B
Bret Cahill
Guest
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
flicker.
Bret Cahill
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John Larkin
Guest
On Wed, 24 Mar 2010 17:06:18 -0700 (PDT), Bret Cahill
<BretCahill@peoplepc.com> wrote:
John
<BretCahill@peoplepc.com> wrote:
Subtracting cycles?Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
John
D
David Eather
Guest
On 25/03/2010 10:16 AM, John Larkin wrote:
On Wed, 24 Mar 2010 17:06:18 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
John
MOC3041 + triac + variable duty cycle pulse train perhaps?
P
petrus bitbyter
Guest
"David Eather" <eather@tpg.com.au> schreef in bericht
news:wo-dnV1AQs8-3jbWnZ2dnUVZ_tyrnZ2d@supernews.com...
Don't think so. Using phase control the tube will not ignite below a certain
voltage. As that limit is not sharply defined and there will always be some
noise on the mains the tube starts to flicker.
petrus bitbyter
news:wo-dnV1AQs8-3jbWnZ2dnUVZ_tyrnZ2d@supernews.com...
On 25/03/2010 10:16 AM, John Larkin wrote:
On Wed, 24 Mar 2010 17:06:18 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
John
MOC3041 + triac + variable duty cycle pulse train perhaps?
Don't think so. Using phase control the tube will not ignite below a certain
voltage. As that limit is not sharply defined and there will always be some
noise on the mains the tube starts to flicker.
petrus bitbyter
J
John Larkin
Guest
On Thu, 25 Mar 2010 08:43:39 -0700 (PDT), Bret Cahill
<BretCahill@peoplepc.com> wrote:
reasons. They are used for heaters and such. AC lighting dimmers are
usually triac phase control, and most CFs don't like that. Some do.
There are high-frequency electronic dimmers that sort of simulate a
variac. Most CFs don't like them either.
When a dimming function is integrated into the lamp or fixture, all
sorts of electronic tricks become possible.
John
<BretCahill@peoplepc.com> wrote:
Which converts 100/120 Hz flicker to 50/60.Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Cycle-skipping controllers aren't used for lighting for obviousLighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
reasons. They are used for heaters and such. AC lighting dimmers are
usually triac phase control, and most CFs don't like that. Some do.
There are high-frequency electronic dimmers that sort of simulate a
variac. Most CFs don't like them either.
When a dimming function is integrated into the lamp or fixture, all
sorts of electronic tricks become possible.
John
B
Bret Cahill
Guest
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
B
Bret Cahill
Guest
If you have to restart more often than the start up time it may not beJust start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
John
MOC3041 + triac + variable duty cycle pulse train perhaps?
Don't think so. Using phase control the tube will not ignite below a certain
voltage. As that limit is not sharply defined and there will always be some
noise on the mains the tube starts to flicker.
easy.
A night light works for just waking around but if you are looking for
some small item and don't want to be permanently awakened by bright
light you need a dimmer.
See how long it takes me to find something that might not be cost
effective in the USPTO.
Bret Cahill
J
John Fields
Guest
On Thu, 25 Mar 2010 08:43:39 -0700 (PDT), Bret Cahill
<BretCahill@peoplepc.com> wrote:
No. In the case of conventional fluorescent lamps operating from 60Hz
mains, they flash 120 times per second because the positive-going as
well as the negative-going excursions of the 60Hz mains are used to
cause the lamp to re-ignite once it has been extinguished by crossing
zero.
"Subtracting cycles" then refers to causing one or more of the igniting
waveforms to be bypassed, resulting in an apparent dimming of the lamp.
---
Half-wave rectifier, don't you mean?
Either way, you don't know what you're talking about.
---
More crap.
JF
<BretCahill@peoplepc.com> wrote:
---Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
No. In the case of conventional fluorescent lamps operating from 60Hz
mains, they flash 120 times per second because the positive-going as
well as the negative-going excursions of the 60Hz mains are used to
cause the lamp to re-ignite once it has been extinguished by crossing
zero.
"Subtracting cycles" then refers to causing one or more of the igniting
waveforms to be bypassed, resulting in an apparent dimming of the lamp.
---
---Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Half-wave rectifier, don't you mean?
Either way, you don't know what you're talking about.
---
---Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
More crap.
JF
D
David Eather
Guest
On 25/03/2010 10:46 PM, petrus bitbyter wrote:
coupler. This would work as the OP suggested - by subtracting mains
cycles e.g. 4 cycles on 1 cycle off or 3 cycles on 2 cycles off.
Would it work to dim a CF bulb. I don't know, but I don't think so.
No, not phase control. The MOC3041 is a zero crossing triac opto"David Eather"<eather@tpg.com.au> schreef in bericht
news:wo-dnV1AQs8-3jbWnZ2dnUVZ_tyrnZ2d@supernews.com...
On 25/03/2010 10:16 AM, John Larkin wrote:
On Wed, 24 Mar 2010 17:06:18 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
John
MOC3041 + triac + variable duty cycle pulse train perhaps?
Don't think so. Using phase control the tube will not ignite below a certain
voltage. As that limit is not sharply defined and there will always be some
noise on the mains the tube starts to flicker.
petrus bitbyter
coupler. This would work as the OP suggested - by subtracting mains
cycles e.g. 4 cycles on 1 cycle off or 3 cycles on 2 cycles off.
Would it work to dim a CF bulb. I don't know, but I don't think so.
D
David Eather
Guest
On 26/03/2010 2:15 AM, John Larkin wrote:
of) out of discretes so I could better control a space heater and
decided I must have been mad to do something so useless.
http://www.filedropper.com/missingcycles
AC lighting dimmers are
I didn't know such things existed. I designed one the other day (sortOn Thu, 25 Mar 2010 08:43:39 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Which converts 100/120 Hz flicker to 50/60.
Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
Cycle-skipping controllers aren't used for lighting for obvious
reasons. They are used for heaters and such.
of) out of discretes so I could better control a space heater and
decided I must have been mad to do something so useless.
http://www.filedropper.com/missingcycles
AC lighting dimmers are
usually triac phase control, and most CFs don't like that. Some do.
There are high-frequency electronic dimmers that sort of simulate a
variac. Most CFs don't like them either.
When a dimming function is integrated into the lamp or fixture, all
sorts of electronic tricks become possible.
John
P
petrus bitbyter
Guest
"David Eather" <eather@tpg.com.au> schreef in bericht
news:B_CdnZCuHfDdeDbWnZ2dnUVZ_tOdnZ2d@supernews.com...
flicker below 60-70%. This method is definitively not the way to dim lights.
A CLF may do slightly better as there is a rectifier and a bufferelco build
in. Nevertheless I cannot imagine the flicker starts only at 40% when
subtracting cycles. For a phase controlled triac it is much more likely.
petrus bitbyter
news:B_CdnZCuHfDdeDbWnZ2dnUVZ_tOdnZ2d@supernews.com...
Ever build a heat controller like that. Even an incandescent bulb started toOn 25/03/2010 10:46 PM, petrus bitbyter wrote:
"David Eather"<eather@tpg.com.au> schreef in bericht
news:wo-dnV1AQs8-3jbWnZ2dnUVZ_tyrnZ2d@supernews.com...
On 25/03/2010 10:16 AM, John Larkin wrote:
On Wed, 24 Mar 2010 17:06:18 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
John
MOC3041 + triac + variable duty cycle pulse train perhaps?
Don't think so. Using phase control the tube will not ignite below a
certain
voltage. As that limit is not sharply defined and there will always be
some
noise on the mains the tube starts to flicker.
petrus bitbyter
No, not phase control. The MOC3041 is a zero crossing triac opto coupler.
This would work as the OP suggested - by subtracting mains cycles e.g. 4
cycles on 1 cycle off or 3 cycles on 2 cycles off.
Would it work to dim a CF bulb. I don't know, but I don't think so.
flicker below 60-70%. This method is definitively not the way to dim lights.
A CLF may do slightly better as there is a rectifier and a bufferelco build
in. Nevertheless I cannot imagine the flicker starts only at 40% when
subtracting cycles. For a phase controlled triac it is much more likely.
petrus bitbyter
J
John Larkin
Guest
On Fri, 26 Mar 2010 08:41:29 +1000, David Eather <eather@tpg.com.au>
wrote:
Zero-crossing triac controller chips have been around for a long time.
They dole out integral bursts of AC line cycles. Heaters like
restauarant deep-fat friers use these. EMI and magnetic-acoustic noise
are low and there's no DC component to saturate distribution
transformers.
There is debate about the meaning of "power factor" into a resistive
load driven by these gadgets.
John
wrote:
On 26/03/2010 2:15 AM, John Larkin wrote:
On Thu, 25 Mar 2010 08:43:39 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Which converts 100/120 Hz flicker to 50/60.
Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
Cycle-skipping controllers aren't used for lighting for obvious
reasons. They are used for heaters and such.
I didn't know such things existed. I designed one the other day (sort
of) out of discretes so I could better control a space heater and
decided I must have been mad to do something so useless.
http://www.filedropper.com/missingcycles
Zero-crossing triac controller chips have been around for a long time.
They dole out integral bursts of AC line cycles. Heaters like
restauarant deep-fat friers use these. EMI and magnetic-acoustic noise
are low and there's no DC component to saturate distribution
transformers.
There is debate about the meaning of "power factor" into a resistive
load driven by these gadgets.
John
J
John Larkin
Guest
On Thu, 25 Mar 2010 20:49:56 -0700 (PDT), Bret Cahill
<BretCahill@peoplepc.com> wrote:
John
<BretCahill@peoplepc.com> wrote:
Only if the AC supply voltage is low. LEDs don't like to be zenered.Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Or maybe the LED itself is a half bridge rectifier.
John
D
David Eather
Guest
On 26/03/2010 11:07 AM, John Larkin wrote:
(one day I went to bed, 12 years later I woke up and half the
semiconductor manufacturers I knew no longer existed and Motorola just
made telephones!) I just didn't think people would use them that way - I
thought a thermostat and EMI filter would be the go.
I knew about the controller chips. They existed before I went to "sleep"On Fri, 26 Mar 2010 08:41:29 +1000, David Eather<eather@tpg.com.au
wrote:
On 26/03/2010 2:15 AM, John Larkin wrote:
On Thu, 25 Mar 2010 08:43:39 -0700 (PDT), Bret Cahill
BretCahill@peoplepc.com> wrote:
Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Which converts 100/120 Hz flicker to 50/60.
Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
Cycle-skipping controllers aren't used for lighting for obvious
reasons. They are used for heaters and such.
I didn't know such things existed. I designed one the other day (sort
of) out of discretes so I could better control a space heater and
decided I must have been mad to do something so useless.
http://www.filedropper.com/missingcycles
Zero-crossing triac controller chips have been around for a long time.
They dole out integral bursts of AC line cycles. Heaters like
restauarant deep-fat friers use these. EMI and magnetic-acoustic noise
are low and there's no DC component to saturate distribution
transformers.
(one day I went to bed, 12 years later I woke up and half the
semiconductor manufacturers I knew no longer existed and Motorola just
made telephones!) I just didn't think people would use them that way - I
thought a thermostat and EMI filter would be the go.
There is debate about the meaning of "power factor" into a resistive
load driven by these gadgets.
John
B
Bret Cahill
Guest
Or maybe the LED itself is a half bridge rectifier.Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
It probably gets irritating below 30.Which converts 100/120 Hz flicker to 50/60.
Yea! That's the right term!Lighting still requires a significant amount of power but it will be
pain free reducing this cost.
Bret Cahill
Cycle-skipping
I saw some ads on Google.controllers aren't used for lighting for obvious
reasons. They are used for heaters and such. AC lighting dimmers are
usually triac phase control, and most CFs don't like that. Some do.
There are high-frequency electronic dimmers that sort of simulate a
variac. Most CFs don't like them either.
When a dimming function is integrated into the lamp or fixture, all
sorts of electronic tricks become possible.
Is anything at Home Depot?
Bret Cahill
B
Bret Cahill
Guest
You can take out the blue LED from a dollar store night light and wireJust start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Or maybe the LED itself is a half bridge rectifier.
Only if the AC supply voltage is low. LEDs don't like to be zenered.
up 4 - 6 whiteish LED Christmas lights and then hot melt glue the
string to the wall.
I'm guessing the power consumption is still about 1/4 watt -- not
worth turning off.
I have very little credibility in interior design. You'd have to get
some personality like Martha Stewart to get it to sell.
Bret Cahill
B
Bob Masta
Guest
On Fri, 26 Mar 2010 00:05:37 +0100, "petrus
bitbyter"
<pieterkraltlaatditweg@enditookhccnet.nl> wrote:
I built a kiln controller using a zero-crossing
triac optocoupler, and at low duty cycles you
could see flicker in other incandescent lights in
the house!
Best regards,
Bob Masta
DAQARTA v5.10
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
Frequency Counter, FREE Signal Generator
Pitch Track, Pitch-to-MIDI
DaqMusic - FREE MUSIC, Forever!
(Some assembly required)
Science (and fun!) with your sound card!
bitbyter"
<pieterkraltlaatditweg@enditookhccnet.nl> wrote:
"David Eather" <eather@tpg.com.au> schreef in bericht
news:B_CdnZCuHfDdeDbWnZ2dnUVZ_tOdnZ2d@supernews.com...
No, not phase control. The MOC3041 is a zero crossing triac opto coupler.
This would work as the OP suggested - by subtracting mains cycles e.g. 4
cycles on 1 cycle off or 3 cycles on 2 cycles off.
Would it work to dim a CF bulb. I don't know, but I don't think so.
Ever build a heat controller like that. Even an incandescent bulb started to
flicker below 60-70%. This method is definitively not the way to dim lights.
snip
I built a kiln controller using a zero-crossing
triac optocoupler, and at low duty cycles you
could see flicker in other incandescent lights in
the house!
Best regards,
Bob Masta
DAQARTA v5.10
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
Frequency Counter, FREE Signal Generator
Pitch Track, Pitch-to-MIDI
DaqMusic - FREE MUSIC, Forever!
(Some assembly required)
Science (and fun!) with your sound card!
J
John Fields
Guest
On Thu, 25 Mar 2010 21:38:28 -0700 (PDT), Bret Cahill
<BretCahill@peoplepc.com> wrote:
Half _wave_ rectifier
---
Mmmm. stylish...
---
Hmmm...
In one breath you demand green, and then in the second you say that
wasting 1/4 watt is unimportant.
For someone who pretends to be interested in the "big picture" it seems
you've lost sight of the fact that if one hundred million of those
widgets were to be left on all the time and they were dissipating 1/4
watt each, they'd dissipate 25 megawatts, of which 12.5MW would be
wasted if the illumination was only needed for an average of 12 hours.
So there's 12.5MW up in smoke...
Then there's the matter of keeping the magic smoke _inside_ the LEDs,
which will be difficult since, as Larkin pointed out, LEDs don't like to
be Zenered.
One way to fix that problem is to configure the LEDs as two series
strings connected in parallel opposition, like this: (View in Courier)
120AC>---[R]--+-[LED>]---[LED>]---[LED>]-+
| |
+-[<LED]---[<LED]---[<LED]-+
|
120AC>-----------------------------------+
That way, the OFF LEDs only see the Vf of the ON LEDs instead of the
entire mains peak voltage across them.
I'd use 6 LEDs total to keep everything symmetrical, and then, since
only 3 LEDs would be on at a time they'd dissipate:
10.5V * 0.02A
P = --------------- = 0.105 watts
2
and for both strings that would be 0.210 watts, pretty close to your 1/4
watt guess.
The series current limiting resistor also has to be considered if the
kluge is going to live past the first mains cycle in, and its value will
be:
Vmains - Vled 120V - 10.5V
R = --------------- = -------------- = 5475 ohms
Iled 0.02A
Unfortunately, it'll dissipate:
P = I˛R = 0.02˛A * 5475 ohms = 2.19 watts,
so there's a whopping 219 MEGAwatts wasted as heat.
Assume then that these kluges will only need to be on about half the
time, on average, and the waste will be about 116 megawatts if they're
left on all the time.
---
With as little credibility as you have, period, I doubt whether _anyone_
would want to besmirch their good name by having it associated with the
likes of you.
JF
<BretCahill@peoplepc.com> wrote:
---Just start subtracting cycles. Below 25% - 40% power it'll start to
flicker.
Bret Cahill
Subtracting cycles?
Instead of flashing 60 or 120 Hz it only flashes 30 or 60 cycles/sec.
Eventually everyone will go to LED which is easy to operate at half
power: add a half bridge rectifier.
Or maybe the LED itself is a half bridge rectifier.
Half _wave_ rectifier
---
---Only if the AC supply voltage is low. LEDs don't like to be zenered.
You can take out the blue LED from a dollar store night light and wire
up 4 - 6 whiteish LED Christmas lights and then hot melt glue the
string to the wall.
Mmmm. stylish...
---
---I'm guessing the power consumption is still about 1/4 watt -- not
worth turning off.
Hmmm...
In one breath you demand green, and then in the second you say that
wasting 1/4 watt is unimportant.
For someone who pretends to be interested in the "big picture" it seems
you've lost sight of the fact that if one hundred million of those
widgets were to be left on all the time and they were dissipating 1/4
watt each, they'd dissipate 25 megawatts, of which 12.5MW would be
wasted if the illumination was only needed for an average of 12 hours.
So there's 12.5MW up in smoke...
Then there's the matter of keeping the magic smoke _inside_ the LEDs,
which will be difficult since, as Larkin pointed out, LEDs don't like to
be Zenered.
One way to fix that problem is to configure the LEDs as two series
strings connected in parallel opposition, like this: (View in Courier)
120AC>---[R]--+-[LED>]---[LED>]---[LED>]-+
| |
+-[<LED]---[<LED]---[<LED]-+
|
120AC>-----------------------------------+
That way, the OFF LEDs only see the Vf of the ON LEDs instead of the
entire mains peak voltage across them.
I'd use 6 LEDs total to keep everything symmetrical, and then, since
only 3 LEDs would be on at a time they'd dissipate:
10.5V * 0.02A
P = --------------- = 0.105 watts
2
and for both strings that would be 0.210 watts, pretty close to your 1/4
watt guess.
The series current limiting resistor also has to be considered if the
kluge is going to live past the first mains cycle in, and its value will
be:
Vmains - Vled 120V - 10.5V
R = --------------- = -------------- = 5475 ohms
Iled 0.02A
Unfortunately, it'll dissipate:
P = I˛R = 0.02˛A * 5475 ohms = 2.19 watts,
so there's a whopping 219 MEGAwatts wasted as heat.
Assume then that these kluges will only need to be on about half the
time, on average, and the waste will be about 116 megawatts if they're
left on all the time.
---
---I have very little credibility in interior design. You'd have to get
some personality like Martha Stewart to get it to sell.
With as little credibility as you have, period, I doubt whether _anyone_
would want to besmirch their good name by having it associated with the
likes of you.
JF