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On Wednesday, February 16, 2022 at 2:05:50 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 20:19:47 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Tuesday, February 15, 2022 at 2:01:20 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 06:04:34 -0000, Clare Snyder <cl...@snyder.on.ca> wrote:
On Mon, 14 Feb 2022 15:13:04 -0800, dpl...@coop.radagast.org (Dave
Platt) wrote:
In article <op.1hjp1...@ryzen.lan>,
Commander Kinsey <C...@nospam.com> wrote:
https://imgur.com/a/b8l5qKQ
Look at the circuit diagram. The positive of the battery is only connected through a capacitor.
How can a capacitor possibly pass DC current to allow the battery to charge?
I don\'t believe that it could.
My guess is that schematic misinterprets the nature of the yellow
disc. I suspect that it\'s not a capacitor at all, but is a
positive-temperature-coefficient thermistor - a \"soft fuse\". If the
output (to the battery) is accidentally short-circuited, the high
current flow through the PTC will cause it to heat up, increasing its
resistance, causing it to heat up even faster, causing its resistance
to increase even more... and thus limiting the current flow through
the short circuit. These PTCs usually have a \"hold current\" (which
they will allow to pass for an unlimited amount of time, at room
temperature) and a \"trip current\" which will heat them enough to cause
them to limit the current.
Since we don\'t have a profile view of this component and can\'t see
the markings, I can\'t tell for sure.
It is called \"resonant charging\" and the current is pulses - so it
DOES flow through the capacitors
see
https://www.researchgate.net/publication/327260616/figure/download/fig2/AS:664444522733570@1535427327725/Lossless-Resonant-Charging-Circuit.png
Nowhere in there does the current for the load have to pass through a capacitor.
Or it could be a TPS as described here:
A transformerless power supply (TPS) is basically just a voltage
divider that takes the 115 or 220 VAC from your wall and divides it
down to whatever voltage you want. If that voltage needs to be DC, it
is rectified through a few diodes, and maybe regulated to a maximum
voltage but weâll get to that in a minute.
Normally, DC voltage dividers are made with a pair of resistors.
Combined, they define the current flowing through the path, and the
top resistor can then be chosen to drop the difference between the
input voltage and the desired output. If, in our case, that difference
is some one or two hundred volts, even if it only has to pass a few
tens of milliamps, that resistor is going to get hot fast.
A better component to use in the top of the divider is a capacitor,
with its reactance chosen to give the desired âresistanceâ at whatever
the mains frequency is where you live. For example, say you want 25
milliamps out at 5 V, and youâre in America and need to drop 110 V. R
= V / I = 4,400 O. Using the reactance of a capacitor, thatâs C = 1 /
(2 * pi * 60 Hz * 4400) = 0.6 µF. If you need more current, use a
larger capacitor, and vice-versa. Itâs that easy!
A fully elaborated TPS design requires a few more parts. For safety,
and to limit inrush current, a fuse and a one-watt current-limiting
resistor on the input are a good idea. A large-value discharge
resistor in parallel with the reactive capacitor will keep it from
holding its high voltage and shocking you when the circuit is
unplugged.
see
https://hackaday.com/2017/04/04/the-shocking-truth-about-transformerless-power-supplies/
But nowadays they\'re electronic. Switched mode has been around for years.
So have nuclear reactors. Both are more expensive than what the Chinese suppliers pay for these cheap and dangerous power supplies. Switched power converters are significantly more expensive. Even a properly designed transformerless supply is more expensive which is why the dangerous units are sold.
Don\'t forget to check my spelling.
I prefer cheap to safe.
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
On Wed, 16 Feb 2022 15:28:11 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Wednesday, February 16, 2022 at 2:05:50 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 20:19:47 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Tuesday, February 15, 2022 at 2:01:20 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 06:04:34 -0000, Clare Snyder <cl...@snyder.on.ca> wrote:
On Mon, 14 Feb 2022 15:13:04 -0800, dpl...@coop.radagast.org (Dave
Platt) wrote:
In article <op.1hjp1...@ryzen.lan>,
Commander Kinsey <C...@nospam.com> wrote:
https://imgur.com/a/b8l5qKQ
Look at the circuit diagram. The positive of the battery is only connected through a capacitor.
How can a capacitor possibly pass DC current to allow the battery to charge?
I don\'t believe that it could.
My guess is that schematic misinterprets the nature of the yellow
disc. I suspect that it\'s not a capacitor at all, but is a
positive-temperature-coefficient thermistor - a \"soft fuse\". If the
output (to the battery) is accidentally short-circuited, the high
current flow through the PTC will cause it to heat up, increasing its
resistance, causing it to heat up even faster, causing its resistance
to increase even more... and thus limiting the current flow through
the short circuit. These PTCs usually have a \"hold current\" (which
they will allow to pass for an unlimited amount of time, at room
temperature) and a \"trip current\" which will heat them enough to cause
them to limit the current.
Since we don\'t have a profile view of this component and can\'t see
the markings, I can\'t tell for sure.
It is called \"resonant charging\" and the current is pulses - so it
DOES flow through the capacitors
see
https://www.researchgate.net/publication/327260616/figure/download/fig2/AS:664444522733570@1535427327725/Lossless-Resonant-Charging-Circuit.png
Nowhere in there does the current for the load have to pass through a capacitor.
Or it could be a TPS as described here:
A transformerless power supply (TPS) is basically just a voltage
divider that takes the 115 or 220 VAC from your wall and divides it
down to whatever voltage you want. If that voltage needs to be DC, it
is rectified through a few diodes, and maybe regulated to a maximum
voltage but weâll get to that in a minute.
Normally, DC voltage dividers are made with a pair of resistors.
Combined, they define the current flowing through the path, and the
top resistor can then be chosen to drop the difference between the
input voltage and the desired output. If, in our case, that difference
is some one or two hundred volts, even if it only has to pass a few
tens of milliamps, that resistor is going to get hot fast.
A better component to use in the top of the divider is a capacitor,
with its reactance chosen to give the desired âresistanceâ at whatever
the mains frequency is where you live. For example, say you want 25
milliamps out at 5 V, and youâre in America and need to drop 110 V. R
= V / I = 4,400 O. Using the reactance of a capacitor, thatâs C = 1 /
(2 * pi * 60 Hz * 4400) = 0.6 µF. If you need more current, use a
larger capacitor, and vice-versa. Itâs that easy!
A fully elaborated TPS design requires a few more parts. For safety,
and to limit inrush current, a fuse and a one-watt current-limiting
resistor on the input are a good idea. A large-value discharge
resistor in parallel with the reactive capacitor will keep it from
holding its high voltage and shocking you when the circuit is
unplugged.
see
https://hackaday.com/2017/04/04/the-shocking-truth-about-transformerless-power-supplies/
But nowadays they\'re electronic. Switched mode has been around for years.
So have nuclear reactors. Both are more expensive than what the Chinese suppliers pay for these cheap and dangerous power supplies. Switched power converters are significantly more expensive. Even a properly designed transformerless supply is more expensive which is why the dangerous units are sold.
Don\'t forget to check my spelling.
I prefer cheap to safe.
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
On Mon, 14 Feb 2022 07:22:30 -0500, Paul, another mentally deficient,
troll-feeding, senile asshole, blathered:
The shape of the edge of the device,
hints that it is not a disc capacitor.
The presentation of his posts, as well as his entire posting history, hints
that he is a fucking stupid troll and attention whore, troll-feeding senile
asshole!
gnuarm.del...@gmail.com wrote:
TOTAL ASSHOLE & FUCKWIT
========================
He asked a reasonable, on-topic for S.E.D. question.
** No he didn\'t.
Next he posted a pile of hostile & absurd bullshit.
Just like YOU do.
It may be a PTC thermistor current limiter.
** No fooling.......................
No one here ever ever though of that - did they ?
Yeah, I don\'t know why anyone would think it was acceptable to post \"hostile bullshit\" in s.e.d.
** So WHY do * YOU * ALL THE TIME ?????
Rhetorical Q - fuckhead
Phil, that one sailed right over your head, Whosh!
On Sun, 13 Feb 2022 15:57:26 -0800, jlarkin@highlandsniptechnology.com,
another mentally deficient, troll-feeding, senile asshole, blathered again:
It can\'t. Maybe that yellow disk is not a capacitor.
Maybe that PROVEN clinically insane attention whore is just a trolling piece
of shit, senile twit? <VBG
On Wednesday, February 16, 2022 at 11:53:34 PM UTC-5, Commander Kinsey wrote:
On Wed, 16 Feb 2022 15:28:11 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Wednesday, February 16, 2022 at 2:05:50 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 20:19:47 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Tuesday, February 15, 2022 at 2:01:20 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 06:04:34 -0000, Clare Snyder <cl...@snyder.on.ca> wrote:
On Mon, 14 Feb 2022 15:13:04 -0800, dpl...@coop.radagast.org (Dave
Platt) wrote:
In article <op.1hjp1...@ryzen.lan>,
Commander Kinsey <C...@nospam.com> wrote:
https://imgur.com/a/b8l5qKQ
Look at the circuit diagram. The positive of the battery is only connected through a capacitor.
How can a capacitor possibly pass DC current to allow the battery to charge?
I don\'t believe that it could.
My guess is that schematic misinterprets the nature of the yellow
disc. I suspect that it\'s not a capacitor at all, but is a
positive-temperature-coefficient thermistor - a \"soft fuse\". If the
output (to the battery) is accidentally short-circuited, the high
current flow through the PTC will cause it to heat up, increasing its
resistance, causing it to heat up even faster, causing its resistance
to increase even more... and thus limiting the current flow through
the short circuit. These PTCs usually have a \"hold current\" (which
they will allow to pass for an unlimited amount of time, at room
temperature) and a \"trip current\" which will heat them enough to cause
them to limit the current.
Since we don\'t have a profile view of this component and can\'t see
the markings, I can\'t tell for sure.
It is called \"resonant charging\" and the current is pulses - so it
DOES flow through the capacitors
see
https://www.researchgate.net/publication/327260616/figure/download/fig2/AS:664444522733570@1535427327725/Lossless-Resonant-Charging-Circuit.png
Nowhere in there does the current for the load have to pass through a capacitor.
Or it could be a TPS as described here:
A transformerless power supply (TPS) is basically just a voltage
divider that takes the 115 or 220 VAC from your wall and divides it
down to whatever voltage you want. If that voltage needs to be DC, it
is rectified through a few diodes, and maybe regulated to a maximum
voltage but weâll get to that in a minute.
Normally, DC voltage dividers are made with a pair of resistors.
Combined, they define the current flowing through the path, and the
top resistor can then be chosen to drop the difference between the
input voltage and the desired output. If, in our case, that difference
is some one or two hundred volts, even if it only has to pass a few
tens of milliamps, that resistor is going to get hot fast.
A better component to use in the top of the divider is a capacitor,
with its reactance chosen to give the desired âresistanceâ at whatever
the mains frequency is where you live. For example, say you want 25
milliamps out at 5 V, and youâre in America and need to drop 110 V. R
= V / I = 4,400 O. Using the reactance of a capacitor, thatâs C = 1 /
(2 * pi * 60 Hz * 4400) = 0.6 µF. If you need more current, use a
larger capacitor, and vice-versa. Itâs that easy!
A fully elaborated TPS design requires a few more parts. For safety,
and to limit inrush current, a fuse and a one-watt current-limiting
resistor on the input are a good idea. A large-value discharge
resistor in parallel with the reactive capacitor will keep it from
holding its high voltage and shocking you when the circuit is
unplugged.
see
https://hackaday.com/2017/04/04/the-shocking-truth-about-transformerless-power-supplies/
But nowadays they\'re electronic. Switched mode has been around for years.
So have nuclear reactors. Both are more expensive than what the Chinese suppliers pay for these cheap and dangerous power supplies. Switched power converters are significantly more expensive. Even a properly designed transformerless supply is more expensive which is why the dangerous units are sold.
Don\'t forget to check my spelling.
I prefer cheap to safe.
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
The light bulb has to be a switched device. Transformerless units waste a fair amount of power. Lightbulbs need to be efficient as they consume a fair amount of power and they also need to regulate the current.
A typical wall wart isn\'t and doesn\'t regulate anything very well. The junk that are sold on the Internet are literally death traps. Watch one of Big Clive\'s tear-downs on various products. He finds dangerous stuff all the time.
https://www.youtube.com/c/Bigclive/videos
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
The light bulb has to be a switched device. Transformerless units
waste a fair amount of power. Lightbulbs need to be efficient as they
consume a fair amount of power and they also need to regulate the
current.
On Sun, 13 Feb 2022 20:11:04 -0800, jlarkin@highlandsniptechnology.com,
another mentally deficient, troll-feeding senile twit, babbled again:
You could
Think hard about it
LOL Troll-feeding senile asshole still hasn\'t checked what\'s going on!
On Sun, 13 Feb 2022 15:59:33 -0800, jlarkin@highlandsniptechnology.com,
another mentally deficient, troll-feeding, senile asshole, blathered:
Try an ohmmeter.
Try not to play that clinically insane troll\'s game, senile twit! <tsk
Maybe that PROVEN clinically insane attention whore is just a trolling piece
of shit, senile twit? <VBG
I suspect he knows more about electronics than you do.
On Mon, 14 Feb 2022 07:47:20 -0800, jlarkin@highlandsniptechnology.com,
another mentally deficient, troll-feeding, senile asshole, blathered again:
Maybe that PROVEN clinically insane attention whore is just a trolling piece
of shit, senile twit? <VBG
I suspect he knows more about electronics than you do.
You poor troll-feeding senile idiot STILL didn\'t get it! <BG
On 2022-02-17, Rick C <gnuarm.del...@gmail.com> wrote:
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
The light bulb has to be a switched device. Transformerless units
waste a fair amount of power. Lightbulbs need to be efficient as they
consume a fair amount of power and they also need to regulate the
current.
They consume a few watts, tens at most. not a lot of power.
a capacitive dropper is inherently current limited.
On Thu, 17 Feb 2022 06:24:16 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Wednesday, February 16, 2022 at 11:53:34 PM UTC-5, Commander Kinsey wrote:
On Wed, 16 Feb 2022 15:28:11 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Wednesday, February 16, 2022 at 2:05:50 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 20:19:47 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Tuesday, February 15, 2022 at 2:01:20 AM UTC-5, Commander Kinsey wrote:
On Tue, 15 Feb 2022 06:04:34 -0000, Clare Snyder <cl...@snyder.on.ca> wrote:
On Mon, 14 Feb 2022 15:13:04 -0800, dpl...@coop.radagast.org (Dave
Platt) wrote:
In article <op.1hjp1...@ryzen.lan>,
Commander Kinsey <C...@nospam.com> wrote:
https://imgur.com/a/b8l5qKQ
Look at the circuit diagram. The positive of the battery is only connected through a capacitor.
How can a capacitor possibly pass DC current to allow the battery to charge?
I don\'t believe that it could.
My guess is that schematic misinterprets the nature of the yellow
disc. I suspect that it\'s not a capacitor at all, but is a
positive-temperature-coefficient thermistor - a \"soft fuse\". If the
output (to the battery) is accidentally short-circuited, the high
current flow through the PTC will cause it to heat up, increasing its
resistance, causing it to heat up even faster, causing its resistance
to increase even more... and thus limiting the current flow through
the short circuit. These PTCs usually have a \"hold current\" (which
they will allow to pass for an unlimited amount of time, at room
temperature) and a \"trip current\" which will heat them enough to cause
them to limit the current.
Since we don\'t have a profile view of this component and can\'t see
the markings, I can\'t tell for sure.
It is called \"resonant charging\" and the current is pulses - so it
DOES flow through the capacitors
see
https://www.researchgate.net/publication/327260616/figure/download/fig2/AS:664444522733570@1535427327725/Lossless-Resonant-Charging-Circuit.png
Nowhere in there does the current for the load have to pass through a capacitor.
Or it could be a TPS as described here:
A transformerless power supply (TPS) is basically just a voltage
divider that takes the 115 or 220 VAC from your wall and divides it
down to whatever voltage you want. If that voltage needs to be DC, it
is rectified through a few diodes, and maybe regulated to a maximum
voltage but weâll get to that in a minute.
Normally, DC voltage dividers are made with a pair of resistors.
Combined, they define the current flowing through the path, and the
top resistor can then be chosen to drop the difference between the
input voltage and the desired output. If, in our case, that difference
is some one or two hundred volts, even if it only has to pass a few
tens of milliamps, that resistor is going to get hot fast.
A better component to use in the top of the divider is a capacitor,
with its reactance chosen to give the desired âresistanceâ at whatever
the mains frequency is where you live. For example, say you want 25
milliamps out at 5 V, and youâre in America and need to drop 110 V. R
= V / I = 4,400 O. Using the reactance of a capacitor, thatâs C = 1 /
(2 * pi * 60 Hz * 4400) = 0.6 µF. If you need more current, use a
larger capacitor, and vice-versa. Itâs that easy!
A fully elaborated TPS design requires a few more parts. For safety,
and to limit inrush current, a fuse and a one-watt current-limiting
resistor on the input are a good idea. A large-value discharge
resistor in parallel with the reactive capacitor will keep it from
holding its high voltage and shocking you when the circuit is
unplugged.
see
https://hackaday.com/2017/04/04/the-shocking-truth-about-transformerless-power-supplies/
But nowadays they\'re electronic. Switched mode has been around for years.
So have nuclear reactors. Both are more expensive than what the Chinese suppliers pay for these cheap and dangerous power supplies. Switched power converters are significantly more expensive. Even a properly designed transformerless supply is more expensive which is why the dangerous units are sold.
Don\'t forget to check my spelling.
I prefer cheap to safe.
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
The light bulb has to be a switched device. Transformerless units waste a fair amount of power. Lightbulbs need to be efficient as they consume a fair amount of power and they also need to regulate the current.
Actually I have an old one which is just a capacitor dropper. The capacitor recently exploded so I opened it up and replaced it with a larger one.
The lightbulbs are sold through retail establishments that expect a level of quality and safety.
I\'m not stupid enough to buy anything through an expensive retail establishment.
A typical wall wart isn\'t and doesn\'t regulate anything very well. The junk that are sold on the Internet are literally death traps. Watch one of Big Clive\'s tear-downs on various products. He finds dangerous stuff all the time.
https://www.youtube.com/c/Bigclive/videos
I\'ve watched a lot of his stuff, but I\'ve never had a problem with a cheapo Chinese USB supply like this: https://www.ebay.co.uk/itm/303876456847
Mind you I\'m not scared of electricity.
On Mon, 14 Feb 2022 04:30:57 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Sunday, February 13, 2022 at 10:04:23 PM UTC-5, Commander Kinsey wrote:
On Mon, 14 Feb 2022 01:24:36 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Sunday, February 13, 2022 at 7:47:42 PM UTC-5, Commander Kinsey wrote:
On Mon, 14 Feb 2022 00:10:47 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Sunday, February 13, 2022 at 6:08:03 PM UTC-5, Commander Kinsey wrote:
On Sun, 13 Feb 2022 23:02:03 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Sunday, February 13, 2022 at 5:34:04 PM UTC-5, Commander Kinsey wrote:
On Sun, 13 Feb 2022 20:55:51 -0000, Rick C <gnuarm.del...@gmail.com> wrote:
On Sunday, February 13, 2022 at 3:33:49 PM UTC-5, Commander Kinsey wrote:
https://imgur.com/a/b8l5qKQ
Look at the circuit diagram. The positive of the battery is only connected through a capacitor. How can a capacitor possibly pass DC current to allow the battery to charge?
Maybe it\'s an AC battery? They are very useful for grid storage applications as long as you can control the phase.
What makes you think that component is a capacitor? I\'m assuming you drew the schematic.
I\'ve learned from someone on Quora that it\'s actually a PTC Fuse - a resettable semiconductor fuse.
The second image in the link shows a brown disk, which I thought was a ceramic capacitor. Looks like it\'s to stop a busted battery from being overcharged when a cell has died.
It won\'t do that. It is simply a fuse that prevents too high a current from flowing, such as if you connected the battery backwards.
Surely a higher current would flow if the battery became 9 cells instead of 10 because one failed and became zero volts? Ever tried charging a car battery with 14V when it only contains 5 working cells? The others boil.
I\'m not sure what this circuit is supposed to do. It doesn\'t look right to me.
It\'s the (5 hour) charger for a very cheap cordless drill. The input is a 14.4V wall wart. The output is to a pack of NiCad cells. It\'s worked fine for years, until I can no longer find replacement NiCad cells, so I\'m converting the battery packs to LiIon.
My point is this circuit isn\'t setting the voltage or limiting current other than through the fuse.
It will be limited by the wall wart, which is a basic transformer and diodes. Since it\'s a 5 hour charge, it won\'t harm the battery to just keep going.
It appears to be a couple of LEDs that indicate the battery is charging and/or has power.
Yes, the battery is basically just charged through the diode and fuse.
The diode will prevent the transistor from ever turning on more than a tiny amount, but with the gain of the transistor the red LED is turned on with a small current in the transistor BE path. It could be more clear if you redraw it with the base on the right, the resistor to the right of that and the diode across the two. The two resistors and the green LED probably should be on the left, where power comes in. That\'s all they do is indicate the presence of power.
Yeah it was just a quick sketch to try to understand it.
In any event, it is the wall wart that would seem to be doing all the work of charging the battery, setting the max current and the max voltage just by having a significant series resistance most likely.
Ah, you beat me to it.
That\'s why the fuse is not needed for a shorted cell. Being at 11V instead of 14V isn\'t enough to make the current jump so much. A short or reversed battery is a different matter.
Unless NiCads are vastly different to car batteries, one shorted cell makes a hell of a lot more current flow.
THE WALL WART LIMITS THE CURRENT AND PREVENTS ANY ISSUES FROM A SINGLE SHORTED CELL.
Is that clear?
Yes, so why have the semiconductor fuse at all?
[other groups reinstated to stop you limiting the audience - others may be reading this in another group]
Oh, you use google groups. My god man get a newsreader program.
As I said, when you reverse connect the battery, you double the voltage in the circuit. Rather than having a difference of a couple of volts in the EMF opposing the current, you now have a voltage that is perhaps 10 times that total. Yeah, that\'s going to push some unreasonable current though the power pack, so the fuse is needed.
Since the battery pack, like any cordless drill, has a semicircle shaped connector, it cannot possibly be connected backwards.
gnuarm.del...@gmail.com wrote:
TOTAL ASSHOLE & FUCKWIT
========================
He asked a reasonable, on-topic for S.E.D. question.
** No he didn\'t.
Next he posted a pile of hostile & absurd bullshit.
Just like YOU do.
It may be a PTC thermistor current limiter.
** No fooling.......................
No one here ever ever though of that - did they ?
Yeah, I don\'t know why anyone would think it was acceptable to post \"hostile bullshit\" in s.e.d.
** So WHY do * YOU * ALL THE TIME ?????
Rhetorical Q - fuckhead
gnuarm.del...@gmail.com :
= fucking MORON
===========================
As I said, when you reverse connect the battery, you double the voltage in the circuit.
Rather than having a difference of a couple of volts in the EMF opposing the current,
you now have a voltage that is perhaps 10 times that total.
** What do you think the fucking 1A DIODE in series does ??
Whistle Dixie ???
On Thursday, February 17, 2022 at 7:01:03 AM UTC-5, Jasen Betts wrote:
On 2022-02-17, Rick C <gnuarm.del...@gmail.com> wrote:
Yes, exactly. That\'s why it was disingenuous to post about the switched supplies. Saying, \"nowadays they\'re electronic\" would appear to be saying the transformerless supplies are not in use which is not correct.
Never looked inside one in great detail. I assumed they were switched mode, since a £4 LED bulb from China is. Never tried looking inside a tiny one, like a plug in USB PSU.
The light bulb has to be a switched device. Transformerless units
waste a fair amount of power. Lightbulbs need to be efficient as they
consume a fair amount of power and they also need to regulate the
current.
They consume a few watts, tens at most. not a lot of power.
a capacitive dropper is inherently current limited.
\"A few watts\" in most light bulbs is a lot more than a cell phone charger puts out. The purpose of LED light bulbs is to save power. Giving up 20% or more to the dissipative elements in a dropper makes the bulb significantly less efficient. No one buys cell phone chargers by their efficiency.
Being current limited is of no utility in this case. When that cheap capacitor in the cheap power supply fails, the output becomes high voltage frying devices and people. It only takes a few mA to stop the heart.
LOL Troll-feeding senile asshole still hasn\'t checked what\'s going on!
Do you know anything about electronics?
Try not to play that clinically insane troll\'s game, senile twit! <tsk
Do you own an ohmmeter?
You poor troll-feeding senile idiot STILL didn\'t get it! <BG
Confirmed.