

[Bob Adkins]

The efficiency of laser diodes is very low compared to LEDs.

I know that. I was just giving you the business.

While not useful for energy saving applications, they could be used in some
very interesting novelty lighting.

Bob

 

[chuck h]

Following link is to a good article about types of lighting, relative
efficiency and other pluses and minuses for each type.

http://www.otherpower.com/otherpower_lighting.html

 

[Gordon Richmond]

Funny,

The tubes just went in the 2-lamp 48" fixture overhead here in my
computer room, not 10 minutes ago. I put that fixture up shortly after
I moved here in 1998. Tubes were new then. I don't think I've changed
out one tube in my workshop since then, either. In my experience, a
5-year life span is closer to the mark.

Gordon Richmond

 

[N9WOS]

LED's will soon fulfill the promise that fluorescent broke. Fluorescents

promised to be economical. Well, they are bright for the wattage they use,
but the darn things don't last. Not sure about CF, but standard 48" tubes
last me 6-12 months, and the ballasts last from 6 months to 6 years. I will
be happy if I never see another 48" tube. I have tried the spiral
fluorescent bulbs too. They last from 5 minutes to 5 months. A pack of 5 is
all gone before 6 months. According to the package label, they are supposed
to last for years. Yea, right.

Bob

Um...... I have had a lot better experience with fluorescent lights.

The main determining factor is the quality of the ballast you are using.
I only run commercial ballast in the fluorescent lights around here.

I got a batch of ballast from a flea market around 5 years ago
The person selling them was a contractor, and he had just
updated all the lights in the building to electronic ballast.
The ballast he took out ranged from 5 to 10 years old, and
some of the newer ones were only a year or so old.
He felt it was just wrong to throw them away so he
brought them to his table at the flee market he rents every year.
He was wanting a dollar a piece for them.
But he would sell the whole batch for 20 bucks if
I would give them a good home.

Stupid me said"ok"
After I got the things home, I found that I had over 150 commercial ballast.
Some of the older ones were magniteck brand.
Most of them are of the "Advance" brand, ranging from normal ones
to energy saver III units.

Now that I look back on it they have returned many times
that 20 bucks in savings
I had spend years fighting those cheep residential ballast.
They would burn out lights in a year or so.
They would be cranky about starting in cold weather.
The ballast would buzz and die at random.

The ones I got are quiet as can be.
Even cheep bulbs will easily last 3 or 4 years.
They start every time.
And I haven't had one ballast die in the 5 years since I got them.
Even though some of them I am running is over 15 years old.

 

[Gerry Schneider]

Not that it matters, but LED's are supposed to last 11 years of continuous
use. They will probably be many times brighter and more practical in 2 or 3
years.

The blue LED structure below the phosphor coating of a "white" LED will still be
shining after 100,000 hours, but the the phosphor coating and epoxy/phosphor
interface will both have photodegraded to uelessness. At full rated current, the
degradation starts at about 1000 hrs and hits about 50% light reduction at 5,000
hrs. This is well known and honestly admitted to by Nichia and other phosphor
white makers, but unfortunately not by the marketing types selling LED
flashlights. I did a product development about a year ago for a client trying to
replace the fluorescent tube of professional quality (auto shop) trouble lights
with an unbreakable white LED stick. He simply would not believe the LED specs
and my initial lab initial test results, and insisted that I build a few working
prototypes. The temp inside the stick went over 100 deg F from the LED (not
ballast) power dissipation, and an array of 100 LEDs was still no comparison to
the light from a 15 watt fluoro tube. A shame when reality bites you in the ass
like that, but hey, it was his money.

Gerry

 

[No One]

The main determining factor is the quality of the ballast you are using.

I only run commercial ballast in the fluorescent lights around here.

Speaking of ballast, our church put in some fluoresent lights a while back
and some of them are 'buzzing'. How do you put a stop to that?

 

[Fred B. McGalliard]

Bolt the iron ballast down tighter. Might work?
My experience. An electronic ballast on a yard area light (the old mercury
kind) flamed and died. Luckily not against the house at the time or the wife
would still be upset. Sitting under a fluorescent with standard ballast at
work, the thing blew up, shot a tiny hole right through the housing and made
a bang like a gunshot.

 

[Steve Spence]

that's conjecture. It's a semiconductor, a diode, and those things have an
intrinsic cost. the price does not change much.

 

[Steve Spence]

you may have power problems. My cf's are over 5 years old and going strong.

 

[N9WOS]

Bolt the iron ballast down tighter. Might work?

My experience. An electronic ballast on a yard area light (the old mercury
kind) flamed and died. Luckily not against the house at the time or the wife
would still be upset. Sitting under a fluorescent with standard ballast at
work, the thing blew up, shot a tiny hole right through the housing and made
a bang like a gunshot.

The statement above sounds backward to me.

Where did you find a mercury vapor light that has an electronic ballast?
It most likely has a standard current limiting transformer.
I don't know of any current model mercury vapor outdoor lights
that have an electronic ballast.

And the fluorescent light that "blew up" sounds like it had
an electronic ballast in it.
The filter capacitors sometimes fail and the result
is the case of the capacitor rupturing.
which sounds like a big BOOM!
The shrapnel from an exploding cap can cause serious injury.

 

[N9WOS]

Speaking of ballast, our church put in some fluoresent lights a while back
and some of them are 'buzzing'. How do you put a stop to that?

Check to make sure that all the hardware is tight.
If that doesn't help........
For a quick fix, loosen the bolt holding the ballast and put a penny
right in the middle of the ballast where it sets against the metal back.
Then tighten the ballast back down.
That puts pressure on the metal underneath the ballast.
that stops it from vibrating.
And it takes any play out of the mounting system.

If the buzzing is coming from inside the ballast and
the light have the small residential ballast in them
that drive two 40W(or so) lights,
then take the cheep ballast out and go to lowes, menards
or what ever home store you have in your area, and
buy some commercial grade ballast that will run the lights.
Residential grade ballast are around 9 and 1/2 inches long.

Most 40W fixtures that have the residential grade ballast
also have the mounting holes to fit a commercial grade ballast.
There is no modification required to make them fit.