On Tue, 12 Aug 2008 22:31:46 -0700, Father Haskell wrote:

High blue output. 15 or 25 watt cool white CFLs make
excellent, inexpensive plant grow lamps. While you
might not like the dead blue spectrum, plants absolutely
flourish under it.

Yes, they do. But they do even better with the 6500K ones. Especially in
an aquarium.

"Mark & Juanita" wrote in message
m...
B A R R Y wrote:


Garage door opener, now that might be a really good application, thanks
for the idea.


We just did a major remodel on our house, garage door openers too. He
asked if we had any lamps, he'd put em in while he was up there. Handed him
a CFL, he said these were great for places with vibration. Much better then
incandescent.

Based on what I have seen in North Carolina with their
little experiment with LED's in stop lights, they
have a ways to go....

Maybe down the road but the current versions are not
up to the task.


Andrew Barss wrote:

I'm hoping for breakthroughs in LED manufacturing, so we can leapfrog over
the CFLs.


-- Andy Barss

Pat Barber wrote:
Based on what I have seen in North Carolina with their
little experiment with LED's in stop lights, they
have a ways to go....

Maybe down the road but the current versions are not
up to the task.

What problem are you seeing? Around here they're being installed on
an attrition basis and seem to be working fine.


Andrew Barss wrote:

I'm hoping for breakthroughs in LED manufacturing, so we can
leapfrog over the CFLs.


-- Andy Barss

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

On Aug 10, 11:40 pm, Robatoy wrote:
On Aug 10, 10:49 pm, Andrew Barss wrote:



Robatoy wrote:

: On Aug 9, 11:28?pm, "Rick Samuel" : wrote:

: What am I missing?
:
: Maybe the dangers of breaking them and releasing mercury into the air.
:
: http://www.snopes.com/medical/toxins/cfl.asp
:
: ?Same with tube type. ?Is there more mercury in CFL's? ?The above said
: nothing about a difference.

: Here's a comparison mercury quantities in different products:

Good to know, but it seems the mercury (as vapor) in CFCs is released
more immediately into the air than in most of the items you listed.

Only if the CFL was hot when broken and the other items cold.

(The air one is breathing while cleaning up a broken CFC).

...

How long do you think mercury vapour stays airborne? The stuff sinks
like a stone.

Wrong.

Mercury liquid and the mercury vapor above it will form an equilibrium
that is temperature dependent. As mercury vapor is removed from
the air above the liquid more will evaporate until all of the liquid
is gone.
While the vapor pressure of mercury is low at room temperature, it is
readily absorbed into the human body by inhalation, and is not nearly
so readily eliminated.

Thus spilt mercury in your environment will continuously accumulate
in the persons who breathe the air in the environment until it is
all removed from that environment.

--

FF

On Aug 11, 4:43 pm, Robatoy wrote:
On Aug 11, 3:49 pm, Andrew Barss wrote:

Robatoy wrote:

: How long do you think mercury vapour stays airborne? The stuff sinks
: like a stone.

Have a look at what you need to do to cleap up a CFL - requires being
down near the floor.

-- Andy Barss

You mean like Pluto the dog, sniffing a trail?
Who puts their face/nose on the floor when they're cleaning? I suspect
in some cases, some spilt Peruvian Marching Powder might compel some
to 'snort the floor'...

Or does mercury 'hover' on your planet? (hint: it's very heavy)

It does indeed 'hover' on my planet. (hint: it has a non-zero vapor
pressure.)

http://www.ilpi.com/msds/ref/vaporpressure.html

http://www.ilpi.com/safety/mercury.html

Lead Oxide also readily volatilises.

--

FF

They started installing them "about" 4-5 years ago
and I have noticed a fairly consistent outage of
the individual "lights" that make up the entire
signal.

Ex: The green light is made up of several leds
and a few will go out after a period of time. I
didn't pay much attention to that until I noticed
that a LOT of the lights had the same issue.

This might have a LOT to do with the vendor that
supplies the lights to the state.

Maybe it's a design feature that keeps the light
going even if there is a partial failure ???


J. Clarke wrote:
Pat Barber wrote:
Based on what I have seen in North Carolina with their
little experiment with LED's in stop lights, they
have a ways to go....

Maybe down the road but the current versions are not
up to the task.

What problem are you seeing? Around here they're being installed on
an attrition basis and seem to be working fine.

Andrew Barss wrote:

I'm hoping for breakthroughs in LED manufacturing, so we can
leapfrog over the CFLs.


-- Andy Barss

Pat Barber wrote:
They started installing them "about" 4-5 years ago
and I have noticed a fairly consistent outage of
the individual "lights" that make up the entire
signal.

Ex: The green light is made up of several leds
and a few will go out after a period of time. I
didn't pay much attention to that until I noticed
that a LOT of the lights had the same issue.

This might have a LOT to do with the vendor that
supplies the lights to the state.

Maybe it's a design feature that keeps the light
going even if there is a partial failure ???

Exactly. A certain percentage of any electronic component will suffer
"infant mortality" (google "bathtub curve" for more information on the
statistical pattern) but with an LED array the failure of a few
individual LEDs doesn't have any significant effect on function.

J. Clarke wrote:
Pat Barber wrote:
Based on what I have seen in North Carolina with their
little experiment with LED's in stop lights, they
have a ways to go....

Maybe down the road but the current versions are not
up to the task.

What problem are you seeing? Around here they're being installed
on
an attrition basis and seem to be working fine.

Andrew Barss wrote:

I'm hoping for breakthroughs in LED manufacturing, so we can
leapfrog over the CFLs.


-- Andy Barss

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

"Rick Samuel" wrote:

We just did a major remodel on our house, garage door openers too.
He asked if we had any lamps, he'd put em in while he was up there.
Handed him a CFL, he said these were great for places with
vibration. Much better then incandescent.

Basic problem with a CFL is that it requires "warm up" time which
makes it a poor choice for fast response On-Off application like
garage door operators.

Better to use a "Rough Service" incandescent lamp.

To qualify as a "rough service" lamp, increase the filament voltage by
say 10% which is exactly what a traffic signal lamp is.(130V vs 120V)

Available at any decent electrical distributor.

Lew

Lew Hodgett wrote:

Basic problem with a CFL is that it requires "warm up" time which
makes it a poor choice for fast response On-Off application like
garage door operators.

Different ones behave differently in this regard. I have some CFLs that
take a minute to come up to full brightness, and others that come up to
near-full-brightness in about a second.

Interestingly, the more expensive ones weren't always better.

Chris

Pat Barber wrote:
Based on what I have seen in North Carolina with their
little experiment with LED's in stop lights, they
have a ways to go....

Maybe down the road but the current versions are not
up to the task.

They've been GREAT here in CT. I'd say we've had them for at least 7-8
years. Did NC pick a crappy supplier?

Also, almost all new aircraft lighting is LED. We replaced our tail
"bubble gum machine" last year with an LED strobe. It wasn't cheap, but
the performance is terrific.

Lew Hodgett wrote:

Basic problem with a CFL is that it requires "warm up" time which
makes it a poor choice for fast response On-Off application like
garage door operators.

Even on 10F temps, mine throws enough light to get in and out of the
car, as well as park the car. It's noticeable but plenty livable.

Lew Hodgett wrote:


"Rick Samuel" wrote:

We just did a major remodel on our house, garage door openers too.
He asked if we had any lamps, he'd put em in while he was up there.
Handed him a CFL, he said these were great for places with
vibration. Much better then incandescent.

Basic problem with a CFL is that it requires "warm up" time which
makes it a poor choice for fast response On-Off application like
garage door operators.


Here in AZ, even in the winter, I'm not sure that will be a problem.
Hasn't been thus far when using the CFL's as porch lights.

Better to use a "Rough Service" incandescent lamp.

To qualify as a "rough service" lamp, increase the filament voltage by
say 10% which is exactly what a traffic signal lamp is.(130V vs 120V)

Available at any decent electrical distributor.

Lew


I've got those in the GDO, my thought was that, in this one case, I might
actually be able to get 60 watts or more of theoretical light from a
fixture that specifies the need for low wattage.


--
If you're going to be dumb, you better be tough

"Mark & Juanita" wrote:

I've got those in the GDO, my thought was that, in this one case, I
might
actually be able to get 60 watts or more of theoretical light from a
fixture that specifies the need for low wattage.

At 1,000 ft, a flying red horse won't see the difference.

Lew

We are talking about state government here...
(lowest bidder)

B A R R Y wrote:

They've been GREAT here in CT. I'd say we've had them for at least 7-8
years. Did NC pick a crappy supplier?

"Lew Hodgett" wrote in message
news:UO%ok.831$ZV1.470@trnddc07...

"Rick Samuel" wrote:

We just did a major remodel on our house, garage door openers too. He
asked if we had any lamps, he'd put em in while he was up there. Handed
him a CFL, he said these were great for places with vibration. Much
better then incandescent.

Basic problem with a CFL is that it requires "warm up" time which makes it
a poor choice for fast response On-Off application like garage door
operators.


No slow warm up, they come on about a 1/2 second after the button is
pushed. May be different in winter, but winter is mild in the TX Hill
Country.

On Sat, 09 Aug 2008 14:10:49 +0300, Rick Samuel wrote:

So, bought a few 42W, 5100K full spectrum, CRI of 82.

Be careful with the term "full spectrum". It is a misleading marketing
term used to advertise many bulbs that are far short of better light.

Technically, CRI (Color Rendering Index) is the accuracy with which a
light matches it's reference, usually daylight. No bulb less than 90
should be called "full spectrum", although many are. (A quick search
finds numerous examples with CRI of 75!)

In short: use bulbs 95 CRI and temperature 5,000-5,5000K for the fullest
and most accurate range of light in the same band as daylight.


--
Steve Hall [ digitect dancingpaper com ]