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Kill LED lamp flicker
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Mike Monett VE3BTI
Sep 8, 2023, 4:10:49 AM9/8/23
to
I recently changed the overhead fluorescent lamps for LED replacements.
Very soon, I noticed they were flickering a lot more the the old
fluorescents.
They flicker on the slightest line disturbance, from someone turning on a
microwave to who knows what outside the building. It turns out the
bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
the spying business, but not good in the shop.
I studied various methods of supplying clean power, from LifePO4 batteries
to my own solar array. Very expensive, and can't avoid batteries.
I settled on a brute force attack, using a dimmer and huge capacitors. The
dimmer is needed as a PWM to reduce the rectified line voltage from 160
volts down to 125 volts. The dimmer also allows to dim the LEDs to arrive
at a more comfortable illumination. They are very bright.
The lED lamps contain their own bridge rectifier to convert the AC line
voltage to DC to drive the lamps.
There is one trick in the circuit that is of note, and is why I am posting
the circuit here.
It is necessary to break the dimmer AC line between the delay pot and the
triac to insert a 10 ohm resistor. The resistor cuts down on the surge
current during startup, but it causes a drop in line voltage. If this drop
is applied to the delay pot, the circuit goes haywire during startup.
Note the 1N4007 diodes are replaced by a regular bridge rectifier with
suitable ratings. It is easier to model using 1N4007s than trying to find a
bridge rectifier in LTspice.
The circuit has been tested on LTspice IV and XII. I will never run QSpice
since is requires MS 10-11 and 64 bits. I got off the Microsoft merry-go-
round at Win7, and I am perfectly content to stay there.
From past experience it may be necessary to fiddle with the Model
statements to get the program to load in LTspice. The line wrap in the
newsgroup creates havoc on LTspice.
Here's the ASC file:
Version 4
SHEET 1 1684 680
WIRE 176 16 -16 16
WIRE 224 16 176 16
WIRE 368 16 304 16
WIRE 432 16 368 16
WIRE 480 16 432 16
WIRE 592 16 544 16
WIRE 368 32 368 16
WIRE 176 64 176 16
WIRE -16 112 -16 16
WIRE 368 128 368 112
WIRE 464 128 368 128
WIRE 480 128 464 128
WIRE 592 128 592 16
WIRE 592 128 544 128
WIRE 624 128 592 128
WIRE 640 128 624 128
WIRE 656 128 640 128
WIRE 752 128 736 128
WIRE 864 128 752 128
WIRE 368 144 368 128
WIRE 640 160 640 128
WIRE 864 160 864 128
WIRE 752 176 752 128
WIRE 176 208 176 144
WIRE 224 208 176 208
WIRE 256 208 224 208
WIRE 176 224 176 208
WIRE 432 272 432 16
WIRE 480 272 432 272
WIRE 592 272 544 272
WIRE 640 272 640 240
WIRE 640 272 592 272
WIRE 720 272 640 272
WIRE 752 272 752 240
WIRE 752 272 720 272
WIRE 864 272 864 240
WIRE 864 272 752 272
WIRE -16 304 -16 192
WIRE 176 304 176 288
WIRE 176 304 -16 304
WIRE 368 304 368 208
WIRE 368 304 176 304
WIRE -16 320 -16 304
WIRE 464 352 464 128
WIRE 480 352 464 352
WIRE 592 352 592 272
WIRE 592 352 544 352
FLAG -16 320 0
FLAG 368 16 A
FLAG 224 208 VC1
FLAG 752 128 C
FLAG 720 272 D
FLAG 368 128 B
FLAG 624 128 E
SYMBOL misc\\DIAC 320 176 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 64 32 VTop 2
WINDOW 123 92 32 VTop 2
SYMATTR InstName Q1
SYMATTR Value2 VK=30
SYMBOL voltage -16 96 R0
WINDOW 0 10 -1 Left 2
WINDOW 3 -65 137 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value SINE(0 166 60 0 0 0 20)
SYMBOL res 160 160 M180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R1
SYMATTR Value 200k
SYMBOL cap 160 224 R0
SYMATTR InstName C1
SYMATTR Value .062u
SYMBOL misc\\TRIAC 336 144 R0
SYMATTR InstName U1
SYMBOL diode 544 0 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D1
SYMATTR Value 1N4007
SYMBOL diode 544 112 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D2
SYMATTR Value 1N4007
SYMBOL diode 480 288 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D3
SYMATTR Value 1N4007
SYMBOL diode 480 368 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D4
SYMATTR Value 1N4007
SYMBOL res 624 144 R0
SYMATTR InstName R2
SYMATTR Value 230
SYMBOL cap 736 176 R0
SYMATTR InstName C2
SYMATTR Value 1640uf
SYMBOL res 752 112 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 0.1
SYMBOL res 352 16 R0
SYMATTR InstName R4
SYMATTR Value 1k
SYMBOL res 320 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R5
SYMATTR Value 10
SYMBOL res 848 144 R0
SYMATTR InstName R6
SYMATTR Value 100k
TEXT 40 -48 Left 2 !.tran 0 500ms 0 10u
TEXT -376 280 Left 2 !.subckt DIAC T1 T2\n* default parameters\n.param RS=
10 ; series resistance\n.param VK=20 ; breakdown voltage\nQ1 N002 N001 T2 0
PN\nQ2 N001 N002 N005 0 NP\nR1 N002 N004 {20K*(VK-1)}\nR2 N004 T2 9.5K\nR3
N002 N005 9.5K\nQ3 N004 N003 N005 0 PN\nQ4 N003 N004 T2 0 NP\nR4 T1 N005
{RS}\n.model PN NPN Cjc=10p Cje=10p\n.model NP PNP Cjc=10p Cje=10p\n.ends
DIAC
TEXT -376 16 Left 2 !.subckt TRIAC MT2 G MT1\n.param R=10K\nQ1 N001 G MT1 0
NP\nQ2 N001 N002 MT2 0 NP\nQ3 N002 N001 MT1 0 PN\nQ4 G N001 MT2 0 PN\nR1
MT2 N002 {R}\nR2 G MT1 {R}\n.model PN NPN Cjc=10p Cje=10p\n.model NP PNP
Cjc=10p Cje=10p\n.ends TRIAC
TEXT 40 -80 Left 2 ;'DIAC TRIAC Light Dimmer Step RDim
TEXT 64 336 Left 2 ;200e3*.062e-6 = 0.0124 seconds
TEXT -56 432 Left 2 !.model 1N4007 D(Is=14.11n N=1.984 Rs=33.89m Ikf=94.81
Xti=3 Eg=1.11 Cjo=25.89p \n+M=.44 Vj=.3245 Fc=.5 Bv=1500 Ibv=10u Tt=5.7u
Iave=1A Vpk=1500 mfg=Motorola type=silicon)
TEXT 632 312 Left 2 ;100e3*1540e-6= 154 seconds
The PLT file
[Transient Analysis]
{
Npanes: 2
Active Pane: 1
{
traces: 3 {524293,0,"V(d,c)"} {524294,0,"V(d,e)"} {34603012,1,"I
(R3)"}
X: ('m',0,0,0.05,0.5)
Y[0]: (' ',0,0,10,130)
Y[1]: (' ',0,-4,2,22)
Volts: (' ',0,0,0,0,10,130)
Amps: (' ',0,0,0,-4,2,22)
Log: 0 0 0
GridStyle: 1
},
{
traces: 2 {524291,0,"V(b)"} {524290,0,"V(a)"}
X: ('m',0,0,0.05,0.5)
Y[0]: (' ',0,-180,30,180)
Y[1]: (' ',0,1e+308,3,-1e+308)
Volts: (' ',0,0,0,-180,30,180)
Log: 0 0 0
GridStyle: 1
}
}
--
MRM
Very soon, I noticed they were flickering a lot more the the old
fluorescents.
They flicker on the slightest line disturbance, from someone turning on a
microwave to who knows what outside the building. It turns out the
bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
the spying business, but not good in the shop.
I studied various methods of supplying clean power, from LifePO4 batteries
to my own solar array. Very expensive, and can't avoid batteries.
I settled on a brute force attack, using a dimmer and huge capacitors. The
dimmer is needed as a PWM to reduce the rectified line voltage from 160
volts down to 125 volts. The dimmer also allows to dim the LEDs to arrive
at a more comfortable illumination. They are very bright.
The lED lamps contain their own bridge rectifier to convert the AC line
voltage to DC to drive the lamps.
There is one trick in the circuit that is of note, and is why I am posting
the circuit here.
It is necessary to break the dimmer AC line between the delay pot and the
triac to insert a 10 ohm resistor. The resistor cuts down on the surge
current during startup, but it causes a drop in line voltage. If this drop
is applied to the delay pot, the circuit goes haywire during startup.
Note the 1N4007 diodes are replaced by a regular bridge rectifier with
suitable ratings. It is easier to model using 1N4007s than trying to find a
bridge rectifier in LTspice.
The circuit has been tested on LTspice IV and XII. I will never run QSpice
since is requires MS 10-11 and 64 bits. I got off the Microsoft merry-go-
round at Win7, and I am perfectly content to stay there.
From past experience it may be necessary to fiddle with the Model
statements to get the program to load in LTspice. The line wrap in the
newsgroup creates havoc on LTspice.
Here's the ASC file:
Version 4
SHEET 1 1684 680
WIRE 176 16 -16 16
WIRE 224 16 176 16
WIRE 368 16 304 16
WIRE 432 16 368 16
WIRE 480 16 432 16
WIRE 592 16 544 16
WIRE 368 32 368 16
WIRE 176 64 176 16
WIRE -16 112 -16 16
WIRE 368 128 368 112
WIRE 464 128 368 128
WIRE 480 128 464 128
WIRE 592 128 592 16
WIRE 592 128 544 128
WIRE 624 128 592 128
WIRE 640 128 624 128
WIRE 656 128 640 128
WIRE 752 128 736 128
WIRE 864 128 752 128
WIRE 368 144 368 128
WIRE 640 160 640 128
WIRE 864 160 864 128
WIRE 752 176 752 128
WIRE 176 208 176 144
WIRE 224 208 176 208
WIRE 256 208 224 208
WIRE 176 224 176 208
WIRE 432 272 432 16
WIRE 480 272 432 272
WIRE 592 272 544 272
WIRE 640 272 640 240
WIRE 640 272 592 272
WIRE 720 272 640 272
WIRE 752 272 752 240
WIRE 752 272 720 272
WIRE 864 272 864 240
WIRE 864 272 752 272
WIRE -16 304 -16 192
WIRE 176 304 176 288
WIRE 176 304 -16 304
WIRE 368 304 368 208
WIRE 368 304 176 304
WIRE -16 320 -16 304
WIRE 464 352 464 128
WIRE 480 352 464 352
WIRE 592 352 592 272
WIRE 592 352 544 352
FLAG -16 320 0
FLAG 368 16 A
FLAG 224 208 VC1
FLAG 752 128 C
FLAG 720 272 D
FLAG 368 128 B
FLAG 624 128 E
SYMBOL misc\\DIAC 320 176 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 64 32 VTop 2
WINDOW 123 92 32 VTop 2
SYMATTR InstName Q1
SYMATTR Value2 VK=30
SYMBOL voltage -16 96 R0
WINDOW 0 10 -1 Left 2
WINDOW 3 -65 137 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value SINE(0 166 60 0 0 0 20)
SYMBOL res 160 160 M180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R1
SYMATTR Value 200k
SYMBOL cap 160 224 R0
SYMATTR InstName C1
SYMATTR Value .062u
SYMBOL misc\\TRIAC 336 144 R0
SYMATTR InstName U1
SYMBOL diode 544 0 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D1
SYMATTR Value 1N4007
SYMBOL diode 544 112 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D2
SYMATTR Value 1N4007
SYMBOL diode 480 288 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D3
SYMATTR Value 1N4007
SYMBOL diode 480 368 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D4
SYMATTR Value 1N4007
SYMBOL res 624 144 R0
SYMATTR InstName R2
SYMATTR Value 230
SYMBOL cap 736 176 R0
SYMATTR InstName C2
SYMATTR Value 1640uf
SYMBOL res 752 112 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 0.1
SYMBOL res 352 16 R0
SYMATTR InstName R4
SYMATTR Value 1k
SYMBOL res 320 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R5
SYMATTR Value 10
SYMBOL res 848 144 R0
SYMATTR InstName R6
SYMATTR Value 100k
TEXT 40 -48 Left 2 !.tran 0 500ms 0 10u
TEXT -376 280 Left 2 !.subckt DIAC T1 T2\n* default parameters\n.param RS=
10 ; series resistance\n.param VK=20 ; breakdown voltage\nQ1 N002 N001 T2 0
PN\nQ2 N001 N002 N005 0 NP\nR1 N002 N004 {20K*(VK-1)}\nR2 N004 T2 9.5K\nR3
N002 N005 9.5K\nQ3 N004 N003 N005 0 PN\nQ4 N003 N004 T2 0 NP\nR4 T1 N005
{RS}\n.model PN NPN Cjc=10p Cje=10p\n.model NP PNP Cjc=10p Cje=10p\n.ends
DIAC
TEXT -376 16 Left 2 !.subckt TRIAC MT2 G MT1\n.param R=10K\nQ1 N001 G MT1 0
NP\nQ2 N001 N002 MT2 0 NP\nQ3 N002 N001 MT1 0 PN\nQ4 G N001 MT2 0 PN\nR1
MT2 N002 {R}\nR2 G MT1 {R}\n.model PN NPN Cjc=10p Cje=10p\n.model NP PNP
Cjc=10p Cje=10p\n.ends TRIAC
TEXT 40 -80 Left 2 ;'DIAC TRIAC Light Dimmer Step RDim
TEXT 64 336 Left 2 ;200e3*.062e-6 = 0.0124 seconds
TEXT -56 432 Left 2 !.model 1N4007 D(Is=14.11n N=1.984 Rs=33.89m Ikf=94.81
Xti=3 Eg=1.11 Cjo=25.89p \n+M=.44 Vj=.3245 Fc=.5 Bv=1500 Ibv=10u Tt=5.7u
Iave=1A Vpk=1500 mfg=Motorola type=silicon)
TEXT 632 312 Left 2 ;100e3*1540e-6= 154 seconds
The PLT file
[Transient Analysis]
{
Npanes: 2
Active Pane: 1
{
traces: 3 {524293,0,"V(d,c)"} {524294,0,"V(d,e)"} {34603012,1,"I
(R3)"}
X: ('m',0,0,0.05,0.5)
Y[0]: (' ',0,0,10,130)
Y[1]: (' ',0,-4,2,22)
Volts: (' ',0,0,0,0,10,130)
Amps: (' ',0,0,0,-4,2,22)
Log: 0 0 0
GridStyle: 1
},
{
traces: 2 {524291,0,"V(b)"} {524290,0,"V(a)"}
X: ('m',0,0,0.05,0.5)
Y[0]: (' ',0,-180,30,180)
Y[1]: (' ',0,1e+308,3,-1e+308)
Volts: (' ',0,0,0,-180,30,180)
Log: 0 0 0
GridStyle: 1
}
}
--
MRM
piglet
Sep 8, 2023, 6:18:48 AM9/8/23
to
piglet
piglet
Sep 8, 2023, 6:37:58 AM9/8/23
to
with one of the 600V types included with LTSpice then the crazy currents
disappear and the circuit does more as you describe. Have you checked
Pdiss in R4?
piglet
Don Y
Sep 8, 2023, 6:56:39 AM9/8/23
to
On 9/8/2023 1:10 AM, Mike Monett VE3BTI wrote:
> I recently changed the overhead fluorescent lamps for LED replacements.
>
> Very soon, I noticed they were flickering a lot more the the old
> fluorescents.
Use a dimmer designed for LED lighting. They will typically
> I recently changed the overhead fluorescent lamps for LED replacements.
>
> Very soon, I noticed they were flickering a lot more the the old
> fluorescents.
also have a "dimmer low end" than conventional dimmers.
LEDs that flicker on a simple switched line are probably of
poor quality.
Ricky
Sep 8, 2023, 8:26:30 AM9/8/23
to
On Friday, September 8, 2023 at 6:56:39 AM UTC-4, Don Y wrote:
> On 9/8/2023 1:10 AM, Mike Monett VE3BTI wrote:
> > I recently changed the overhead fluorescent lamps for LED replacements.
> >
> > Very soon, I noticed they were flickering a lot more the the old
> > fluorescents.
> Use a dimmer designed for LED lighting. They will typically
> also have a "dimmer low end" than conventional dimmers.
> LEDs that flicker on a simple switched line are probably of
> poor quality.
I bought an LED lighting fixture and the dimmer specified on the package as compatible. It wasn't. It was all crap. I contacted the manufacturer and their response was to return the product. They don't care. They sell you gold on the box, but crap in it.
> On 9/8/2023 1:10 AM, Mike Monett VE3BTI wrote:
> > I recently changed the overhead fluorescent lamps for LED replacements.
> >
> > Very soon, I noticed they were flickering a lot more the the old
> > fluorescents.
> Use a dimmer designed for LED lighting. They will typically
> also have a "dimmer low end" than conventional dimmers.
> LEDs that flicker on a simple switched line are probably of
> poor quality.
--
Rick C.
- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209
John Larkin
Sep 8, 2023, 11:25:43 AM9/8/23
to
On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
<spa...@not.com> wrote:
>I recently changed the overhead fluorescent lamps for LED replacements.
>
>Very soon, I noticed they were flickering a lot more the the old
>fluorescents.
>
>They flicker on the slightest line disturbance, from someone turning on a
>microwave to who knows what outside the building. It turns out the
>bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>the spying business, but not good in the shop.
I doubt that the fluorescents are much slower, at visual speeds, than
<spa...@not.com> wrote:
>I recently changed the overhead fluorescent lamps for LED replacements.
>
>Very soon, I noticed they were flickering a lot more the the old
>fluorescents.
>
>They flicker on the slightest line disturbance, from someone turning on a
>microwave to who knows what outside the building. It turns out the
>bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>the spying business, but not good in the shop.
LEDs. You can verify that with a photodetector and an ocilloscope.
Maybe you have cheap flourescent-replacement tubes.
legg
Sep 8, 2023, 11:54:30 AM9/8/23
to
>I recently changed the overhead fluorescent lamps for LED replacements.
>
>Very soon, I noticed they were flickering a lot more the the old
>fluorescents.
>
<snip>
>
>Very soon, I noticed they were flickering a lot more the the old
>fluorescents.
>
>The lED lamps contain their own bridge rectifier to convert the AC line
>voltage to DC to drive the lamps.
>
<snip>
>voltage to DC to drive the lamps.
>
Mike, there are many fluorescent replacement types of LED lamp.
At this low (and usually fixed) power level, it's possible to
skin this cat any number of ways.
If you use a variac to evaluate brightness vs line voltage on
the lamps you are using, you'll see the range of voltages
required to perform the dimming function.
I think you'll be surprised at just how low these voltage
values can be and how narrow the adjustment range is.
Only types that are designed for dimming, or dimmers
designed for LEDs can give you satisfactory performance.
R4 . . . . this is one cat that isn't skinned properly.
RL
Mike Monett VE3BTI
Sep 8, 2023, 2:49:57 PM9/8/23
to
legg <le...@nospam.magma.ca> wrote:
> <snip>
>>The lED lamps contain their own bridge rectifier to convert the AC line
>>voltage to DC to drive the lamps.
>>
> <snip>
>
> Mike, there are many fluorescent replacement types of LED lamp.
> At this low (and usually fixed) power level, it's possible to
> skin this cat any number of ways.
>
> If you use a variac to evaluate brightness vs line voltage on
> the lamps you are using, you'll see the range of voltages
> required to perform the dimming function.
>
> I think you'll be surprised at just how low these voltage
> values can be and how narrow the adjustment range is.
> Only types that are designed for dimming, or dimmers
> designed for LEDs can give you satisfactory performance.
>
> R4 . . . . this is one cat that isn't skinned properly.
>
> RL
Thanks for your message.
> <snip>
>>The lED lamps contain their own bridge rectifier to convert the AC line
>>voltage to DC to drive the lamps.
>>
> <snip>
>
> Mike, there are many fluorescent replacement types of LED lamp.
> At this low (and usually fixed) power level, it's possible to
> skin this cat any number of ways.
>
> If you use a variac to evaluate brightness vs line voltage on
> the lamps you are using, you'll see the range of voltages
> required to perform the dimming function.
>
> I think you'll be surprised at just how low these voltage
> values can be and how narrow the adjustment range is.
> Only types that are designed for dimming, or dimmers
> designed for LEDs can give you satisfactory performance.
>
> R4 . . . . this is one cat that isn't skinned properly.
>
> RL
I am interested in eliminating flicker due to line transients. A capacitor
stores energy and supplies it to the LED during a transient.
Ordinary dimmers are not intended to drive capacitors. This will be the
first time. I will have to see how they perform but I am pretty confident
they will work in this application.
I am not interested in actually dimming the light. I have a 0 - 300v supply
that I can use to see how the LED lamps perform with DC. I understand they
operate over a narrow range, much like a diode, as they are basically
current driven.
I agree with you. R4 may not be needed. I included it as I didn't know how
it would affect the operation of the circuit. Changing it to 1e6 ohms made
no difference.
--
MRM
Lasse Langwadt Christensen
Sep 8, 2023, 3:07:32 PM9/8/23
to
brightness at any voltage high enough for the LEDs and regulation
or that they have a capacitive dropper that will only work on DC and have a terrible power factor
Mike Monett VE3BTI
Sep 8, 2023, 3:10:36 PM9/8/23
to
piglet <erichp...@hotmail.com> wrote:
>
> The model you used for 1N4007 has something very wrong - if I replace
> with one of the 600V types included with LTSpice then the crazy currents
> disappear and the circuit does more as you describe. Have you checked
> Pdiss in R4?
>
> piglet
VII doesn't have the 1N4007, so I got the model from LTspice IV. It shows a
>
> The model you used for 1N4007 has something very wrong - if I replace
> with one of the 600V types included with LTSpice then the crazy currents
> disappear and the circuit does more as you describe. Have you checked
> Pdiss in R4?
>
> piglet
PIV of 1,500 v. There are no 600 V versions in IV.
I see no crazy currents in IV or VII. Can you tell me more about what you are
seeing?
I tried to plot the power in R4 but had no luck in IV or VII. I tried to
calculate pwr(V(x), V(a)) but got 9.65e+307 with no units. So I have to
guess. I'll try a 2W wirewound.
--
MRM
Mike Monett VE3BTI
Sep 8, 2023, 3:12:32 PM9/8/23
to
piglet <erichp...@hotmail.com> wrote:
> What do you use the waste heat in R5 for, boiling water for tea?
>
> piglet
>
I don't think it's that bad. Futher answer in next post.
> What do you use the waste heat in R5 for, boiling water for tea?
>
> piglet
>
--
MRM
Mike Monett VE3BTI
Sep 8, 2023, 3:29:18 PM9/8/23
to
Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
> most LED lamps have a build in constant current driver so they will be
> the same brightness at any voltage high enough for the LEDs and
> regulation
>
> or that they have a capacitive dropper that will only work on DC and
> have a terrible power factor
I checked. The only electronics on my LED lamps is a bridge rectifier.
> most LED lamps have a build in constant current driver so they will be
> the same brightness at any voltage high enough for the LEDs and
> regulation
>
> or that they have a capacitive dropper that will only work on DC and
> have a terrible power factor
A capacitive dropper will not work on DC.
--
MRM
Lasse Langwadt Christensen
Sep 8, 2023, 4:07:16 PM9/8/23
to
Mike Monett VE3BTI
Sep 8, 2023, 8:24:36 PM9/8/23
to
Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
> fredag den 8. september 2023 kl. 21.29.18 UTC+2 skrev Mike Monett VE3BTI:
>> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>
>> > most LED lamps have a build in constant current driver so they will be
>> > the same brightness at any voltage high enough for the LEDs and
>> > regulation
>> >
>> > or that they have a capacitive dropper that will only work on DC and
>> > have a terrible power factor
>> I checked. The only electronics on my LED lamps is a bridge rectifier.
>>
>> A capacitive dropper will not work on DC.
>
> obviously meant "only work on AC"
Why do you want to drop the voltage? There are the correct number of LEDs
> fredag den 8. september 2023 kl. 21.29.18 UTC+2 skrev Mike Monett VE3BTI:
>> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>
>> > most LED lamps have a build in constant current driver so they will be
>> > the same brightness at any voltage high enough for the LEDs and
>> > regulation
>> >
>> > or that they have a capacitive dropper that will only work on DC and
>> > have a terrible power factor
>> I checked. The only electronics on my LED lamps is a bridge rectifier.
>>
>> A capacitive dropper will not work on DC.
>
> obviously meant "only work on AC"
in series needed to work at 120VAC.
I verified there is a bridge rectifier in the LED lamps. I found a web site
that disassembled a LED lamp and read the part number off the IC mounted on
a small pcb. It turned out to be a bridge rectifier.
The bridge rectifier in the LED lamps is needed to convert the AC line
voltage to rectified DC as the LEDS cannot run with reversed polarity.
There is no need for a constant current driver and none is installed.
Obviously, the LED lamps are sensitive to line voltage since they flicker
with slight disturbances in the line voltage.
If a constant current driver was installed, there would be no flickering
and no need for energy storage to ride out the transients.
--
MRM
whit3rd
Sep 9, 2023, 5:10:57 AM9/9/23
to
current limiters passing AC); the ballast limits the current, the rectifiers
steer it so both half-cycles of the AC power the LEDs. There's
maximal (100 or 120 Hz) flicker, but at those frequencies, only
video cameras catch it as flicker.
Martin Brown
Sep 9, 2023, 5:25:45 AM9/9/23
to
On 09/09/2023 01:24, Mike Monett VE3BTI wrote:
> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>
>> fredag den 8. september 2023 kl. 21.29.18 UTC+2 skrev Mike Monett VE3BTI:
>>> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>>
>>>> most LED lamps have a build in constant current driver so they will be
>>>> the same brightness at any voltage high enough for the LEDs and
>>>> regulation
>>>>
>>>> or that they have a capacitive dropper that will only work on DC and
>>>> have a terrible power factor
>>> I checked. The only electronics on my LED lamps is a bridge rectifier.
>>>
>>> A capacitive dropper will not work on DC.
>>
>> obviously meant "only work on AC"
>
> Why do you want to drop the voltage? There are the correct number of LEDs
> in series needed to work at 120VAC.
>
> I verified there is a bridge rectifier in the LED lamps. I found a web site
> that disassembled a LED lamp and read the part number off the IC mounted on
> a small pcb. It turned out to be a bridge rectifier.
>
> The bridge rectifier in the LED lamps is needed to convert the AC line
> voltage to rectified DC as the LEDS cannot run with reversed polarity.
>
> There is no need for a constant current driver and none is installed.
There should at least be a small choke or resistor in series with the
> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>
>> fredag den 8. september 2023 kl. 21.29.18 UTC+2 skrev Mike Monett VE3BTI:
>>> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>>
>>>> most LED lamps have a build in constant current driver so they will be
>>>> the same brightness at any voltage high enough for the LEDs and
>>>> regulation
>>>>
>>>> or that they have a capacitive dropper that will only work on DC and
>>>> have a terrible power factor
>>> I checked. The only electronics on my LED lamps is a bridge rectifier.
>>>
>>> A capacitive dropper will not work on DC.
>>
>> obviously meant "only work on AC"
>
> Why do you want to drop the voltage? There are the correct number of LEDs
> in series needed to work at 120VAC.
>
> I verified there is a bridge rectifier in the LED lamps. I found a web site
> that disassembled a LED lamp and read the part number off the IC mounted on
> a small pcb. It turned out to be a bridge rectifier.
>
> The bridge rectifier in the LED lamps is needed to convert the AC line
> voltage to rectified DC as the LEDS cannot run with reversed polarity.
>
> There is no need for a constant current driver and none is installed.
LED chain in addition otherwise they will be fried by the first line
transient high enough to exceed their breakdown voltage.
The weakest one will die and that takes out the entire chain. Better
designed LED lights have constant current drive and multiple chains.
> Obviously, the LED lamps are sensitive to line voltage since they flicker
> with slight disturbances in the line voltage.
I have seen similar in the classic bulb configuration with a simple
rectifier, resistor and enough ~60 LEDs to take UK mains 240v. MTBF is
piss poor because the first LED to fail takes the entire thing down.
Better quality mains powered LED bulbs do have some capacitance and a
crude constant current supply. The ones I have are so good that even
with one phase down everything is at full brightness, but the problem
becomes obvious if I turn on the kettle which takes forever to boil.
> If a constant current driver was installed, there would be no flickering
> and no need for energy storage to ride out the transients.
Capacitors are often the weak link in LED bulbs as they get cooked.
--
Martin Brown
upsid...@downunder.com
Sep 9, 2023, 5:42:49 AM9/9/23
to
>Note the 1N4007 diodes are replaced by a regular bridge rectifier with
>suitable ratings. It is easier to model using 1N4007s than trying to find a
>bridge rectifier in LTspice.
The 1N4007 works more like a PIN diode, the other 1N400x diodes are
>suitable ratings. It is easier to model using 1N4007s than trying to find a
>bridge rectifier in LTspice.
normal diodes.
Fred Bloggs
Sep 9, 2023, 8:46:48 AM9/9/23
to
On Friday, September 8, 2023 at 11:25:43 AM UTC-4, John Larkin wrote:
> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
> <spa...@not.com> wrote:
>
> >I recently changed the overhead fluorescent lamps for LED replacements.
> >
> >Very soon, I noticed they were flickering a lot more the the old
> >fluorescents.
> >
> >They flicker on the slightest line disturbance, from someone turning on a
> >microwave to who knows what outside the building. It turns out the
> >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
> >the spying business, but not good in the shop.
> I doubt that the fluorescents are much slower, at visual speeds, than
> LEDs. You can verify that with a photodetector and an ocilloscope.
>
> Maybe you have cheap flourescent-replacement tubes.
Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
> <spa...@not.com> wrote:
>
> >I recently changed the overhead fluorescent lamps for LED replacements.
> >
> >Very soon, I noticed they were flickering a lot more the the old
> >fluorescents.
> >
> >They flicker on the slightest line disturbance, from someone turning on a
> >microwave to who knows what outside the building. It turns out the
> >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
> >the spying business, but not good in the shop.
> I doubt that the fluorescents are much slower, at visual speeds, than
> LEDs. You can verify that with a photodetector and an ocilloscope.
>
> Maybe you have cheap flourescent-replacement tubes.
Maybe he bought a "previously owned" bulb for a discount, as in previous owner ran them for 10 years..
Lasse Langwadt Christensen
Sep 9, 2023, 9:01:28 AM9/9/23
to
Fred Bloggs
Sep 9, 2023, 10:11:50 AM9/9/23
to
Lasse Langwadt Christensen
Sep 9, 2023, 10:21:24 AM9/9/23
to
John Larkin
Sep 9, 2023, 10:50:33 AM9/9/23
to
On Sat, 9 Sep 2023 05:46:43 -0700 (PDT), Fred Bloggs
<bloggs.fred...@gmail.com> wrote:
>On Friday, September 8, 2023 at 11:25:43?AM UTC-4, John Larkin wrote:
>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> <spa...@not.com> wrote:
>>
>> >I recently changed the overhead fluorescent lamps for LED replacements.
>> >
>> >Very soon, I noticed they were flickering a lot more the the old
>> >fluorescents.
>> >
>> >They flicker on the slightest line disturbance, from someone turning on a
>> >microwave to who knows what outside the building. It turns out the
>> >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> >the spying business, but not good in the shop.
>> I doubt that the fluorescents are much slower, at visual speeds, than
>> LEDs. You can verify that with a photodetector and an ocilloscope.
>>
>> Maybe you have cheap flourescent-replacement tubes.
>
>Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>
No, that's too expensive. Many have a current-limiting IC and no
energy storage. The current actually flows near the AC line peak.
<bloggs.fred...@gmail.com> wrote:
>On Friday, September 8, 2023 at 11:25:43?AM UTC-4, John Larkin wrote:
>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> <spa...@not.com> wrote:
>>
>> >I recently changed the overhead fluorescent lamps for LED replacements.
>> >
>> >Very soon, I noticed they were flickering a lot more the the old
>> >fluorescents.
>> >
>> >They flicker on the slightest line disturbance, from someone turning on a
>> >microwave to who knows what outside the building. It turns out the
>> >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> >the spying business, but not good in the shop.
>> I doubt that the fluorescents are much slower, at visual speeds, than
>> LEDs. You can verify that with a photodetector and an ocilloscope.
>>
>> Maybe you have cheap flourescent-replacement tubes.
>
>Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>
energy storage. The current actually flows near the AC line peak.
John Larkin
Sep 9, 2023, 10:55:02 AM9/9/23
to
On Sat, 9 Sep 2023 07:11:44 -0700 (PDT), Fred Bloggs
<bloggs.fred...@gmail.com> wrote:
>On Saturday, September 9, 2023 at 9:01:28?AM UTC-4, Lasse Langwadt Christensen wrote:
>> lřrdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
the base. There's no big cap, no inductor.
<bloggs.fred...@gmail.com> wrote:
>On Saturday, September 9, 2023 at 9:01:28?AM UTC-4, Lasse Langwadt Christensen wrote:
>> lřrdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
>> > On Friday, September 8, 2023 at 11:25:43?AM UTC-4, John Larkin wrote:
>> > > On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> > > <spa...@not.com> wrote:
>> > >
>> > > >I recently changed the overhead fluorescent lamps for LED replacements.
>> > > >
>> > > >Very soon, I noticed they were flickering a lot more the the old
>> > > >fluorescents.
>> > > >
>> > > >They flicker on the slightest line disturbance, from someone turning on a
>> > > >microwave to who knows what outside the building. It turns out the
>> > > >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> > > >the spying business, but not good in the shop.
>> > > I doubt that the fluorescents are much slower, at visual speeds, than
>> > > LEDs. You can verify that with a photodetector and an ocilloscope.
>> > >
>> > > Maybe you have cheap flourescent-replacement tubes.
>> > Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>> >
>> some are linear, enough LEDs in series to add up to most of the rectified line voltage
>
>I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
Get a clear-glass Edison type LED lamp. You can see the parts down in
>> > > On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> > > <spa...@not.com> wrote:
>> > >
>> > > >I recently changed the overhead fluorescent lamps for LED replacements.
>> > > >
>> > > >Very soon, I noticed they were flickering a lot more the the old
>> > > >fluorescents.
>> > > >
>> > > >They flicker on the slightest line disturbance, from someone turning on a
>> > > >microwave to who knows what outside the building. It turns out the
>> > > >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> > > >the spying business, but not good in the shop.
>> > > I doubt that the fluorescents are much slower, at visual speeds, than
>> > > LEDs. You can verify that with a photodetector and an ocilloscope.
>> > >
>> > > Maybe you have cheap flourescent-replacement tubes.
>> > Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>> >
>> some are linear, enough LEDs in series to add up to most of the rectified line voltage
>
>I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
the base. There's no big cap, no inductor.
John Larkin
Sep 9, 2023, 11:01:11 AM9/9/23
to
On Sat, 9 Sep 2023 07:21:18 -0700 (PDT), Lasse Langwadt Christensen
<lang...@fonz.dk> wrote:
>lørdag den 9. september 2023 kl. 16.11.50 UTC+2 skrev Fred Bloggs:
<lang...@fonz.dk> wrote:
>lørdag den 9. september 2023 kl. 16.11.50 UTC+2 skrev Fred Bloggs:
>> On Saturday, September 9, 2023 at 9:01:28?AM UTC-4, Lasse Langwadt Christensen wrote:
>> > lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
>> > lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
>> > > On Friday, September 8, 2023 at 11:25:43?AM UTC-4, John Larkin wrote:
>> > > > On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> > > > <spa...@not.com> wrote:
>> > > >
>> > > > >I recently changed the overhead fluorescent lamps for LED replacements.
>> > > > >
>> > > > >Very soon, I noticed they were flickering a lot more the the old
>> > > > >fluorescents.
>> > > > >
>> > > > >They flicker on the slightest line disturbance, from someone turning on a
>> > > > >microwave to who knows what outside the building. It turns out the
>> > > > >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> > > > >the spying business, but not good in the shop.
>> > > > I doubt that the fluorescents are much slower, at visual speeds, than
>> > > > LEDs. You can verify that with a photodetector and an ocilloscope.
>> > > >
>> > > > Maybe you have cheap flourescent-replacement tubes.
>> > > Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>> > >
>> > some are linear, enough LEDs in series to add up to most of the rectified line voltage
>> I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
>
>https://youtu.be/5HTa2jVi_rc?si=QA9pGKmg-w8iuZgb&t=243
>https://youtu.be/klaJqofCsu4?si=Qbkys3CHIaJnYFq9
Does Philips still sell LED bulbs? They had some really good ones that
>> > > > On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> > > > <spa...@not.com> wrote:
>> > > >
>> > > > >I recently changed the overhead fluorescent lamps for LED replacements.
>> > > > >
>> > > > >Very soon, I noticed they were flickering a lot more the the old
>> > > > >fluorescents.
>> > > > >
>> > > > >They flicker on the slightest line disturbance, from someone turning on a
>> > > > >microwave to who knows what outside the building. It turns out the
>> > > > >bandwidth of LEDs is much higher than gas lamps. Good to know if you're in
>> > > > >the spying business, but not good in the shop.
>> > > > I doubt that the fluorescents are much slower, at visual speeds, than
>> > > > LEDs. You can verify that with a photodetector and an ocilloscope.
>> > > >
>> > > > Maybe you have cheap flourescent-replacement tubes.
>> > > Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>> > >
>> > some are linear, enough LEDs in series to add up to most of the rectified line voltage
>> I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
>
>https://youtu.be/5HTa2jVi_rc?si=QA9pGKmg-w8iuZgb&t=243
>https://youtu.be/klaJqofCsu4?si=Qbkys3CHIaJnYFq9
aren't available any more. I'd expect they can't compete with the
Chinese stuff.
Lasse Langwadt Christensen
Sep 9, 2023, 11:17:01 AM9/9/23
to
Lasse Langwadt Christensen
Sep 9, 2023, 11:18:00 AM9/9/23
to
legg
Sep 9, 2023, 12:06:34 PM9/9/23
to
over a wide range - but still use a low-power LV rectifier /
electrolytic to drive the string(s) (~36VDC).
But they also have other types in the field . . . .
RL
Fred Bloggs
Sep 9, 2023, 6:35:01 PM9/9/23
to
Fred Bloggs
Sep 9, 2023, 6:36:44 PM9/9/23
to
whit3rd
Sep 9, 2023, 7:40:53 PM9/9/23
to
<https://www.ikea.com/us/en/p/solhetta-led-bulb-e26-450-lumen-globe-clear-10530117/>
certainly are 'enough LEDs in series' and not much else; there's no ROOM for more parts than that.
Lasse Langwadt Christensen
Sep 9, 2023, 7:58:52 PM9/9/23
to
that is a buck converter, schematic here: https://youtu.be/nMc6mjE9Y1s?si=lUg8dp9qZRffMQh6&t=738
Fred Bloggs
Sep 10, 2023, 10:44:38 AM9/10/23
to
Martin Brown
Sep 10, 2023, 10:57:40 AM9/10/23
to
60 LEDs in series across rectified UK 240v mains.
One single LED in the chain has failed. It was the first LED bulb
failure that I ever saw so I dismantled it to see why.
They are the cheapest and nastiest on the market, but at the time it was
bought they sold for premium prices with exaggerated MTBF based on the
expected failure time of a single LED. True MTBF is claimed/60.
--
Martin Brown
Lasse Langwadt Christensen
Sep 10, 2023, 11:10:59 AM9/10/23
to
Fred Bloggs
Sep 10, 2023, 11:18:33 AM9/10/23
to
On Sunday, September 10, 2023 at 10:57:40 AM UTC-4, Martin Brown wrote:
> On 09/09/2023 15:11, Fred Bloggs wrote:
> > On Saturday, September 9, 2023 at 9:01:28 AM UTC-4, Lasse Langwadt Christensen wrote:
> >> lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
> >>> On Friday, September 8, 2023 at 11:25:43 AM UTC-4, John Larkin wrote:
> >>>>
> >>>> Maybe you have cheap flourescent-replacement tubes.
> >>> Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
> >>>
> >> some are linear, enough LEDs in series to add up to most of the rectified line voltage
> >
> > I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
> You are wrong. I have a dead one sat in a drawer somewhere nearby.
> 60 LEDs in series across rectified UK 240v mains.
No one is interested in an example of degenerate ad hoc engineering that was completely abandoned, and for good reason.
> On 09/09/2023 15:11, Fred Bloggs wrote:
> > On Saturday, September 9, 2023 at 9:01:28 AM UTC-4, Lasse Langwadt Christensen wrote:
> >> lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
> >>> On Friday, September 8, 2023 at 11:25:43 AM UTC-4, John Larkin wrote:
> >>>>
> >>>> Maybe you have cheap flourescent-replacement tubes.
> >>> Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
> >>>
> >> some are linear, enough LEDs in series to add up to most of the rectified line voltage
> >
> > I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
> You are wrong. I have a dead one sat in a drawer somewhere nearby.
> 60 LEDs in series across rectified UK 240v mains.
Looks like a lot of these crummy Edison filament types are for chandelier applications, a decorative purpose, not a utility purpose where people want to actually see. When it comes to decor, many times bulbs are wasted by putting them behind valences to illuminate by reflection off the wall, or decorative lamp shades where the main job is to illuminate and display the shade.
Fred Bloggs
Sep 10, 2023, 11:21:07 AM9/10/23
to
Lasse Langwadt Christensen
Sep 10, 2023, 11:28:34 AM9/10/23
to
the filament one is (new) grade C
https://www.ikea.com/dk/da/p/solhetta-led-paere-e27-470-lumen-globe-klar-00498660/
Martin Brown
Sep 10, 2023, 11:28:53 AM9/10/23
to
On 10/09/2023 16:18, Fred Bloggs wrote:
> On Sunday, September 10, 2023 at 10:57:40 AM UTC-4, Martin Brown wrote:
>> On 09/09/2023 15:11, Fred Bloggs wrote:
>>> On Saturday, September 9, 2023 at 9:01:28 AM UTC-4, Lasse Langwadt Christensen wrote:
>>>> lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
>>>>> On Friday, September 8, 2023 at 11:25:43 AM UTC-4, John Larkin wrote:
>>>>>>
>>>>>> Maybe you have cheap flourescent-replacement tubes.
>>>>> Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>>>>>
>>>> some are linear, enough LEDs in series to add up to most of the rectified line voltage
>>>
>>> I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
>> You are wrong. I have a dead one sat in a drawer somewhere nearby.
>> 60 LEDs in series across rectified UK 240v mains.
>
> No one is interested in an example of degenerate ad hoc engineering that was completely abandoned, and for good reason.
They were made like that presumably to be as cheap and nasty as
> On Sunday, September 10, 2023 at 10:57:40 AM UTC-4, Martin Brown wrote:
>> On 09/09/2023 15:11, Fred Bloggs wrote:
>>> On Saturday, September 9, 2023 at 9:01:28 AM UTC-4, Lasse Langwadt Christensen wrote:
>>>> lørdag den 9. september 2023 kl. 14.46.48 UTC+2 skrev Fred Bloggs:
>>>>> On Friday, September 8, 2023 at 11:25:43 AM UTC-4, John Larkin wrote:
>>>>>>
>>>>>> Maybe you have cheap flourescent-replacement tubes.
>>>>> Uh-huh. LEDs don't flicker. They're all powered by regulated switching ***current*** sources operating in the 20kHz-30kHz range. LEDs are not directly powered by voltage, and the current sources are immune to voltage fluctuation.
>>>>>
>>>> some are linear, enough LEDs in series to add up to most of the rectified line voltage
>>>
>>> I'm pretty sure they've never used that method for the commodity lighting bulb market. Maybe for signs and indicator bulb types of applications where it has to be dirt cheap.
>> You are wrong. I have a dead one sat in a drawer somewhere nearby.
>> 60 LEDs in series across rectified UK 240v mains.
>
> No one is interested in an example of degenerate ad hoc engineering that was completely abandoned, and for good reason.
possible. When they worked they were fine and instant on with true rated
brightness unlike the previous generation of CFLs which came on dimly
and almost never reached the brightness that their packaging claimed.
>> One single LED in the chain has failed. It was the first LED bulb
>> failure that I ever saw so I dismantled it to see why.
>>
>> They are the cheapest and nastiest on the market, but at the time it was
>> bought they sold for premium prices with exaggerated MTBF based on the
>> expected failure time of a single LED. True MTBF is claimed/60.
--
Martin Brown
Fred Bloggs
Sep 10, 2023, 11:37:59 AM9/10/23
to
>
> --
> Martin Brown
Fred Bloggs
Sep 10, 2023, 11:40:27 AM9/10/23
to
Fred Bloggs
Sep 10, 2023, 11:49:22 AM9/10/23
to
Lasse Langwadt Christensen
Sep 10, 2023, 12:18:43 PM9/10/23
to
Don Y
Sep 10, 2023, 2:08:52 PM9/10/23
to
On 9/10/2023 7:57 AM, Martin Brown wrote:
> You are wrong. I have a dead one sat in a drawer somewhere nearby.
> 60 LEDs in series across rectified UK 240v mains.
I suspect that's designed with cost as the sole factor.
> You are wrong. I have a dead one sat in a drawer somewhere nearby.
> 60 LEDs in series across rectified UK 240v mains.
Most of my LED lights have just a few (e.g., less than 10)
emitters. Hard to imagine a whopping dropping resistor
to soak up ~100V of potential!
> One single LED in the chain has failed. It was the first LED bulb failure that
> I ever saw so I dismantled it to see why.
but likely would be a nightmare to REassemble -- and have
working!)
> They are the cheapest and nastiest on the market, but at the time it was bought
> they sold for premium prices with exaggerated MTBF based on the expected
> failure time of a single LED. True MTBF is claimed/60.
I have "commercial" (130V) incandescent flood lights in the
living room which I can't recall replacing after their initial
installation. They are much preferred to any of the other
technologies because they can be dimmed to a level that
can't be detected UNLESS your eyes have acclimated to total
darkness (i.e., a house guest awakening in the middle of the
night could navigate without having to figure out where
the nearest light switch was located -- and risk blinding himself
by the sudden onset of full light)
The CFLs, OTOH, never dimmed and would fail in relatively short
order -- regardless of their life expectancy claims! (I have
a CFL uplight in the office that seems like it will fail RSN...
yay! one less!!)
Lasse Langwadt Christensen
Sep 10, 2023, 3:06:37 PM9/10/23
to
søndag den 10. september 2023 kl. 20.08.52 UTC+2 skrev Don Y:
> On 9/10/2023 7:57 AM, Martin Brown wrote:
> > You are wrong. I have a dead one sat in a drawer somewhere nearby.
> > 60 LEDs in series across rectified UK 240v mains.
> I suspect that's designed with cost as the sole factor.
>
> Most of my LED lights have just a few (e.g., less than 10)
> emitters. Hard to imagine a whopping dropping resistor
> to soak up ~100V of potential!
what looks like just an LED can have internally multiple LEDs in series
> On 9/10/2023 7:57 AM, Martin Brown wrote:
> > You are wrong. I have a dead one sat in a drawer somewhere nearby.
> > 60 LEDs in series across rectified UK 240v mains.
> I suspect that's designed with cost as the sole factor.
>
> Most of my LED lights have just a few (e.g., less than 10)
> emitters. Hard to imagine a whopping dropping resistor
> to soak up ~100V of potential!
some have a forward voltage of upto 18V, i.e. 6 LEDs in series
Don Y
Sep 10, 2023, 3:59:19 PM9/10/23
to
On 9/10/2023 8:28 AM, Martin Brown wrote:
> They were made like that presumably to be as cheap and nasty as possible. When
> they worked they were fine and instant on with true rated brightness unlike the
> previous generation of CFLs which came on dimly and almost never reached the
> brightness that their packaging claimed.
Our LED lights are (RF) noisier than the CFLs were.
> They were made like that presumably to be as cheap and nasty as possible. When
> they worked they were fine and instant on with true rated brightness unlike the
> previous generation of CFLs which came on dimly and almost never reached the
> brightness that their packaging claimed.
Unlikely that a simple 60Hz rectifier would be throwing
out enough hash to piss off the (HiFi) radio!
We also have some (permanent) "night lights" that
have a short string of diodes behind a ballast
and a "controller chip" (allows the light to be
set to 4 intensity levels). I can't recall what
else was in there (tore it down some time ago
to see about making it's lowest setting, lower)
Fred Bloggs
Sep 10, 2023, 6:26:20 PM9/10/23
to
One aspect of this flicker effect not mentioned is the phosphor and its decay time. Obviously phosphor with longer decay time will attenuate the perception of flicker. Blurb from the LRC at RPI. I wasn't expecting a tutorial, but he still could have done a better write-up than this:
https://www.lrc.rpi.edu/resources/newsroom/pdf/2015/ACLEDFlicker_8511.pdf
none albert
Sep 11, 2023, 5:13:43 AM9/11/23
to
In article <87d7569f-932b-4430...@googlegroups.com>,
Two times as many leds cost two times as much obviously, but
the leds components are dirt cheap and vanish completely with
the price of total energy consumption.
>
>
>
Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat spinning. - the Wise from Antrim -
>derating also significantly increases efficiency, at the cost of
>needing more leds for the same light output
No it is not, as long as efficiency means lumens/watt.
>needing more leds for the same light output
Two times as many leds cost two times as much obviously, but
the leds components are dirt cheap and vanish completely with
the price of total energy consumption.
>
>
>
Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat spinning. - the Wise from Antrim -
Martin Brown
Sep 11, 2023, 6:45:11 AM9/11/23
to
On 11/09/2023 10:13, albert wrote:
> In article <87d7569f-932b-4430...@googlegroups.com>,
> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>
>> derating also significantly increases efficiency, at the cost of
>> needing more leds for the same light output
>
> No it is not, as long as efficiency means lumens/watt.
> Two times as many leds cost two times as much obviously, but
> the leds components are dirt cheap and vanish completely with
> the price of total energy consumption.
Unfortunately consumers look at the headline initial price to buy and
> In article <87d7569f-932b-4430...@googlegroups.com>,
> Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
>>
>> derating also significantly increases efficiency, at the cost of
>> needing more leds for the same light output
>
> No it is not, as long as efficiency means lumens/watt.
> Two times as many leds cost two times as much obviously, but
> the leds components are dirt cheap and vanish completely with
> the price of total energy consumption.
ignore the running costs. That means that the cheapest and nastiest ones
sell in the greatest quantities even if they are less reliable.
--
Martin Brown
Lasse Langwadt Christensen
Sep 11, 2023, 7:14:46 AM9/11/23
to
aka. Dubai lamp
Don Y
Sep 11, 2023, 7:49:11 AM9/11/23
to
lighting (often completely covering the cost). So, you are left with
THEIR notion of "what's best"...
Phil Hobbs
Sep 11, 2023, 12:33:45 PM9/11/23
to
On 2023-09-09 05:42, upsid...@downunder.com wrote:
> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
> <spa...@not.com> wrote:
>
>>
>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with
> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
> <spa...@not.com> wrote:
>
>>
>> suitable ratings. It is easier to model using 1N4007s than trying to find a
>> bridge rectifier in LTspice.
>
> The 1N4007 works more like a PIN diode, the other 1N400x diodes are
> normal diodes.
>
IIRC it's 1N4005 and up that are PIN structures.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com
piglet
Sep 11, 2023, 12:46:04 PM9/11/23
to
On 08/09/2023 8:10 pm, Mike Monett VE3BTI wrote:
> piglet <erichp...@hotmail.com> wrote:
>
>>
>> The model you used for 1N4007 has something very wrong - if I replace
>> with one of the 600V types included with LTSpice then the crazy currents
>> disappear and the circuit does more as you describe. Have you checked
>> Pdiss in R4?
>>
>> piglet
>
> VII doesn't have the 1N4007, so I got the model from LTspice IV. It shows a
> PIV of 1,500 v. There are no 600 V versions in IV.
>
> I see no crazy currents in IV or VII. Can you tell me more about what you are
> seeing?
>
> I tried to plot the power in R4 but had no luck in IV or VII. I tried to
> calculate pwr(V(x), V(a)) but got 9.65e+307 with no units. So I have to
> guess. I'll try a 2W wirewound.
>
>
>
Problem solved! During line wrap demangling I had corrupted the 1N4007
model Ibv=10u to become bv=10u so the extraordinary diode currents in my
sim were it breaking down at microvolts. Now it sims more like you saw.
piglet
> piglet <erichp...@hotmail.com> wrote:
>
>>
>> The model you used for 1N4007 has something very wrong - if I replace
>> with one of the 600V types included with LTSpice then the crazy currents
>> disappear and the circuit does more as you describe. Have you checked
>> Pdiss in R4?
>>
>> piglet
>
> VII doesn't have the 1N4007, so I got the model from LTspice IV. It shows a
> PIV of 1,500 v. There are no 600 V versions in IV.
>
> I see no crazy currents in IV or VII. Can you tell me more about what you are
> seeing?
>
> I tried to plot the power in R4 but had no luck in IV or VII. I tried to
> calculate pwr(V(x), V(a)) but got 9.65e+307 with no units. So I have to
> guess. I'll try a 2W wirewound.
>
>
>
Problem solved! During line wrap demangling I had corrupted the 1N4007
model Ibv=10u to become bv=10u so the extraordinary diode currents in my
sim were it breaking down at microvolts. Now it sims more like you saw.
piglet
John Larkin
Sep 11, 2023, 2:09:08 PM9/11/23
to
On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs
<pcdhSpamM...@electrooptical.net> wrote:
>On 2023-09-09 05:42, upsid...@downunder.com wrote:
>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> <spa...@not.com> wrote:
>>
>>>
>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with
>>> suitable ratings. It is easier to model using 1N4007s than trying to find a
>>> bridge rectifier in LTspice.
>>
>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are
>> normal diodes.
>>
>IIRC it's 1N4005 and up that are PIN structures.
>
>Cheers
>
>Phil Hobbs
The higher voltage rectifiers often make great drift-step-recovery
<pcdhSpamM...@electrooptical.net> wrote:
>On 2023-09-09 05:42, upsid...@downunder.com wrote:
>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>> <spa...@not.com> wrote:
>>
>>>
>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with
>>> suitable ratings. It is easier to model using 1N4007s than trying to find a
>>> bridge rectifier in LTspice.
>>
>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are
>> normal diodes.
>>
>IIRC it's 1N4005 and up that are PIN structures.
>
>Cheers
>
>Phil Hobbs
(Grehkov) diodes.
2KV negative pulse:
https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1
Phil Hobbs
Sep 11, 2023, 2:14:47 PM9/11/23
to
John Larkin
Sep 11, 2023, 5:17:31 PM9/11/23
to
On Mon, 11 Sep 2023 14:14:38 -0400, Phil Hobbs
into the DSRD.
Hers's a water-cooled Pockels Cell driver.
https://www.dropbox.com/scl/fi/5arhyamrp0bl3tgb2fasn/DSC02771.JPG?rlkey=3ttcc2yt6s9nrtdouuv3aneol&raw=1
The big problem was inductors. I kept frying them when I was making
1200 volt pulses at 4 MHz. Skin effect and such.
What worked was that air-core inductor, hand-wound on a selected
Sharpie, with a gap-pad to conduct heat through the board to the
water-cooled baseplate below.
<pcdhSpamM...@electrooptical.net> wrote:
>On 2023-09-11 14:08, John Larkin wrote:
>> On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs
>> <pcdhSpamM...@electrooptical.net> wrote:
>>
>>> On 2023-09-09 05:42, upsid...@downunder.com wrote:
>>>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>>>> <spa...@not.com> wrote:
>>>>
>>>>>
>>>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with
>>>>> suitable ratings. It is easier to model using 1N4007s than trying to find a
>>>>> bridge rectifier in LTspice.
>>>>
>>>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are
>>>> normal diodes.
>>>>
>>> IIRC it's 1N4005 and up that are PIN structures.
>>>
>>> Cheers
>>>
>>> Phil Hobbs
>>
>> The higher voltage rectifiers often make great drift-step-recovery
>> (Grehkov) diodes.
>>
>> 2KV negative pulse:
>>
>> https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1
>>
>
>I'm impressed that it survived enough pulses for a full trace. ;)
>
>Cheers
>
>Phil Hobbs
The rep-rate was low, with about 50 amps forward and reverse current
>On 2023-09-11 14:08, John Larkin wrote:
>> On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs
>> <pcdhSpamM...@electrooptical.net> wrote:
>>
>>> On 2023-09-09 05:42, upsid...@downunder.com wrote:
>>>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI
>>>> <spa...@not.com> wrote:
>>>>
>>>>>
>>>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with
>>>>> suitable ratings. It is easier to model using 1N4007s than trying to find a
>>>>> bridge rectifier in LTspice.
>>>>
>>>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are
>>>> normal diodes.
>>>>
>>> IIRC it's 1N4005 and up that are PIN structures.
>>>
>>> Cheers
>>>
>>> Phil Hobbs
>>
>> The higher voltage rectifiers often make great drift-step-recovery
>> (Grehkov) diodes.
>>
>> 2KV negative pulse:
>>
>> https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1
>>
>
>I'm impressed that it survived enough pulses for a full trace. ;)
>
>Cheers
>
>Phil Hobbs
into the DSRD.
Hers's a water-cooled Pockels Cell driver.
https://www.dropbox.com/scl/fi/5arhyamrp0bl3tgb2fasn/DSC02771.JPG?rlkey=3ttcc2yt6s9nrtdouuv3aneol&raw=1
The big problem was inductors. I kept frying them when I was making
1200 volt pulses at 4 MHz. Skin effect and such.
What worked was that air-core inductor, hand-wound on a selected
Sharpie, with a gap-pad to conduct heat through the board to the
water-cooled baseplate below.
Mike Monett VE3BTI
Sep 12, 2023, 12:46:24 AM9/12/23
to
piglet <erichp...@hotmail.com> wrote:
>
> Problem solved! During line wrap demangling I had corrupted the 1N4007
> model Ibv=10u to become bv=10u so the extraordinary diode currents in my
> sim were it breaking down at microvolts. Now it sims more like you saw.
>
> piglet
I once tried to bypass the line wrap by zipping the files and uploading to
>
> Problem solved! During line wrap demangling I had corrupted the 1N4007
> model Ibv=10u to become bv=10u so the extraordinary diode currents in my
> sim were it breaking down at microvolts. Now it sims more like you saw.
>
> piglet
Google Drive. But I got so many complaints that people could not unzip them
that I gave up.
Now, after having good experience with bare unzipped files, I may try
again.
As a favor, try this and see how it works:
https://tinyurl.com/r6r2m9kc
It will say "No Preview Available", but give you the opportunity to
download the file. Do so, and separate the files into ASC and PLT.
Now, any wrap will happen in your text editor. Set the line width to the
maximum and you should have no trouble.
I'm going to experiment with uploading ASC and PLT files directly. If I can
get Google Drive to stop using one of its editors and wrapping the lines,
then it should work.
--
MRM
Mike Monett VE3BTI
Sep 12, 2023, 1:25:50 AM9/12/23
to
> I'm going to experiment with uploading ASC and PLT files directly. If I
> can get Google Drive to stop using one of its editors and wrapping the
> lines, then it should work.
It works!
> can get Google Drive to stop using one of its editors and wrapping the
> lines, then it should work.
I gave it gibberish extentions that it doesn't know what to do with. Just
move the last letter in the extension to the first place.
ASC = CAS
PLT = TPL
Here's the files:
https://tinyurl.com/mr32zynw
- cas
https://tinyurl.com/upr8yeap
- tpl
No unzipping, no editing, no line wrap, just rename and go.
--
MRM
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