On Mon, 31 Mar 2008 22:24:44 -0400, Justin
Justin@NobecauseIhatespam.net> wrote:

[snip]

The reason I want to find a dimmable set of CFLs is not energy
efficiency... but PURE laziness. My parents house has a high ceiling
with two recessed dimmable fixtures. They were ahead of their time in
1973, as modern houses are built exactly like this. The problem is, the
lights are 30 feet up, and when one blows my parents call my sorry ass
over for dinner... and pull an "oh yeah there's the light 30 feet up"
you know the story.
So, I want to swap those out with long lasting dimmable CFLs and I never
shop at the Dollar store. For anything. Only once did I go in there in
college to buy some air fresher because I was farting massively. But
that's another story.

Unlike incandescent lamps, dimming CFLs does not increase
their life, and may even shorten it.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.

mroberds@worldnet.att.net> wrote in message
news:eNgIj.101901$Ft5.35182@newsfe15.lga...
Justin <Justin@nobecauseihatespam.net> wrote:
Also, when CFLs fail - what happens?

All of the ones I have had that died of natural causes, mostly GE and
Philips lamps, just didn't light up one day when switched on. One of
them made a popping noise when switched on, but that's about it. I've
also had a few that were murdered by having the glass broken, but there
I just got a loud pop (the same one you get when you break any evacuated
bulb) and then nothing.

Speaking of the GE dimmable.... I bought three of them to put in a ceiling
fan. I am not impressed. You need to turn the dimmer almost all the way up
to get them to light. Then, even after a reasonable warm up, when you turn
the brightness down on them with the dimmer, you get to about half
brightness - dimmer about at 1/4 - and they start flashing like disco
lights. The technology is not quite ready for prime time.

"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:4qs5v31icjt5ucu99i8if9bcmag0d5fqcp@4ax.com...
On Mon, 31 Mar 2008 22:24:44 -0400, Justin
Justin@NobecauseIhatespam.net> wrote:

[snip]

The reason I want to find a dimmable set of CFLs is not energy
efficiency... but PURE laziness. My parents house has a high ceiling
with two recessed dimmable fixtures. They were ahead of their time in
1973, as modern houses are built exactly like this. The problem is, the
lights are 30 feet up, and when one blows my parents call my sorry ass
over for dinner... and pull an "oh yeah there's the light 30 feet up"
you know the story.
So, I want to swap those out with long lasting dimmable CFLs and I never
shop at the Dollar store. For anything. Only once did I go in there in
college to buy some air fresher because I was farting massively. But
that's another story.

Unlike incandescent lamps, dimming CFLs does not increase
their life, and may even shorten it.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.


you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when dimmed,
but certainly not proportionally equal. And in the case of LED products,
this proves even more true.

Willy

If your parents home has 6 inch recessed housings of normal depth (and if
from the 70's, most likely they are fine)... there is a spectacular LED
product that retrofits. In fact, there's literally nothing else like it in
the world today (Okay, I rep it, but it's the truth) as we offer a CRI of
95, consume only 11 watts (some literature says 12, but recent tests
revealed 11)

and has light output similar to a 65 watt R or PAR 30. LED
life BEFORE any visible dimming begins is 50,000 hours, so
in the typical
residence, life expectancy before any dimming begins is 21 years

and the
product could last up to 150,000 hours, although it would most likely be
very dim at that point.

The LR6 (2700 Kelvin) or LR6C (3500 Kelvin) is
fully dimmable, and we recommend Leviton brand dimmers. Check the website
for recommendations.

We sell exclusively through electrical distributors and lighting showrooms.
Check out the website at: www.llfinc.com

Hope that helps.

Willy

"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:iq6sv35af6dos9k7h22q18r7g0895i6anc@4ax.com...
On Wed, 9 Apr 2008 21:13:23 -0400, "Willy"
wesk@prodigy.net> wrote:

you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when dimmed,
but certainly not proportionally equal. And in the case of LED products,
this proves even more true.

What you say with regard to power consumption with dimming
is certainly correct for incandescent lamps, but much less
so for CFLs and LEDs. There is certainly some fixed power
"overhead" in the ballast of any fluorescent lamp, but power
draw comes much closer to following light output than it
does for incandescent lamps.


perhaps I'm misinformed... and will readily admit it if so. I'm wondering
if perhaps the reason you site LED's as closer to proportion (light out put
to electrical consumption) is in reality because of the type of DIMMER being
used?

"Don Klipstein" <don@manx.misty.com> wrote in message
news:slrnfvt4m5.8qd.don@manx.misty.com...

Overall luminous efficacy of a tungsten filament varies greatly with its
temperature. As a result, incandescent lamps have overall luminous
efficacy severely compromised when they are dimmed.

Put 50 watts into a 100 watt 120V A19 incandescent that produces 1710
lumens with 100 watts, and what comes out is about 20% of that 1710
lumens. At half power, overall luminous efficacy is about 40% of that at
full power.

This effect is a characteristic specific to incandescent lamps,
including halogen lamps. Fluorescent lamps and LEDs have overall luminous
efficacy not changing as much as input power is varied.

- Don Klipstein (don@misty.com)

thanks for a great response... information that I'm familiar with, though
probably not backed by the knowledge you have. To continue the conversation
back to the original thought - can you make a similar statement concerning
the luminous efficacy of fluorescents when supplied 50% reduction in
wattage? I often give training seminars that are product related at
electrical distributors, and when this subject hits the floor, I'm somewhat
at a loss to give useful information.

In article <QQdLj.3347$GO4.3027@newssvr19.news.prodigy.net>, Willy wrote:

you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when dimmed,
but certainly not proportionally equal. And in the case of LED products,
this proves even more true.

Most white LEDs operate a little more efficiently when dimmed mildly,
moderately or moderately severely.

I can't say this is always true with the driver circuits however.

- Don Klipstein (don@misty.com)

On Wed, 9 Apr 2008 21:13:23 -0400, "Willy"
wesk@prodigy.net> wrote:

"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:4qs5v31icjt5ucu99i8if9bcmag0d5fqcp@4ax.com...
On Mon, 31 Mar 2008 22:24:44 -0400, Justin
Justin@NobecauseIhatespam.net> wrote:

[snip]

The reason I want to find a dimmable set of CFLs is not energy
efficiency... but PURE laziness. My parents house has a high ceiling
with two recessed dimmable fixtures. They were ahead of their time in
1973, as modern houses are built exactly like this. The problem is, the
lights are 30 feet up, and when one blows my parents call my sorry ass
over for dinner... and pull an "oh yeah there's the light 30 feet up"
you know the story.
So, I want to swap those out with long lasting dimmable CFLs and I never
shop at the Dollar store. For anything. Only once did I go in there in
college to buy some air fresher because I was farting massively. But
that's another story.

Unlike incandescent lamps, dimming CFLs does not increase
their life, and may even shorten it.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.


you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when dimmed,
but certainly not proportionally equal. And in the case of LED products,
this proves even more true.

Willy


What you say with regard to power consumption with dimming
is certainly correct for incandescent lamps, but much less
so for CFLs and LEDs. There is certainly some fixed power
"overhead" in the ballast of any fluorescent lamp, but power
draw comes much closer to following light output than it
does for incandescent lamps.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.

"Bob" <bobsjunkmail@bellsouth.net> wrote in message
news:RtAIj.28248$r76.13513@bignews8.bellsouth.net...

mroberds@worldnet.att.net> wrote in message
news:eNgIj.101901$Ft5.35182@newsfe15.lga...
Justin <Justin@nobecauseihatespam.net> wrote:
Also, when CFLs fail - what happens?

All of the ones I have had that died of natural causes, mostly GE and
Philips lamps, just didn't light up one day when switched on. One of
them made a popping noise when switched on, but that's about it. I've
also had a few that were murdered by having the glass broken, but there
I just got a loud pop (the same one you get when you break any evacuated
bulb) and then nothing.

Speaking of the GE dimmable.... I bought three of them to put in a
ceiling fan. I am not impressed. You need to turn the dimmer almost all
the way up to get them to light. Then, even after a reasonable warm up,
when you turn the brightness down on them with the dimmer, you get to
about half brightness - dimmer about at 1/4 - and they start flashing
like disco lights. The technology is not quite ready for prime time.


Several major manufacturer's of dimmable cfl's are pulling or have pulled
their product from the market because of customer dissatisfaction. The
culprit however, once you move into a quality product such as GE, OSRAM,
SYLVANIA, PHILIPS to name a few, is actually THE DIMMER... not the bulb.
To get maximum dimming, you would find a dimmer rated for electronic or
fluorescent applications (which costs a big more than a standard
incandescent dimmer) would allow you to dim the product more affectively.

Willy

"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:iq6sv35af6dos9k7h22q18r7g0895i6anc@4ax.com...
On Wed, 9 Apr 2008 21:13:23 -0400, "Willy"
wesk@prodigy.net> wrote:

"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:4qs5v31icjt5ucu99i8if9bcmag0d5fqcp@4ax.com...
On Mon, 31 Mar 2008 22:24:44 -0400, Justin
Justin@NobecauseIhatespam.net> wrote:

[snip]

The reason I want to find a dimmable set of CFLs is not energy
efficiency... but PURE laziness. My parents house has a high ceiling
with two recessed dimmable fixtures. They were ahead of their time in
1973, as modern houses are built exactly like this. The problem is, the
lights are 30 feet up, and when one blows my parents call my sorry ass
over for dinner... and pull an "oh yeah there's the light 30 feet up"
you know the story.
So, I want to swap those out with long lasting dimmable CFLs and I never
shop at the Dollar store. For anything. Only once did I go in there in
college to buy some air fresher because I was farting massively. But
that's another story.

Unlike incandescent lamps, dimming CFLs does not increase
their life, and may even shorten it.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.


you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when dimmed,
but certainly not proportionally equal. And in the case of LED products,
this proves even more true.

Willy


What you say with regard to power consumption with dimming
is certainly correct for incandescent lamps, but much less
so for CFLs and LEDs. There is certainly some fixed power
"overhead" in the ballast of any fluorescent lamp, but power
draw comes much closer to following light output than it
does for incandescent lamps.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.


perhaps I'm misinformed... and will readily admit it if so. I'm wondering
if perhaps the reason you site LED's as closer to proportion (light out put
to electrical consumption) is in reality because of the type of DIMMER being
used?

Your thoughts?

Willy

"Willy" <wesk@prodigy.net> wrote in message
news:aVdLj.3376$GO4.2479@newssvr19.news.prodigy.net...
"Bob" <bobsjunkmail@bellsouth.net> wrote in message
news:RtAIj.28248$r76.13513@bignews8.bellsouth.net...

mroberds@worldnet.att.net> wrote in message
news:eNgIj.101901$Ft5.35182@newsfe15.lga...
Justin <Justin@nobecauseihatespam.net> wrote:
Also, when CFLs fail - what happens?

All of the ones I have had that died of natural causes, mostly GE and
Philips lamps, just didn't light up one day when switched on. One of
them made a popping noise when switched on, but that's about it. I've
also had a few that were murdered by having the glass broken, but there
I just got a loud pop (the same one you get when you break any evacuated
bulb) and then nothing.

Speaking of the GE dimmable.... I bought three of them to put in a
ceiling fan. I am not impressed. You need to turn the dimmer almost all
the way up to get them to light. Then, even after a reasonable warm up,
when you turn the brightness down on them with the dimmer, you get to
about half brightness - dimmer about at 1/4 - and they start flashing
like disco lights. The technology is not quite ready for prime time.


Several major manufacturer's of dimmable cfl's are pulling or have pulled
their product from the market because of customer dissatisfaction. The
culprit however, once you move into a quality product such as GE, OSRAM,
SYLVANIA, PHILIPS to name a few, is actually THE DIMMER... not the bulb.
To get maximum dimming, you would find a dimmer rated for electronic or
fluorescent applications (which costs a big more than a standard
incandescent dimmer) would allow you to dim the product more affectively.

Willy



As an afterthought, I should have said, the most LIKELY culprit is the
dimmer - but it is not the exclusive cause of early cut off.

Willy

In article <2_vLj.2480$GE1.1569@nlpi061.nbdc.sbc.com>, Willy wrote:
"Victor Roberts" <xxx@lighting-research.com> wrote in message
news:iq6sv35af6dos9k7h22q18r7g0895i6anc@4ax.com...
On Wed, 9 Apr 2008 21:13:23 -0400, "Willy"
wesk@prodigy.net> wrote:

you are absolutely correct Vic, and furthermore, the public erroneously
believes that there is a direct and proportional electrical savings when
dimming. Actually the amount of electricity consumed is less when
dimmed,
but certainly not proportionally equal. And in the case of LED
products,
this proves even more true.

What you say with regard to power consumption with dimming
is certainly correct for incandescent lamps, but much less
so for CFLs and LEDs. There is certainly some fixed power
"overhead" in the ballast of any fluorescent lamp, but power
draw comes much closer to following light output than it
does for incandescent lamps.


perhaps I'm misinformed... and will readily admit it if so. I'm wondering
if perhaps the reason you site LED's as closer to proportion (light out
put
to electrical consumption) is in reality because of the type of DIMMER
being
used?

Overall luminous efficacy of a tungsten filament varies greatly with its
temperature. As a result, incandescent lamps have overall luminous
efficacy severely compromised when they are dimmed.

Put 50 watts into a 100 watt 120V A19 incandescent that produces 1710
lumens with 100 watts, and what comes out is about 20% of that 1710
lumens. At half power, overall luminous efficacy is about 40% of that at
full power.

This effect is a characteristic specific to incandescent lamps,
including halogen lamps. Fluorescent lamps and LEDs have overall luminous
efficacy not changing as much as input power is varied.

- Don Klipstein (don@misty.com)

On Thu, 10 Apr 2008 17:55:57 -0400, "Willy"
wesk@prodigy.net> wrote:

"Willy" <wesk@prodigy.net> wrote in message
news:aVdLj.3376$GO4.2479@newssvr19.news.prodigy.net...
"Bob" <bobsjunkmail@bellsouth.net> wrote in message
news:RtAIj.28248$r76.13513@bignews8.bellsouth.net...

mroberds@worldnet.att.net> wrote in message
news:eNgIj.101901$Ft5.35182@newsfe15.lga...
Justin <Justin@nobecauseihatespam.net> wrote:
Also, when CFLs fail - what happens?

All of the ones I have had that died of natural causes, mostly GE and
Philips lamps, just didn't light up one day when switched on. One of
them made a popping noise when switched on, but that's about it. I've
also had a few that were murdered by having the glass broken, but
there
I just got a loud pop (the same one you get when you break any
evacuated
bulb) and then nothing.

Speaking of the GE dimmable.... I bought three of them to put in a
ceiling fan. I am not impressed. You need to turn the dimmer almost all
the way up to get them to light. Then, even after a reasonable warm up,
when you turn the brightness down on them with the dimmer, you get to
about half brightness - dimmer about at 1/4 - and they start flashing
like disco lights. The technology is not quite ready for prime time.


Several major manufacturer's of dimmable cfl's are pulling or have
pulled
their product from the market because of customer dissatisfaction. The
culprit however, once you move into a quality product such as GE, OSRAM,
SYLVANIA, PHILIPS to name a few, is actually THE DIMMER... not the
bulb.
To get maximum dimming, you would find a dimmer rated for electronic or
fluorescent applications (which costs a big more than a standard
incandescent dimmer) would allow you to dim the product more
affectively.

Willy



As an afterthought, I should have said, the most LIKELY culprit is the
dimmer - but it is not the exclusive cause of early cut off.

Willy


You are right that the dimmer is not the only issue.

Fluorescent lamps can be dimmed to very low levels, but for
that to happen the ballast must supply a high open circuit
voltage and, most importantly, have a very high Thevenin
impedance looking into the output terminals. (Because the
negative incremental impedance of the discharge gets very
large as the current is decreased, and the output impedance
of the ballast must always be larger than the negative
incremental impedance of the lamp for stable operation.)

No low cost ballasts I know of can meet these requirements.

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.

This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.

In article <UgyLj.789$FF6.42@newssvr29.news.prodigy.net>, Willy wrote:
"Don Klipstein" <don@manx.misty.com> wrote in message
news:slrnfvt4m5.8qd.don@manx.misty.com...

Overall luminous efficacy of a tungsten filament varies greatly with its
temperature. As a result, incandescent lamps have overall luminous
efficacy severely compromised when they are dimmed.

Put 50 watts into a 100 watt 120V A19 incandescent that produces 1710
lumens with 100 watts, and what comes out is about 20% of that 1710
lumens. At half power, overall luminous efficacy is about 40% of that at
full power.

This effect is a characteristic specific to incandescent lamps,
including halogen lamps. Fluorescent lamps and LEDs have overall luminous
efficacy not changing as much as input power is varied.

- Don Klipstein (don@misty.com)

thanks for a great response... information that I'm familiar with, though
probably not backed by the knowledge you have. To continue the conversation
back to the original thought - can you make a similar statement concerning
the luminous efficacy of fluorescents when supplied 50% reduction in
wattage? I often give training seminars that are product related at
electrical distributors, and when this subject hits the floor, I'm somewhat
at a loss to give useful information.

50% power reduction for fluorescents:

Overall luminous efficacy should not change much, and could change in
either direction.

I remember from a few classic books (maybe Waymouth or Elenbaas or
both), and from a fluorescent lamp catalog from the late 1970's that
fluorescent lamps in general, and especially T12 ones, operate slightly
more efficiently when slightly to moderately dimmed - if the shape of the
current waveform stays the same.

There may be some exceptions.

Then comes the question of what happens when the temperature of any
given lamp changes as a result of change in input power, and the mercury
vapor concentration in it changes. The temperature could become closer to
or farther from that at which luminous efficacy is maximized.
Ideally, the lamp's temperature is optimal when the lamp gets full
power, so when power input is reduced enough to make much change in the
lamp temperature and the lamp cools, I would think that its efficiency
should normally decrease slightly. With only slight dimming, the
temperature could easily remain close enough to optimum to have less
effect on efficiency in producing light than the change in current density
within the lamp - so overall luminous efficacy could very slightly
increase.
However, for minor to moderate dimming, I would think that this usually
does not change luminous efficacy much in either direction.

Dimming ballasts may provide extra filament/cathode heating so that the
cathodes do not operate at too low a temperature during dimming. That
would indicate some decrease in overall luminous efficacy from dimming,
since dimming requires an increase in percentage of input power being used
to keep the cathodes hot.

Overall, I would say overall luminous efficacy could make a minor change
in either direction if a fluorescent lamp is operated at half power and
working OK when dimmed to such an extent. And I would not expect the
change to be the same at every installation.

- Don Klipstein (don@misty.com)