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AC offline to low-V supply, with a cap
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Winfield Hill
Mar 6, 2019, 4:21:00 PM3/6/19
to
Years ago we had threads about the ugly but
seemingly simple scheme to get 12V DC at 5mA,
etc, with a film capacitor straight to the AC
line. We said, gotta have a series resistor
to minimize the startup inrush current.
Does anybody recall a specific instance of
this scheme being used commercially?
Paul and I are days away from turning in the
manuscript on our new x-Chapters book, and I
decided to add this and a few other cheap
AC-to-DC-power circuits, for entertainment.
So I created one with SPICE, 12V at 5mA, only
a few parts, cost under $1.50, and the series
resistor sized to limit the worst-case inrush
(cap with -170V, new line connection at +170V)
to 720 mA, with a 470-ohm 2-watt wirewound.
OK, the numbers look bad. Yes the cap current
is 90-deg out of phase with the voltage, but
not so for the 470-ohm resistor, swallowing
up power. The efficiency is less than 5%. Yes
I could reduce the 470, but its maximum pulsed
instantaneous power (0.2ms) is already 245 W.
Maybe an NTC inrush limiter, but I don't know
if the time scales are right.
--
Thanks,
- Win
seemingly simple scheme to get 12V DC at 5mA,
etc, with a film capacitor straight to the AC
line. We said, gotta have a series resistor
to minimize the startup inrush current.
Does anybody recall a specific instance of
this scheme being used commercially?
Paul and I are days away from turning in the
manuscript on our new x-Chapters book, and I
decided to add this and a few other cheap
AC-to-DC-power circuits, for entertainment.
So I created one with SPICE, 12V at 5mA, only
a few parts, cost under $1.50, and the series
resistor sized to limit the worst-case inrush
(cap with -170V, new line connection at +170V)
to 720 mA, with a 470-ohm 2-watt wirewound.
OK, the numbers look bad. Yes the cap current
is 90-deg out of phase with the voltage, but
not so for the 470-ohm resistor, swallowing
up power. The efficiency is less than 5%. Yes
I could reduce the 470, but its maximum pulsed
instantaneous power (0.2ms) is already 245 W.
Maybe an NTC inrush limiter, but I don't know
if the time scales are right.
--
Thanks,
- Win
John Larkin
Mar 6, 2019, 4:31:33 PM3/6/19
to
On 6 Mar 2019 13:20:46 -0800, Winfield Hill <hi...@rowland.harvard.edu>
wrote:
Half wave or bridge? The efficiency/surge situation is better for a
bridge.
--
John Larkin Highland Technology, Inc
picosecond timing precision measurement
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
wrote:
bridge.
--
John Larkin Highland Technology, Inc
picosecond timing precision measurement
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
Lasse Langwadt Christensen
Mar 6, 2019, 4:38:31 PM3/6/19
to
onsdag den 6. marts 2019 kl. 22.21.00 UTC+1 skrev Winfield Hill:
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
a capacitive dropper is used in a crap ton of cheap led lights
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
and then there's death traps like this:
https://youtu.be/QwqFkelUs_g?t=7m58s
Winfield Hill
Mar 6, 2019, 4:48:34 PM3/6/19
to
John Larkin wrote...
--
Thanks,
- Win
>
> Half wave or bridge? The efficiency/surge
> situation is better for a bridge.
The cheapest guys woulda gone for half-wave.
> Half wave or bridge? The efficiency/surge
> situation is better for a bridge.
--
Thanks,
- Win
bloggs.fred...@gmail.com
Mar 6, 2019, 4:55:14 PM3/6/19
to
This Snap Power Night Lite uses a circuit like you describe. This reviewer has a circuit diagram of it around the 7 minute mark.
https://www.youtube.com/watch?v=JqBZQ23TaZg
John Larkin
Mar 6, 2019, 4:56:34 PM3/6/19
to
On 6 Mar 2019 13:48:21 -0800, Winfield Hill <hi...@rowland.harvard.edu>
wrote:
>John Larkin wrote...
>>
>> Half wave or bridge? The efficiency/surge
>> situation is better for a bridge.
>
> The cheapest guys woulda gone for half-wave.
I think it is done for antiparallel strings of LEDs too.
Those fake Edison lamps. I wonder how they work.
wrote:
>John Larkin wrote...
>>
>> Half wave or bridge? The efficiency/surge
>> situation is better for a bridge.
>
> The cheapest guys woulda gone for half-wave.
Those fake Edison lamps. I wonder how they work.
Winfield Hill
Mar 6, 2019, 4:57:47 PM3/6/19
to
Lasse Langwadt Christensen wrote...
Gawwk!
No inrush resistor, and no lots of other stuff.
--
Thanks,
- Win
No inrush resistor, and no lots of other stuff.
--
Thanks,
- Win
tabb...@gmail.com
Mar 6, 2019, 5:00:34 PM3/6/19
to
170v 470R is 0.36A, why do you need to limit it to this low value? Too much R there.
0.36A x 170v = 61 watts peak in the R, not 245.
If you draw 5mA at 12v, your 470R is dropping 23.5v at 5mA, giving around 33% efficiency. Not good due to too much R, but nowhere near 5%.
The problem with NTCs:
a) you can reapply power when hot, so you can't use reduced R. Having higher R at other times is no plus
b) they tend to deteriorate.
c) they cost more
RC supplies are widespread inside appliances.
The chinese make supplies like this with touchable outputs too. They're not legal here but do turn up.
There are some basic problems with these types of supply.
a) shock obviously, or when used internally the need for more care over insulation since the LV is live.
b) Cs on mains like to fail. Look up 'wattless dropper' for plenty of stories from the valve TV days. Class X2 caps are better but some still fail. Rs taking startup pulses on mains, even when run well below their rated 200v, also have a history of failure, albeit better than that of caps.
c) Zeners are needed if you can't guarantee enough load current at all times, leading in some apps to power waste.
d) RC PSUs are only really practical for very low currents.
NT
jrwal...@gmail.com
Mar 6, 2019, 5:01:37 PM3/6/19
to
I have seen a capacitive dropper used in an electricity meter from
a reputable manufacturer.
John
a reputable manufacturer.
John
whit3rd
Mar 6, 2019, 5:26:08 PM3/6/19
to
On Wednesday, March 6, 2019 at 1:56:34 PM UTC-8, John Larkin wrote:
> Those fake Edison lamps. I wonder how they work.
Series antiparallel diodes, lots of 'em. No limiter in
> Those fake Edison lamps. I wonder how they work.
sight. The sheath around the long skinny PC boards
is the phosphor.
Winfield Hill
Mar 6, 2019, 5:41:43 PM3/6/19
to
bloggs.fred...@gmail.com wrote...
discharge resistor cuts max V in half.
--
Thanks,
- Win
> This Snap Power Night Lite uses a circuit like you describe. This
> reviewer has a circuit diagram of it around the 7 minute mark.
>
> https://www.youtube.com/watch?v=JqBZQ23TaZg
OK, full bridge reduces cap size and current,
> reviewer has a circuit diagram of it around the 7 minute mark.
>
> https://www.youtube.com/watch?v=JqBZQ23TaZg
discharge resistor cuts max V in half.
--
Thanks,
- Win
John Miles, KE5FX
Mar 6, 2019, 7:05:58 PM3/6/19
to
On Wednesday, March 6, 2019 at 2:00:34 PM UTC-8, tabb...@gmail.com wrote:
> b) Cs on mains like to fail.
No kidding. Fast edges are going to blow straight through the series C,
> b) Cs on mains like to fail.
won't they? Nearby lightning strikes, or someone plugging a nasty load
into the same power strip, or who knows what. Worst-case inrush voltage
on a power line is a lot higher than the 170V nominal peak.
IMHO this doesn't belong in AoE except as a "Bad circuit," accompanied by
an explanation of the various things that might go wrong with it.
-- john, KE5FX
John Larkin
Mar 6, 2019, 7:14:45 PM3/6/19
to
On Wed, 6 Mar 2019 14:26:04 -0800 (PST), whit3rd <whi...@gmail.com>
wrote:
Voltage straight into the LEDs? Wow.
I was just looking at one, and it does seem to have a little
electronics in the base.
wrote:
I was just looking at one, and it does seem to have a little
electronics in the base.
Lasse Langwadt Christensen
Mar 6, 2019, 7:28:58 PM3/6/19
to
Don Kuenz
Mar 6, 2019, 11:36:25 PM3/6/19
to
circuit inside of one looks like this:
+----/\/\/\------||------+-------------------+
| 56Ω 0.56µF | |
| 1W 250V _|_ `-+-,
| \ / 1N4003 /_\ 1N4749A
L o --+-- |
N o | _|_
| --+-- \ / 1N4749A
| /_\ 1N4003 `-+-,
| | |
| | |
+------------------------+-------------------+
FWIW, Todd Harrison produced a video [2] that shows how to convert a
readily available medical grade isolation transformer into a tech iso
transformer. In the video Harrison also reviews safety considerations
apropos to dropper supplies.
Notes:
1. https://www.homedepot.com/p/Defiant-180-Degree-White-Motion-Sensing-Outdoor-Security-Light-DF-5416-WH-A/203716654
2. https://youtu.be/11Yve2ijWyk
Thank you, 73,
--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.
upsid...@downunder.com
Mar 7, 2019, 1:43:17 AM3/7/19
to
On 6 Mar 2019 13:20:46 -0800, Winfield Hill <hi...@rowland.harvard.edu>
wrote:
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
Use a capacitive voltage divider, i.e. add a capacitor also across the
load. This will bypass part of the mains spikes.
> Does anybody recall a specific instance of
> this scheme being used commercially?
A few decades ago, when 4000 series CMOS and LCDs became available,
digital clocks with capacitive mains power was used.
wrote:
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
load. This will bypass part of the mains spikes.
> Does anybody recall a specific instance of
> this scheme being used commercially?
digital clocks with capacitive mains power was used.
Tauno Voipio
Mar 7, 2019, 4:27:56 AM3/7/19
to
its high-pass nature. The more transients and crud is on
the mains line, the better they get in.
--
-TV
tabb...@gmail.com
Mar 7, 2019, 5:41:46 AM3/7/19
to
On Thursday, 7 March 2019 00:05:58 UTC, John Miles, KE5FX wrote:
NT
> On Wednesday, March 6, 2019 at 2:00:34 PM UTC-8, tabby wrote:
> > b) Cs on mains like to fail.
>
> No kidding. Fast edges are going to blow straight through the series C,
> won't they? Nearby lightning strikes, or someone plugging a nasty load
> into the same power strip, or who knows what. Worst-case inrush voltage
> on a power line is a lot higher than the 170V nominal peak.
>
> IMHO this doesn't belong in AoE except as a "Bad circuit," accompanied by
> an explanation of the various things that might go wrong with it.
'Ang about. The point of the R in the supply is to limit peak inrush current to something the parts can all cope with. There's nothing disreputable about that - but the circuit does get used where it shouldn't, and there lies the problem. An EE that can't use RC PSUs is missing a basic widely used skill.
> > b) Cs on mains like to fail.
>
> No kidding. Fast edges are going to blow straight through the series C,
> won't they? Nearby lightning strikes, or someone plugging a nasty load
> into the same power strip, or who knows what. Worst-case inrush voltage
> on a power line is a lot higher than the 170V nominal peak.
>
> IMHO this doesn't belong in AoE except as a "Bad circuit," accompanied by
> an explanation of the various things that might go wrong with it.
NT
tabb...@gmail.com
Mar 7, 2019, 5:44:24 AM3/7/19
to
NT
upsid...@downunder.com
Mar 7, 2019, 7:30:31 AM3/7/19
to
On Thu, 07 Mar 2019 08:43:15 +0200, upsid...@downunder.com wrote:
>On 6 Mar 2019 13:20:46 -0800, Winfield Hill <hi...@rowland.harvard.edu>
>wrote:
>
>> Years ago we had threads about the ugly but
>> seemingly simple scheme to get 12V DC at 5mA,
>> etc, with a film capacitor straight to the AC
>> line. We said, gotta have a series resistor
>> to minimize the startup inrush current.
>
>Use a capacitive voltage divider, i.e. add a capacitor also across the
>load. This will bypass part of the mains spikes.
In a capacitive voltage divider with series capacitor Cs and hence Xs
>On 6 Mar 2019 13:20:46 -0800, Winfield Hill <hi...@rowland.harvard.edu>
>wrote:
>
>> Years ago we had threads about the ugly but
>> seemingly simple scheme to get 12V DC at 5mA,
>> etc, with a film capacitor straight to the AC
>> line. We said, gotta have a series resistor
>> to minimize the startup inrush current.
>
>Use a capacitive voltage divider, i.e. add a capacitor also across the
>load. This will bypass part of the mains spikes.
reactance and parallel capacitance Cp and reactance Xp, is used to get
12 Vac, Xs must be 18 Xp for 230 Vac mains, i.e. Cs = Cp/18. With a
load resistance Rp = 12 V / 5 mA = 2400 ohm. Using Cp 1,3 uF will give
about the same reactance and hence Cs = Cp/18 = 72 nF.
Assuming that up to 1500 V mains transients may be present, the
capacitive voltage divider voltage could be 72 V. The source impedance
at the load would be about 1 kOhm, thus the current would be about 60
mA during the transient.
Compare this with a series capacitor only with 1500 V 1 kV/us (1
kV/ms) transient.
Of course, all the calculations should be done properly with
impedances and not just reactances.
tabb...@gmail.com
Mar 7, 2019, 7:46:49 AM3/7/19
to
NT
bloggs.fred...@gmail.com
Mar 7, 2019, 11:58:15 AM3/7/19
to
It is worth noting that the SnapPower night light circuit shown does have a UL rating registration.
I wonder if UL has a standard for these kinds of supplies.
https://www.tdk-electronics.tdk.com/en/373562/tech-library/articles/applications---cases/applications---cases/everything-for-capacitive-power-supplies-from-a-single-source/1380514
This looks like a comprehensive overview of applicable standards, not sure of the date:
https://www.ieee.li/pdf/essay/safety_considerations_in_power_supply_design.pdf
>
>
> --
> Thanks,
> - Win
whit3rd
Mar 7, 2019, 4:53:13 PM3/7/19
to
On Wednesday, March 6, 2019 at 4:05:58 PM UTC-8, John Miles, KE5FX wrote:
> On Wednesday, March 6, 2019 at 2:00:34 PM UTC-8, tabb...@gmail.com wrote:
> > b) Cs on mains like to fail.
>
> No kidding. Fast edges are going to blow straight through the series C,
The obvious way to deal with that would be a choke, but price prohibits.
> On Wednesday, March 6, 2019 at 2:00:34 PM UTC-8, tabb...@gmail.com wrote:
> > b) Cs on mains like to fail.
>
> No kidding. Fast edges are going to blow straight through the series C,
How bad would a half-wave rectifier based on a Zener be? Failure mechanism
of Zener diodes can be short-circuit (which powers down the load, and
pops the input fuse/fusible-resistor), and that's a relatively safe failure.
Phil Hobbs
Mar 7, 2019, 9:15:59 PM3/7/19
to
On 3/6/19 4:20 PM, Winfield Hill wrote:
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book,
Awesome. Congratulations!
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book,
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
John Larkin
Mar 8, 2019, 1:48:40 PM3/8/19
to
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
>
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book, and I
> decided to add this and a few other cheap
> AC-to-DC-power circuits, for entertainment.
Will the x-files be a book, or a PDF? How will it be distributed?
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
>
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book, and I
> decided to add this and a few other cheap
> AC-to-DC-power circuits, for entertainment.
And how gigantic will it be?
We'll need to schedule down time for people to read it.
Don Kuenz
Mar 8, 2019, 2:33:09 PM3/8/19
to
AC outdoor security lights [1] typically use a dropper. The dropper
circuit inside of one looks like this:
http://crcomp.net/electronic/securitylight/085-5411-MB.png
circuit inside of one looks like this:
George Herold
Mar 8, 2019, 8:01:17 PM3/8/19
to
Ya gotta love diodes!
George H.
Phil Allison
Mar 8, 2019, 8:54:26 PM3/8/19
to
Don Kuenz wrote:
>
>
> AC outdoor security lights [1] typically use a dropper. The dropper
> circuit inside of one looks like this:
>
> http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
** Don't think so - no way that concoction could work or be safe.
>
>
> AC outdoor security lights [1] typically use a dropper. The dropper
> circuit inside of one looks like this:
>
> http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
> FWIW, Todd Harrison produced a video [2] that shows how to convert a
> readily available medical grade isolation transformer into a tech iso
> transformer.
Using an isolation tranny on the service bench all the time creates a false sense of security that could result in a fatal electric shock.
> In the video Harrison also reviews safety considerations
> apropos to dropper supplies.
>
Never connect them to the AC supply plug earth pin unless you intend to kill someone.
Ham radio guys should keep away from subjects they do not understand, which dos not leave much.
.... Phil
George Herold
Mar 8, 2019, 9:01:20 PM3/8/19
to
On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
> Don Kuenz wrote:
>
> >
> >
> > AC outdoor security lights [1] typically use a dropper. The dropper
> > circuit inside of one looks like this:
> >
> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> >
>
>
> ** Don't think so - no way that concoction could work or be safe.
It's a diode bridge with 24V zeners in half of the legs.
> Don Kuenz wrote:
>
> >
> >
> > AC outdoor security lights [1] typically use a dropper. The dropper
> > circuit inside of one looks like this:
> >
> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> >
>
>
> ** Don't think so - no way that concoction could work or be safe.
The first cap needs to be robust.. I'd guess.
George H.
Steve Wilson
Mar 8, 2019, 9:11:01 PM3/8/19
to
George Herold <ghe...@teachspin.com> wrote:
> On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >
>>
>>
>> ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
>
> George H.
Without an isolation transformer, ZD1 and ZD2 would be shorted by the
> On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >
>>
>>
>> ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
>
> George H.
connection between the incoming line neutral and the external connection to
ground.
George Herold
Mar 8, 2019, 9:14:54 PM3/8/19
to
(who has never done such a thing.. except for AC indicator lights.)
George H.
Phil Allison
Mar 8, 2019, 9:30:58 PM3/8/19
to
George Herold wrote:
>
> > >
> > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > >
> >
> >
> > ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
** Learn to read a circuit some time - pal.
>
> > >
> > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > >
> >
> >
> > ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
.... Phil
Don Kuenz
Mar 8, 2019, 9:52:21 PM3/8/19
to
George Herold <ghe...@teachspin.com> wrote:
> On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >
>>
>>
>> ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
Indeed. The dropper cap is rated at +250V. You obviously see how the
> On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >
>>
>>
>> ** Don't think so - no way that concoction could work or be safe.
> It's a diode bridge with 24V zeners in half of the legs.
>
> The first cap needs to be robust.. I'd guess.
zener diodes do double duty. A very interesting circuit, to those able
see it.
Steve Wilson
Mar 8, 2019, 9:54:41 PM3/8/19
to
directly to the line. If you short the output and line neutral, you will
probably blow any GFI connected to that line.
The other problem is line droppers will transmit line spikes, which can be
severe. The may disrupt sensitive electrics, such as timers, amplifiers, etc.
Best is to just get a walwart rated for the load. The transformer provides
isolation from spikes and complete freedom to connect the output wherever you
need it.
tabb...@gmail.com
Mar 8, 2019, 10:00:35 PM3/8/19
to
NT
Phil Allison
Mar 8, 2019, 10:28:54 PM3/8/19
to
Don Kuenz wrote:
>
> >> >
> >> >
> >> > AC outdoor security lights [1] typically use a dropper. The dropper
> >> > circuit inside of one looks like this:
> >> >
> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> >> >
> >>
> >>
> >> ** Don't think so - no way that concoction could work or be safe.
> > It's a diode bridge with 24V zeners in half of the legs.
> >
> > The first cap needs to be robust.. I'd guess.
>
> Indeed. The dropper cap is rated at +250V.
>
>
** The cap is not shown - why ??
>
> >> >
> >> >
> >> > AC outdoor security lights [1] typically use a dropper. The dropper
> >> > circuit inside of one looks like this:
> >> >
> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> >> >
> >>
> >>
> >> ** Don't think so - no way that concoction could work or be safe.
> > It's a diode bridge with 24V zeners in half of the legs.
> >
> > The first cap needs to be robust.. I'd guess.
>
> Indeed. The dropper cap is rated at +250V.
>
>
Active, Neutral and Earth are not shown - why ??
The dropper cap needs to be rated for AC volts, not just DC.
The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
> You obviously see how the zener diodes do double duty.
> A very iteresting circuit, to those able to see it.
** Shame you did not draw it correctly.
> Thank you, 73,
>
> --
> Don Kuenz KB7RPU
.... Phil
Don Kuenz
Mar 8, 2019, 11:41:32 PM3/8/19
to
Phil Allison <palli...@gmail.com> wrote:
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
Bear in mind that this is a reverse engineering work in progress.
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
Additional labels are now present on the schematic. The ground shown in
the bottom left side is the virtual ground. It's not the frame ground.
Here's a photo of the top side of the PCB:
http://crcomp.net/electronic/securitylight/pcbtopfront.png
The black wire and barely visible white wire are the 120VAC input. The
red wire is controlled by the blue relay at the upper middle of the PCB.
The relay's under command of a onboard microcontroller. (More about that
in a moment.) When the relay closes the red wire supplies 120VAC to a
pair of AC flood lights.
The heart of the dropper shown in my schematic appears in the upper
right hand corner of the PCB. In addition, the two large electrolytics
to the left of the relay are the smoothing capacitors for the +24VDC and
+5VDC rails. R19 and ZD3 are SMD devices on the bottom of the PCB. (More
about that in a moment.)
A PIR is under the three electrolytic capacitors beneath the relay. To
the right of the PIR is an LED and further right is the microcontroller,
which is glob top encapsulated chip and therefore almost impossible for
me to access. The glob top chip shows up better in this photo:
http://crcomp.net/electronic/securitylight/pcbtopleft.png
My goal is to add a couple of features by modifying the PCB with the
replacement of the existing glob top microcontroller with a more user
friendly microcontroller. Here's a photo of the PCB bottom:
http://crcomp.net/electronic/securitylight/pcbbottom.png
The largest copper area on the middle left is the virtual ground shown
in my schematic. ZD3 is the middle of three devices shown on the upper
edge of the largest copper area. R19 is above it.
Acrylic paint and a small artist's brush was used to highlight the
power and ground traces. Green is for ground, cadmium red is for +24VDC,
and cadmium yellow is for +5VDC.
Thank you, 73,
--
Don Kuenz KB7RPU
Don Kuenz
Mar 8, 2019, 11:43:17 PM3/8/19
to
Phil Allison <palli...@gmail.com> wrote:
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
Bear in mind that this is a reverse engineering work in progress.
Additional labels are now present on the schematic. The ground shown in
the bottom right side is the virtual ground. It's not the frame ground.
Additional labels are now present on the schematic. The ground shown in
Thank you, 73,
--
Don Kuenz KB7RPU
--
Don Kuenz KB7RPU
Don Kuenz
Mar 8, 2019, 11:49:17 PM3/8/19
to
Phil Allison <palli...@gmail.com> wrote:
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
> Don Kuenz wrote:
>> >> > AC outdoor security lights [1] typically use a dropper. The dropper
>> >> > circuit inside of one looks like this:
>> >> >
>> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>> >>
>> >> ** Don't think so - no way that concoction could work or be safe.
>> > It's a diode bridge with 24V zeners in half of the legs.
>> >
>> > The first cap needs to be robust.. I'd guess.
>>
>> Indeed. The dropper cap is rated at +250V.
>>
>
> ** The cap is not shown - why ??
>
> Active, Neutral and Earth are not shown - why ??
>
> The dropper cap needs to be rated for AC volts, not just DC.
>
> The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
>
>
>> You obviously see how the zener diodes do double duty.
>
>
> ** What does the symbol on the bottom right of the schem indicate??
>
>
> > A very iteresting circuit, to those able to see it.
>
>
> ** Shame you did not draw it correctly.
Bear in mind that this is a reverse engineering work in progress.
Additional labels are now present on the schematic. The ground shown in
the bottom right side is the virtual ground. It's not the frame ground.
Here's a photo of the top side of the PCB:
http://crcomp.net/electronic/securitylight/pcbtopfront.png
The black wire and barely visible white wire are the 120VAC input. The
red wire is controlled by the blue relay at the upper middle of the PCB.
The relay's under command of a onboard microcontroller. (More about that
in a moment.) When the relay closes the red wire supplies 120VAC to a
pair of AC flood lights.
The heart of the dropper shown in my schematic appears in the upper
right hand corner of the PCB. In addition, the two large electrolytics
to the left of the relay are the smoothing capacitors for the +24VDC and
+5VDC rails. R19 and ZD3 are SMD devices on the bottom of the PCB. (More
about that in a moment.)
A PIR is under the three electrolytic capacitors beneath the relay. To
the right of the PIR is an LED and further right is the microcontroller,
which is glob top encapsulated chip and therefore almost impossible for
me to access. The glob top chip shows up better in this photo:
http://crcomp.net/electronic/securitylight/pcbtopleft.png
My goal is to add a couple of features by modifying the PCB with the
replacement of the existing glob top microcontroller with a more user
friendly microcontroller. Here's a photo of the PCB bottom:
http://crcomp.net/electronic/securitylight/pcbbottom.png
The largest copper area on the middle right is the virtual ground shown
Additional labels are now present on the schematic. The ground shown in
the bottom right side is the virtual ground. It's not the frame ground.
Here's a photo of the top side of the PCB:
http://crcomp.net/electronic/securitylight/pcbtopfront.png
The black wire and barely visible white wire are the 120VAC input. The
red wire is controlled by the blue relay at the upper middle of the PCB.
The relay's under command of a onboard microcontroller. (More about that
in a moment.) When the relay closes the red wire supplies 120VAC to a
pair of AC flood lights.
The heart of the dropper shown in my schematic appears in the upper
right hand corner of the PCB. In addition, the two large electrolytics
to the left of the relay are the smoothing capacitors for the +24VDC and
+5VDC rails. R19 and ZD3 are SMD devices on the bottom of the PCB. (More
about that in a moment.)
A PIR is under the three electrolytic capacitors beneath the relay. To
the right of the PIR is an LED and further right is the microcontroller,
which is glob top encapsulated chip and therefore almost impossible for
me to access. The glob top chip shows up better in this photo:
http://crcomp.net/electronic/securitylight/pcbtopleft.png
My goal is to add a couple of features by modifying the PCB with the
replacement of the existing glob top microcontroller with a more user
friendly microcontroller. Here's a photo of the PCB bottom:
http://crcomp.net/electronic/securitylight/pcbbottom.png
in my schematic. ZD3 is the middle of three devices shown on the upper
edge of the largest copper area. R19 is above it.
Acrylic paint and a small artist's brush was used to highlight the
power and ground traces. Green is for ground, cadmium red is for +24VDC,
and cadmium yellow is for +5VDC.
edge of the largest copper area. R19 is above it.
Acrylic paint and a small artist's brush was used to highlight the
power and ground traces. Green is for ground, cadmium red is for +24VDC,
and cadmium yellow is for +5VDC.
Thank you, 73,
--
Don Kuenz KB7RPU
--
Don Kuenz KB7RPU
Phil Allison
Mar 9, 2019, 12:01:26 AM3/9/19
to
Don Kuenz is a Kunt wrote:
Phil Allison
> Additional labels are now present on the schematic.
** That is the SLEASIEST thing I have ever seen anyone do on usenet !!!
The bullshitting prick has posted a NEW circuit under that SAME address as the previse entirely faulty one.
What a bloody deceit !!!
Previous completely correct comments are now all rendered moot as no-one can see the old schem.
What a fucking cunt and ham radio asshole !!!
.... Phil
Phil Allison
>
> >> >> >
> >> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
> >> >>
> >> >> ** Don't think so - no way that concoction could work or be safe.
> >> > It's a diode bridge with 24V zeners in half of the legs.
> >> >
> >> > The first cap needs to be robust.. I'd guess.
> >>
> >> Indeed. The dropper cap is rated at +250V.
> >>
> >
> > ** The cap is not shown - why ??
> >
> > Active, Neutral and Earth are not shown - why ??
> >
> > The dropper cap needs to be rated for AC volts, not just DC.
> >
> > The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
> >
> >
> >> You obviously see how the zener diodes do double duty.
> >
> >
> > ** What does the symbol on the bottom right of the schem indicate??
> >
> >
> > > A very iteresting circuit, to those able to see it.
> >
> >
> > ** Shame you did not draw it correctly.
>
> Bear in mind that this is a reverse engineering work in progress.
** I bear no such damn thing in mind since you did NOT mention it before.
> >> >> >
> >> >> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
> >> >>
> >> >> ** Don't think so - no way that concoction could work or be safe.
> >> > It's a diode bridge with 24V zeners in half of the legs.
> >> >
> >> > The first cap needs to be robust.. I'd guess.
> >>
> >> Indeed. The dropper cap is rated at +250V.
> >>
> >
> > ** The cap is not shown - why ??
> >
> > Active, Neutral and Earth are not shown - why ??
> >
> > The dropper cap needs to be rated for AC volts, not just DC.
> >
> > The fact the circuit unit is "hard wired " to the supply is CRUCIAL too.
> >
> >
> >> You obviously see how the zener diodes do double duty.
> >
> >
> > ** What does the symbol on the bottom right of the schem indicate??
> >
> >
> > > A very iteresting circuit, to those able to see it.
> >
> >
> > ** Shame you did not draw it correctly.
>
> Bear in mind that this is a reverse engineering work in progress.
> Additional labels are now present on the schematic.
The bullshitting prick has posted a NEW circuit under that SAME address as the previse entirely faulty one.
What a bloody deceit !!!
Previous completely correct comments are now all rendered moot as no-one can see the old schem.
What a fucking cunt and ham radio asshole !!!
.... Phil
gnuarm.del...@gmail.com
Mar 9, 2019, 12:11:53 AM3/9/19
to
On Friday, March 8, 2019 at 9:30:58 PM UTC-5, Phil Allison wrote:
> George Herold wrote:
>
>
> >
> > > >
> > > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > > >
> > >
> > >
> > > ** Don't think so - no way that concoction could work or be safe.
> > It's a diode bridge with 24V zeners in half of the legs.
> >
> > The first cap needs to be robust.. I'd guess.
>
>
> ** Learn to read a circuit some time - pal.
That's what I like about Phil. He is always happy to give useful advice.
> George Herold wrote:
>
>
> >
> > > >
> > > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > > >
> > >
> > >
> > > ** Don't think so - no way that concoction could work or be safe.
> > It's a diode bridge with 24V zeners in half of the legs.
> >
> > The first cap needs to be robust.. I'd guess.
>
>
> ** Learn to read a circuit some time - pal.
Rick C.
gnuarm.del...@gmail.com
Mar 9, 2019, 12:15:13 AM3/9/19
to
On Saturday, March 9, 2019 at 12:01:26 AM UTC-5, Phil Allison wrote:
>
> What a fucking cunt and ham radio asshole !!!
>
>
>
>
> .... Phil
What sort of mental illness do you think Phil has? Anyone care to guess?
>
> What a fucking cunt and ham radio asshole !!!
>
>
>
>
> .... Phil
Rick C.
Phil Allison
Mar 9, 2019, 12:19:54 AM3/9/19
to
gnuarm.del...@gmail.com wrote:
> He is always happy to give useful advice.
** How would you like some - pal ??
Maybe "go fuck yourself" is good start ?
> Prick C.
** The troll and prize pricks are coming out of the cracks in the woodwork now.
.... Phil
>
> Phil Allison wrote:
> >
> > >
> > > > >
> > > > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > > > >
> > > >
> > > >
> > > > ** Don't think so - no way that concoction could work or be safe.
> > > It's a diode bridge with 24V zeners in half of the legs.
> > >
> > > The first cap needs to be robust.. I'd guess.
> >
> >
> > ** Learn to read a circuit some time - pal.
>
> That's what I like about Phil.
** Here we go ....
> Phil Allison wrote:
> >
> > >
> > > > >
> > > > > http://crcomp.net/electronic/securitylight/085-5411-MB.png
> > > > >
> > > >
> > > >
> > > > ** Don't think so - no way that concoction could work or be safe.
> > > It's a diode bridge with 24V zeners in half of the legs.
> > >
> > > The first cap needs to be robust.. I'd guess.
> >
> >
> > ** Learn to read a circuit some time - pal.
>
> That's what I like about Phil.
> He is always happy to give useful advice.
Maybe "go fuck yourself" is good start ?
> Prick C.
** The troll and prize pricks are coming out of the cracks in the woodwork now.
.... Phil
Phil Allison
Mar 9, 2019, 12:27:30 AM3/9/19
to
gnuarm.del...@gmail.com wrote:
>
>
> > What a fucking cunt and ham radio asshole !!!
> >
> >
> >
> >
> > .... Phil
>
>
>
> What sort of mental illness do you think Phil has?
>
>
** What sort of despicable, criminal convictions does this trolling Prick have?
>
>
> > What a fucking cunt and ham radio asshole !!!
> >
> >
> >
> >
> > .... Phil
>
>
>
> What sort of mental illness do you think Phil has?
>
>
Anyone car to guess ?
> Anyone care to guess?
>
> Rick C.
Nomen Nescio
Mar 9, 2019, 12:32:32 AM3/9/19
to
gnuarm.del...@gmail.com
Mar 9, 2019, 12:34:04 AM3/9/19
to
The really amazing part is that he seems to think that posting profanities on the Internet has some impact on somebody. Wow! How stupid is that???
Rick C.
Phil Allison
Mar 9, 2019, 12:47:01 AM3/9/19
to
gnuarm.del
> Phil Allison wrote:
> > > > >
> > >
> > > > What a fucking cunt and ham radio asshole !!!
> > > >
> > > >
> > > >
> > > >
> > > > .... Phil
> > >
> > >
> > >
> > > What sort of mental illness do you think Phil has?
> > >
> > >
> >
> > ** What sort of despicable, criminal convictions does this trolling Prick have?
> >
> > Anyone car to guess ?
> >
> >
> > > Anyone care to guess?
> > >
> > > Rick C.
> >
> >
> > .... Phil
>
> Yep, he is wound up now!!!
** I've only just started on lying pricks like you.
> It never takes much to set him off.
** Absurd, gross, gratuitous insults are hardly not much.
There has to be a name for what is wrong with Phil.
** There are names for what is wrong with you and you stinking ilk.
Let's start with " autistic psychopath " and gutless fuckwit troll" for examples.
> The really amazing part is that he seems to think that posting
> profanities on the Internet has some impact on somebody.
>
>
** Very strange what amazes complete morons like Prick C. The simplest things amaze folk who totally lack insight, have no honesty or any conscience whatever.
I sincerely hope a nice dose of bowel cancer is coming his.
.... Phil
> Phil Allison wrote:
> > > > >
> > >
> > > > What a fucking cunt and ham radio asshole !!!
> > > >
> > > >
> > > >
> > > >
> > > > .... Phil
> > >
> > >
> > >
> > > What sort of mental illness do you think Phil has?
> > >
> > >
> >
> > ** What sort of despicable, criminal convictions does this trolling Prick have?
> >
> > Anyone car to guess ?
> >
> >
> > > Anyone care to guess?
> > >
> > > Rick C.
> >
> >
> > .... Phil
>
> Yep, he is wound up now!!!
> It never takes much to set him off.
There has to be a name for what is wrong with Phil.
Let's start with " autistic psychopath " and gutless fuckwit troll" for examples.
> The really amazing part is that he seems to think that posting
> profanities on the Internet has some impact on somebody.
>
>
I sincerely hope a nice dose of bowel cancer is coming his.
.... Phil
upsid...@downunder.com
Mar 9, 2019, 2:53:31 AM3/9/19
to
On Fri, 8 Mar 2019 18:01:15 -0800 (PST), George Herold
<ghe...@teachspin.com> wrote:
>On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
The load seems to consume quite a lot of current (several mA)
<ghe...@teachspin.com> wrote:
>On Friday, March 8, 2019 at 8:54:26 PM UTC-5, Phil Allison wrote:
>> Don Kuenz wrote:
>>
>> >
>> >
>> > AC outdoor security lights [1] typically use a dropper. The dropper
>> > circuit inside of one looks like this:
>> >
>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
requiring quite large series capacitors. Typically capacitor input
supplies are used when only a few mA is required, so the capacitor is
smaller but still rated at sufficiently high voltage.
>> ** Don't think so - no way that concoction could work or be safe.
>It's a diode bridge with 24V zeners in half of the legs.
>
>The first cap needs to be robust.. I'd guess.
2500 V for a few seconds.
Assuming a "standard" 8/20 us lightning pulse with 2500 V peak, which
is about 300 V/us. With 0.56 uF capacitance, that makes 168 A peak
current through the capacitor i.e a practical short. Thus the 56 ohm
series resistor will take most of the transient. At 2500 V and 56
series resistor, the current would be 45 A and peak power dissipation
, of 112 kW lasting 28 uS or dissipating 3 J or actually half of that
considering pulse rise and fall times. Thus a 1 W resistor should be
sufficient, if there are several seconds between lightnings.
Unfortunately lightnings often consists of multiple hits within a few
hundred millisecond between them , so a few Watt resistor should be
used. A wire would resistor also has some inductance, limiting the
current.
In countries with non-polarized mains plug, series Y-capacitors are
used in both L and N lines.
>
>George H.
>>
>> > FWIW, Todd Harrison produced a video [2] that shows how to convert a
>> > readily available medical grade isolation transformer into a tech iso
>> > transformer.
>>
>>
>> ** Unfortunately his understanding of the safety issue is wrong.
>>
>> Using an isolation tranny on the service bench all the time creates a false sense of security that could result in a fatal electric shock.
AC/DC radios or tube televisions ;-). Just make sure that you plug in
the mains plug in the correct way so that internal metallic chassis is
directly connected to the mains neutral wire. With the plug inserted
the other way, you have direct 220 V phase voltage at the chassis.
>>
>>
>> > In the video Harrison also reviews safety considerations
>> > apropos to dropper supplies.
>> >
>>
>>
>> ** Rule 1:
>>
>> Never connect them to the AC supply plug earth pin unless you intend to kill someone.
It seems that the circuit diagram is incorrectly drawn.
Phil Allison
Mar 9, 2019, 4:34:33 AM3/9/19
to
upsid...@downunder.com wrote:
>
>
> >>
> >> ** Unfortunately his understanding of the safety issue is wrong.
> >>
> >> Using an isolation tranny on the service bench all the time creates
> >> a false sense of security that could result in a fatal electric shock.
>
>
> Who needs isolation transformers on the service bench when servicing
> AC/DC radios or tube televisions ;-). Just make sure that you plug in
> the mains plug in the correct way so that internal metallic chassis is
> directly connected to the mains neutral wire. With the plug inserted
> the other way, you have direct 220 V phase voltage at the chassis.
>
** Unfortunately, most SMPS and the like have no link from supply neutral to circuit common - only floating the AC supply and linking the AC side common to ground internally allows free use of a scope to trouble shoot the PSU.
>
>
> >>
> >> ** Unfortunately his understanding of the safety issue is wrong.
> >>
> >> Using an isolation tranny on the service bench all the time creates
> >> a false sense of security that could result in a fatal electric shock.
>
>
> Who needs isolation transformers on the service bench when servicing
> AC/DC radios or tube televisions ;-). Just make sure that you plug in
> the mains plug in the correct way so that internal metallic chassis is
> directly connected to the mains neutral wire. With the plug inserted
> the other way, you have direct 220 V phase voltage at the chassis.
>
>
> >>
> >> ** Rule 1:
> >>
> >> Never connect them to the AC supply plug earth pin unless you
> >> intend to kill someone.
>
>
> A Class II (double insulated) device never has a ground connection.
>
The vast majority of domestic audio and video equipment is Class II insulated these days - HOWEVER the metalwork and circuitry become linked to ground in normal use by being interfaced with any non Class II item. The scope on your bench is one such.
> It seems that the circuit diagram is incorrectly drawn.
>
.... Phil
upsid...@downunder.com
Mar 9, 2019, 6:54:45 AM3/9/19
to
On Sat, 9 Mar 2019 01:34:29 -0800 (PST), Phil Allison
<palli...@gmail.com> wrote:
>upsid...@downunder.com wrote:
>
>>
>>
>> >>
>> >> ** Unfortunately his understanding of the safety issue is wrong.
>> >>
>> >> Using an isolation tranny on the service bench all the time creates
>> >> a false sense of security that could result in a fatal electric shock.
>>
>>
>> Who needs isolation transformers on the service bench when servicing
>> AC/DC radios or tube televisions ;-). Just make sure that you plug in
>> the mains plug in the correct way so that internal metallic chassis is
>> directly connected to the mains neutral wire. With the plug inserted
>> the other way, you have direct 220 V phase voltage at the chassis.
>>
>
>
>** Unfortunately, most SMPS and the like have no link from supply neutral to circuit common - only floating the AC supply and linking the AC side common to ground internally allows free use of a scope to trouble shoot the PSU.
Yes, true for single phase full wave rectifier. Either use insulated,
<palli...@gmail.com> wrote:
>upsid...@downunder.com wrote:
>
>>
>>
>> >>
>> >> ** Unfortunately his understanding of the safety issue is wrong.
>> >>
>> >> Using an isolation tranny on the service bench all the time creates
>> >> a false sense of security that could result in a fatal electric shock.
>>
>>
>> Who needs isolation transformers on the service bench when servicing
>> AC/DC radios or tube televisions ;-). Just make sure that you plug in
>> the mains plug in the correct way so that internal metallic chassis is
>> directly connected to the mains neutral wire. With the plug inserted
>> the other way, you have direct 220 V phase voltage at the chassis.
>>
>
>
>** Unfortunately, most SMPS and the like have no link from supply neutral to circuit common - only floating the AC supply and linking the AC side common to ground internally allows free use of a scope to trouble shoot the PSU.
battery powered, floating test equipment, such as DVMs and battery
powered oscilloscopes.
Even better especially with higher voltage and higher power
electronics, use voltage transformers (and current transformers) to
bring the potentials down to a grounded test equipment.
>> >> ** Rule 1:
>> >>
>> >> Never connect them to the AC supply plug earth pin unless you
>> >> intend to kill someone.
>>
>>
>> A Class II (double insulated) device never has a ground connection.
>>
>
>** 100% not true.
>
>The vast majority of domestic audio and video equipment is Class II insulated these days - HOWEVER the metalwork and circuitry become linked to ground in normal use by being interfaced with any non Class II item. The scope on your bench is one such.
galvanic separation on audio, video or data connections.
Isolation of external connections is required only if the internal
circuits are forced to some dangerous (live) voltages, such as the
mains phase voltage in a AC/DC device. For a tube TV, very few
external connections were available, typically only an external
speaker connection, since there were already an audio output
transformer.
Connecting an audio tape recorder would require an expensive adaptor
(audio transformer), not to mention video connections, before
multi-MHz optoisolators become available.
Big isolated knobs were use or at least plastic potentiometer axes.
George Herold
Mar 9, 2019, 11:33:37 AM3/9/19
to
(In particular the current limiting input cap and R)
George H.
Phil Allison
Mar 9, 2019, 3:01:16 PM3/9/19
to
George Herold wrote:
>>
> > Phil Allison
> The first schematic was missing some crucial bits.
** It was as lot worse than that - but the arsehole radio ham prick ( is there another kind ? ) has VANISHED it preventing all discussion and rendering other's critical posts meaningless.
BTW:
You still need to learn how to read a circuit and plain English too.
..... Phil
>>
> > Phil Allison
>>>
>> >>
> > > >> >> ** Don't think so - no way that concoction could work or be safe.
>
> > > >
>> >>
> > > >> >> ** Don't think so - no way that concoction could work or be safe.
>
> > > >
> > > > ** The cap is not shown - why ??
> > > >
> > > > Active, Neutral and Earth are not shown - why ??
> > > >
> > > > The dropper cap needs to be rated for AC volts, not just DC.
> > > >
> > > > The fact the circuit unit is "hard wired " to the supply
> > >> is CRUCIAL too.
> > > >
> > > >
> > > >> You obviously see how the zener diodes do double duty.
> > > >
> > > >
> > > > ** What does the symbol on the bottom right of the schem indicate??
> > > >
> > > >
> > > > > A very iteresting circuit, to those able to see it.
> > > >
> > > >
> > > > ** Shame you did not draw it correctly.
> > >
> > > Bear in mind that this is a reverse engineering work in progress.
> >
> >
> > ** I bear no such damn thing in mind since you did NOT mention it before.
> >
> >
> > > Additional labels are now present on the schematic.
> >
> >
> > ** That is the SLEASIEST thing I have ever seen anyone do on usenet !!!
> >
> > The bullshitting prick has posted a NEW circuit under that SAME
> > address as the previse entirely faulty one.
> >
> > What a bloody deceit !!!
> >
> > Previous completely correct comments are now all rendered moot
> > as no-one can see the old schem.
> >
>
> It's OK Phil..
>
** So says a self serving fuckwit who failed to see all the absurd errors.
> > > >
> > > > Active, Neutral and Earth are not shown - why ??
> > > >
> > > > The dropper cap needs to be rated for AC volts, not just DC.
> > > >
> > > > The fact the circuit unit is "hard wired " to the supply
> > >> is CRUCIAL too.
> > > >
> > > >
> > > >> You obviously see how the zener diodes do double duty.
> > > >
> > > >
> > > > ** What does the symbol on the bottom right of the schem indicate??
> > > >
> > > >
> > > > > A very iteresting circuit, to those able to see it.
> > > >
> > > >
> > > > ** Shame you did not draw it correctly.
> > >
> > > Bear in mind that this is a reverse engineering work in progress.
> >
> >
> > ** I bear no such damn thing in mind since you did NOT mention it before.
> >
> >
> > > Additional labels are now present on the schematic.
> >
> >
> > ** That is the SLEASIEST thing I have ever seen anyone do on usenet !!!
> >
> > The bullshitting prick has posted a NEW circuit under that SAME
> > address as the previse entirely faulty one.
> >
> > What a bloody deceit !!!
> >
> > Previous completely correct comments are now all rendered moot
> > as no-one can see the old schem.
> >
>
> It's OK Phil..
>
> The first schematic was missing some crucial bits.
BTW:
You still need to learn how to read a circuit and plain English too.
..... Phil
Phil Allison
Mar 9, 2019, 3:27:47 PM3/9/19
to
upsid...@downunder.com wrote:
>
> >
> >** Unfortunately, most SMPS and the like have no link from supply
> > neutral to circuit common - only floating the AC supply and
> > linking the AC side common to ground internally allows free use
> > of a scope to trouble shoot the PSU.
>
>
> Yes, true for single phase full wave rectifier. Either use insulated,
> battery powered, floating test equipment, such as DVMs and battery
> powered oscilloscopes.
>
I know cos I own one, an MS15 by Non LinearSystems.
( snip crap)
>
> >> >> ** Rule 1:
> >> >>
> >> >> Never connect them to the AC supply plug earth pin unless you
> >> >> intend to kill someone.
> >>
> >>
> >> A Class II (double insulated) device never has a ground connection.
> >>
> >
> >** 100% not true.
> >
> > The vast majority of domestic audio and video equipment is
> > Class II insulated these days - HOWEVER the metalwork and circuitry
> > become linked to ground in normal use by being interfaced with
> > any non Class II item. The scope on your bench is one such.
>
>
> Class II only refers to the mains connection,
Class II is all about user safety and exposed metalwork must be "double insulated " from the AC supply and earth.
Never seen the notice: "Double Insulated - do not earth" ???
-----------------------------------------------------------
> it does not require galvanic separation on audio, video or data connections.
>
The essential requirement is that there is NO connection to supply ground by whatever means. Such connection not only eliminates the safety inherent in class 2 it also allows a horror situation in which multiple, interconnected Class II items all become electrocution hazards because of one faulty item, miswired lead or outlet.
.... Phil
upsid...@downunder.com
Mar 9, 2019, 4:50:27 PM3/9/19
to
https://en.wikipedia.org/wiki/Extra-low_voltage#Separated_or_safety_extra-low_voltage_(SELV)
Safety/Separated extra-low voltage i.e. voltages below 50 Vac or 120
Vdc, in which no external connections allowed.
I was referring to ordinary Class II LV circuits, not SELV.
Phil Allison
Mar 9, 2019, 5:25:47 PM3/9/19
to
upsid...@downunder.com wrote:
>
>Phil Allison
** No fucking way !!!
YOU are the confused one here - pal.
>
> I was referring to ordinary Class II LV circuits,
** FFS try reading up on what Class2 is all about !!!
STOP posting dangerous, complete BULLSHITTTT !!!!
What I posted is 100% FACT and you have deceitfully AVOIDED answering a single word of it so hiding you massive ignorance.
..... Phil
>
>Phil Allison
YOU are the confused one here - pal.
>
> I was referring to ordinary Class II LV circuits,
STOP posting dangerous, complete BULLSHITTTT !!!!
What I posted is 100% FACT and you have deceitfully AVOIDED answering a single word of it so hiding you massive ignorance.
..... Phil
George Herold
Mar 9, 2019, 7:30:00 PM3/9/19
to
(now updated circuit) would fail. My mistake.
George H.
>
>
> ..... Phil
gnuarm.del...@gmail.com
Mar 9, 2019, 7:56:22 PM3/9/19
to
Rick C.
tabb...@gmail.com
Mar 10, 2019, 5:38:10 AM3/10/19
to
On Saturday, 9 March 2019 20:27:47 UTC, Phil Allison wrote:
1. The essential aspect of 'double insulation' is the extra measures taken to prevent hazardous voltages appearing on external metal parts. 'Double insulation' should not be taken literally, as while some parts are required to be literally double insulated, some are not. Earthing a double insulated (or to be more precise a class 2) appliance does not negate the safety features of double insulation.
2. Earthing/grounding a class 2 metal cased device & connecting several together does not make it a shock hazard. That claim is just confused.
Time for you to rant now.
NT
> upsid...@downunder.com wrote:
> Never seen the notice: "Double Insulated - do not earth" ???
> -----------------------------------------------------------
> Never seen the notice: "Double Insulated - do not earth" ???
> -----------------------------------------------------------
> The essential requirement is that there is NO connection to supply ground by whatever means. Such connection not only eliminates the safety inherent in class 2 it also allows a horror situation in which multiple, interconnected Class II items all become electrocution hazards because of one faulty item, miswired lead or outlet.
2 errors there.
1. The essential aspect of 'double insulation' is the extra measures taken to prevent hazardous voltages appearing on external metal parts. 'Double insulation' should not be taken literally, as while some parts are required to be literally double insulated, some are not. Earthing a double insulated (or to be more precise a class 2) appliance does not negate the safety features of double insulation.
2. Earthing/grounding a class 2 metal cased device & connecting several together does not make it a shock hazard. That claim is just confused.
Time for you to rant now.
NT
gnuarm.del...@gmail.com
Mar 10, 2019, 10:27:15 AM3/10/19
to
Rick C.
Johnny B Good
Mar 10, 2019, 11:00:06 AM3/10/19
to
of walking on eggshells without cracking them?
--
Johnny B Good
John Devereux
Mar 10, 2019, 11:45:08 AM3/10/19
to
already updated when I started reading this thread today :)
--
John Devereux
Don Kuenz
Mar 10, 2019, 11:45:09 AM3/10/19
to
Winfield Hill <hi...@rowland.harvard.edu> wrote:
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
>
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book, and I
> decided to add this and a few other cheap
> AC-to-DC-power circuits, for entertainment.
> So I created one with SPICE, 12V at 5mA, only
> a few parts, cost under $1.50, and the series
> resistor sized to limit the worst-case inrush
> (cap with -170V, new line connection at +170V)
> to 720 mA, with a 470-ohm 2-watt wirewound.
>
> OK, the numbers look bad. Yes the cap current
> is 90-deg out of phase with the voltage, but
> not so for the 470-ohm resistor, swallowing
> up power. The efficiency is less than 5%. Yes
> I could reduce the 470, but its maximum pulsed
> instantaneous power (0.2ms) is already 245 W.
>
> Maybe an NTC inrush limiter, but I don't know
> if the time scales are right.
Allow me to summarize my research to make it easier for readers to
understand.
AC outdoor security lights typically use a dropper because there's
usually not a handy outdoor electrical outlet available or a wall wart.
Even when an outlet is available, wall warts are not used because
criminals will just unplug it to defeat security. The security light
shown below is UL approved and sold through outlets such as Home Depot:
https://www.homedepot.com/p/Defiant-180-Degree-White-Motion-Sensing-Outdoor-Security-Light-DF-5416-WH-A/203716654
The dropper subcircuit inside of one looks like this:
http://crcomp.net/electronic/securitylight/085-5411-MB.png
FWIW, Todd Harrison produced a video ( https://youtu.be/11Yve2ijWyk )
> Years ago we had threads about the ugly but
> seemingly simple scheme to get 12V DC at 5mA,
> etc, with a film capacitor straight to the AC
> line. We said, gotta have a series resistor
> to minimize the startup inrush current.
>
> Does anybody recall a specific instance of
> this scheme being used commercially?
>
> Paul and I are days away from turning in the
> manuscript on our new x-Chapters book, and I
> decided to add this and a few other cheap
> AC-to-DC-power circuits, for entertainment.
> So I created one with SPICE, 12V at 5mA, only
> a few parts, cost under $1.50, and the series
> resistor sized to limit the worst-case inrush
> (cap with -170V, new line connection at +170V)
> to 720 mA, with a 470-ohm 2-watt wirewound.
>
> OK, the numbers look bad. Yes the cap current
> is 90-deg out of phase with the voltage, but
> not so for the 470-ohm resistor, swallowing
> up power. The efficiency is less than 5%. Yes
> I could reduce the 470, but its maximum pulsed
> instantaneous power (0.2ms) is already 245 W.
>
> Maybe an NTC inrush limiter, but I don't know
> if the time scales are right.
Allow me to summarize my research to make it easier for readers to
understand.
AC outdoor security lights typically use a dropper because there's
usually not a handy outdoor electrical outlet available or a wall wart.
Even when an outlet is available, wall warts are not used because
criminals will just unplug it to defeat security. The security light
shown below is UL approved and sold through outlets such as Home Depot:
https://www.homedepot.com/p/Defiant-180-Degree-White-Motion-Sensing-Outdoor-Security-Light-DF-5416-WH-A/203716654
The dropper subcircuit inside of one looks like this:
http://crcomp.net/electronic/securitylight/085-5411-MB.png
that shows how to convert a readily available medical grade isolation
transformer into a tech iso transformer. In the video Harrison also
reviews safety considerations apropos to dropper supplies.
George Herold
Mar 10, 2019, 2:25:37 PM3/10/19
to
Just the bridge and following.
Phil is almost always right.
George H.
>
>
> --
>
> John Devereux
John Devereux
Mar 11, 2019, 4:02:13 PM3/11/19
to
George Herold <ghe...@teachspin.com> writes:
> On Sunday, March 10, 2019 at 11:45:08 AM UTC-4, John Devereux wrote:
[...]
> On Sunday, March 10, 2019 at 11:45:08 AM UTC-4, John Devereux wrote:
>>
>> Oh dear... yes I was wondering what Phil was on about. The circuit was
>> already updated when I started reading this thread today :)
>>
> Right, the input R's and C were missing from the first pic.
> Just the bridge and following.
>
> Phil is almost always right.
--
John Devereux
Don Kuenz
Mar 12, 2019, 4:27:28 PM3/12/19
to
upsid...@downunder.com wrote:
> On Fri, 8 Mar 2019 18:01:15 -0800 (PST), George Herold
> <ghe...@teachspin.com> wrote:
>>> Don Kuenz wrote:
>>>
>>> >
>>> >
>>> > AC outdoor security lights [1] typically use a dropper. The dropper
>>> > circuit inside of one looks like this:
>>> >
>>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
> The load seems to consume quite a lot of current (several mA)
> requiring quite large series capacitors. Typically capacitor input
> supplies are used when only a few mA is required, so the capacitor is
> smaller but still rated at sufficiently high voltage.
> On Fri, 8 Mar 2019 18:01:15 -0800 (PST), George Herold
> <ghe...@teachspin.com> wrote:
>>> Don Kuenz wrote:
>>>
>>> >
>>> >
>>> > AC outdoor security lights [1] typically use a dropper. The dropper
>>> > circuit inside of one looks like this:
>>> >
>>> > http://crcomp.net/electronic/securitylight/085-5411-MB.png
>
> The load seems to consume quite a lot of current (several mA)
> requiring quite large series capacitors. Typically capacitor input
> supplies are used when only a few mA is required, so the capacitor is
> smaller but still rated at sufficiently high voltage.
>>It's a diode bridge with 24V zeners in half of the legs.
>>
>>The first cap needs to be robust.. I'd guess.
>
> I would suggest using a standard Y-cpacitors, which are tested for
> 2500 V for a few seconds.
>
> Assuming a "standard" 8/20 us lightning pulse with 2500 V peak, which
> is about 300 V/us. With 0.56 uF capacitance, that makes 168 A peak
> current through the capacitor i.e a practical short. Thus the 56 ohm
> series resistor will take most of the transient. At 2500 V and 56
> series resistor, the current would be 45 A and peak power dissipation
> , of 112 kW lasting 28 uS or dissipating 3 J or actually half of that
> considering pulse rise and fall times. Thus a 1 W resistor should be
> sufficient, if there are several seconds between lightnings.
> Unfortunately lightnings often consists of multiple hits within a few
> hundred millisecond between them , so a few Watt resistor should be
> used. A wire would resistor also has some inductance, limiting the
> current.
>
> In countries with non-polarized mains plug, series Y-capacitors are
> used in both L and N lines.
>>>
>>
>>The first cap needs to be robust.. I'd guess.
>
> I would suggest using a standard Y-cpacitors, which are tested for
> 2500 V for a few seconds.
>
> Assuming a "standard" 8/20 us lightning pulse with 2500 V peak, which
> is about 300 V/us. With 0.56 uF capacitance, that makes 168 A peak
> current through the capacitor i.e a practical short. Thus the 56 ohm
> series resistor will take most of the transient. At 2500 V and 56
> series resistor, the current would be 45 A and peak power dissipation
> , of 112 kW lasting 28 uS or dissipating 3 J or actually half of that
> considering pulse rise and fall times. Thus a 1 W resistor should be
> sufficient, if there are several seconds between lightnings.
> Unfortunately lightnings often consists of multiple hits within a few
> hundred millisecond between them , so a few Watt resistor should be
> used. A wire would resistor also has some inductance, limiting the
> current.
>
> In countries with non-polarized mains plug, series Y-capacitors are
> used in both L and N lines.
>>>
>>> > FWIW, Todd Harrison produced a video [2] that shows how to convert a
>>> > readily available medical grade isolation transformer into a tech iso
>>> > transformer.
>>> > readily available medical grade isolation transformer into a tech iso
>>> > transformer.
> Who needs isolation transformers on the service bench when servicing
> AC/DC radios or tube televisions ;-). Just make sure that you plug in
> the mains plug in the correct way so that internal metallic chassis is
> directly connected to the mains neutral wire. With the plug inserted
> the other way, you have direct 220 V phase voltage at the chassis.
>>> > In the video Harrison also reviews safety considerations
>>> > apropos to dropper supplies.
> AC/DC radios or tube televisions ;-). Just make sure that you plug in
> the mains plug in the correct way so that internal metallic chassis is
> directly connected to the mains neutral wire. With the plug inserted
> the other way, you have direct 220 V phase voltage at the chassis.
>>> > In the video Harrison also reviews safety considerations
>>> > apropos to dropper supplies.
> A Class II (double insulated) device never has a ground connection.
>
> It seems that the circuit diagram is incorrectly drawn.
The dropper's a polyester capacitor that's identical to these capacitors:
>
> It seems that the circuit diagram is incorrectly drawn.
https://www.ebay.com/itm/0-56uF-560nF-250V-Red-Polyester-Capacitors-564-10pcs-/302218260256
Part of the load's a relay coil that draws 15mA @ 24VDC. Although
it's unknown how much the glob top, 22-pin microcontroller draws, the
venerable 20-pin PIC16F84 draws up to 100mA.
It took me a few minutes to figure out that gschem crops the
schematic to the visible area when you zoom-in and export a PNG to a
website. The PNG was re-exported to my website afterward.
Phil Allison
Mar 12, 2019, 4:53:59 PM3/12/19
to
tabb..is a fucking MORON
> 'Double insulation' should not be taken literally, as while some parts
> are required to be literally double insulated, some are not.
** Meaningless.
> Earthing a double insulated (or to be more precise a class 2) appliance
> does not negate the safety features of double insulation.
>
** It very obviously does.
> 2. Earthing/grounding a class 2 metal cased device & connecting
> several together does not make it a shock hazard.
>
** It very obviously does.
The tabb fuckwit has no clue and posts no case.
So there is " no case to answer ".
FOAD you pile of puss.
.... Phil
>
>Phil Allison wrote:
>
> > Never seen the notice: "Double Insulated - do not earth" ???
> > -----------------------------------------------------------
>
> > The essential requirement is that there is NO connection to
> > supply ground by whatever means. Such connection not only eliminates
> > the safety inherent in class 2 it also allows a horror situation
> > in which multiple, interconnected Class II items all become
> > electrocution hazards because of one faulty item, miswired lead or
> > outlet.
>
>
>
> 2 errors there.
>
> 1. The essential aspect of 'double insulation' is the extra measures
> taken to prevent hazardous voltages appearing on external metal parts.
>
** Grounding achieves the same result - so that is not true.
>Phil Allison wrote:
>
> > Never seen the notice: "Double Insulated - do not earth" ???
> > -----------------------------------------------------------
>
> > The essential requirement is that there is NO connection to
> > supply ground by whatever means. Such connection not only eliminates
> > the safety inherent in class 2 it also allows a horror situation
> > in which multiple, interconnected Class II items all become
> > electrocution hazards because of one faulty item, miswired lead or
> > outlet.
>
>
>
> 2 errors there.
>
> 1. The essential aspect of 'double insulation' is the extra measures
> taken to prevent hazardous voltages appearing on external metal parts.
>
> 'Double insulation' should not be taken literally, as while some parts
> are required to be literally double insulated, some are not.
> Earthing a double insulated (or to be more precise a class 2) appliance
> does not negate the safety features of double insulation.
>
> 2. Earthing/grounding a class 2 metal cased device & connecting
> several together does not make it a shock hazard.
>
The tabb fuckwit has no clue and posts no case.
So there is " no case to answer ".
FOAD you pile of puss.
.... Phil
gnuarm.del...@gmail.com
Mar 12, 2019, 7:54:43 PM3/12/19
to
On Tuesday, March 12, 2019 at 4:53:59 PM UTC-4, Phil Allison wrote:
> tabb..is a fucking MORON
> FOAD you pile of puss.
>
>
> .... Phil
Yes, I can tell that Phil is getting a bit softer around the edges as he matures.
Rick C.
> tabb..is a fucking MORON
> FOAD you pile of puss.
>
>
> .... Phil
Rick C.
George Herold
Mar 12, 2019, 8:12:53 PM3/12/19
to
On Tuesday, March 12, 2019 at 4:53:59 PM UTC-4, Phil Allison wrote:
(and knowing nothing of classes..
https://en.wikipedia.org/wiki/Appliance_classes
)
I read class 2 as being floating.. not once but twice.
But what do I know...?
George H.
Phil Allison
Mar 12, 2019, 8:41:22 PM3/12/19
to
George Herold wrote:
>
>
> I read class 2 as being floating.. not once but twice.
>
> But what do I know...?
>
** Not much.
>
>
> I read class 2 as being floating.. not once but twice.
>
> But what do I know...?
>
Class II construction is a formula for removing the shock hazard of an appliance by eliminating the possibility of exposed metalwork becoming live.
Additional insulation is used beyond that needed for the unit to function - plus means are included that prevent the insulation becoming damaged by hot supply current carrying conductors under overload or fault conditions.
Yes, the exposed metalwork is left "floating" and as such it can neither be the source of nor provide an earth path for an electric shock.
.... Phil
George Herold
Mar 12, 2019, 9:01:56 PM3/12/19
to
On Tuesday, March 12, 2019 at 8:41:22 PM UTC-4, Phil Allison wrote:
> George Herold wrote:
>
>
> >
> >
> > I read class 2 as being floating.. not once but twice.
> >
> > But what do I know...?
> >
>
> ** Not much.
Grin :^) about class 2.. already conceded.
> George Herold wrote:
>
>
> >
> >
> > I read class 2 as being floating.. not once but twice.
> >
> > But what do I know...?
> >
>
> ** Not much.
If you have questions about the angular momentum/ spin
states of Rubidium.. hit me up!
(magnetometers, atomic clocks, ... )
George H.
Phil Allison
Mar 12, 2019, 9:09:17 PM3/12/19
to
George Herold wrote:
>
> > George Herold wrote:
> >
> >
> >
> > > I read class 2 as being floating.. not once but twice.
> > >
> > > But what do I know...?
> > >
> >
> > ** Not much.
>
> Grin :^) about class 2.. already conceded.
>
> If you have questions about the angular momentum/ spin
> states of Rubidium.. hit me up!
> (magnetometers, atomic clocks, ... )
>
>
** How many angels can dance on the head of a pin ?
>
> > George Herold wrote:
> >
> >
> >
> > > I read class 2 as being floating.. not once but twice.
> > >
> > > But what do I know...?
> > >
> >
> > ** Not much.
>
> Grin :^) about class 2.. already conceded.
>
> If you have questions about the angular momentum/ spin
> states of Rubidium.. hit me up!
> (magnetometers, atomic clocks, ... )
>
>
.... Phil
upsid...@downunder.com
Mar 13, 2019, 1:42:42 AM3/13/19
to
On Tue, 12 Mar 2019 17:12:49 -0700 (PDT), George Herold
<ghe...@teachspin.com> wrote:
>
>Having shown myself to be the Jester on this thread,
>(and knowing nothing of classes..
>https://en.wikipedia.org/wiki/Appliance_classes
>)
>I read class 2 as being floating.. not once but twice.
>
The double insulated application class is Class II (not Class 2).
<ghe...@teachspin.com> wrote:
>
>Having shown myself to be the Jester on this thread,
>(and knowing nothing of classes..
>https://en.wikipedia.org/wiki/Appliance_classes
>)
>I read class 2 as being floating.. not once but twice.
>
Phil seems to mix Class II with Class III, which is a SELV (Separate
Extra-Low voltage) contraption, in which no other connections are
allowed.
One classical example is work lights for working _inside_ a metallic
container, which requires an ELV lamp (typically less than 24 Vac) fed
by an external isolation transformer with primary and secondary in
separate slots. The secondary side connection is two pole only and a
special type connector is used to allow only a simple lamp to be
connected to the isolation transformer. Possibly also a fixed cable
connection between isolation transformer and lamp to prevent other
connections to the ELV line.
Phil Allison
Mar 13, 2019, 2:06:23 AM3/13/19
to
upsid...compleet fucking IDIOT wrote:
>
> The double insulated application class is Class II (not Class 2).
>
> Phil seems to mix Class II with Class III,
** What utter BULLSHIT !!!!!
>
> The double insulated application class is Class II (not Class 2).
>
> Phil seems to mix Class II with Class III,
.... Phil
tabb...@gmail.com
Mar 13, 2019, 9:23:32 AM3/13/19
to
On Tuesday, 12 March 2019 20:53:59 UTC, the frothing Phil Allison wrote:
> tabbypurr
Earth/ground/CPC voltage can rise due to high fault current into a local earth electrode. In (can't remember the word, but systems able to disconnect power in that scenario) systems mandated here from 1955 (but not always implemented) that CPC shock voltage is transient. In noncompliant systems that shock voltage can remain indefinitely. This is a weakness of earthing/grounding metal appliance cases. Vulnerability to wiring errors is another issue.
Class II is immune to those issues, but able to become dangerously live as a result of connecting to another faulty appliance. It is also vulnerable to causing shock from poor manufacture with inadequate insulation, whereas class I is not vulnerable to that.
> > 'Double insulation' should not be taken literally, as while some parts
> > are required to be literally double insulated, some are not.
>
>
> ** Meaningless.
it means what it says
> > Earthing a double insulated (or to be more precise a class 2) appliance
> > does not negate the safety features of double insulation.
> >
>
> ** It very obviously does.
No, either way the user is normally safe from shock. It's only edge cases where there is any effective difference.
> > 2. Earthing/grounding a class 2 metal cased device & connecting
> > several together does not make it a shock hazard.
> >
>
> ** It very obviously does.
it very obviously does not. Phil very obviously does not understand this topic.
> The tabb fuckwit has no clue and posts no case.
>
> So there is " no case to answer ".
>
> FOAD you pile of puss.
>
>
> .... Phil
and has some other problems as we can see.
NT
> tabbypurr
> >Phil Allison wrote:
> > > Never seen the notice: "Double Insulated - do not earth" ???
> > > -----------------------------------------------------------
> >
> > > The essential requirement is that there is NO connection to
> > > supply ground by whatever means. Such connection not only eliminates
> > > the safety inherent in class 2 it also allows a horror situation
> > > in which multiple, interconnected Class II items all become
> > > electrocution hazards because of one faulty item, miswired lead or
> > > outlet.
> >
> >
> >
> > 2 errors there.
> >
> > 1. The essential aspect of 'double insulation' is the extra measures
> > taken to prevent hazardous voltages appearing on external metal parts.
> >
>
> ** Grounding achieves the same result - so that is not true.
not quite. Both shock protection schemes have different issues, both can end up causing a shock under some uncommon situations.
> > > Never seen the notice: "Double Insulated - do not earth" ???
> > > -----------------------------------------------------------
> >
> > > The essential requirement is that there is NO connection to
> > > supply ground by whatever means. Such connection not only eliminates
> > > the safety inherent in class 2 it also allows a horror situation
> > > in which multiple, interconnected Class II items all become
> > > electrocution hazards because of one faulty item, miswired lead or
> > > outlet.
> >
> >
> >
> > 2 errors there.
> >
> > 1. The essential aspect of 'double insulation' is the extra measures
> > taken to prevent hazardous voltages appearing on external metal parts.
> >
>
> ** Grounding achieves the same result - so that is not true.
Earth/ground/CPC voltage can rise due to high fault current into a local earth electrode. In (can't remember the word, but systems able to disconnect power in that scenario) systems mandated here from 1955 (but not always implemented) that CPC shock voltage is transient. In noncompliant systems that shock voltage can remain indefinitely. This is a weakness of earthing/grounding metal appliance cases. Vulnerability to wiring errors is another issue.
Class II is immune to those issues, but able to become dangerously live as a result of connecting to another faulty appliance. It is also vulnerable to causing shock from poor manufacture with inadequate insulation, whereas class I is not vulnerable to that.
> > 'Double insulation' should not be taken literally, as while some parts
> > are required to be literally double insulated, some are not.
>
>
> ** Meaningless.
> > Earthing a double insulated (or to be more precise a class 2) appliance
> > does not negate the safety features of double insulation.
> >
>
> ** It very obviously does.
> > 2. Earthing/grounding a class 2 metal cased device & connecting
> > several together does not make it a shock hazard.
> >
>
> ** It very obviously does.
> The tabb fuckwit has no clue and posts no case.
>
> So there is " no case to answer ".
>
> FOAD you pile of puss.
>
>
> .... Phil
NT
tabb...@gmail.com
Mar 13, 2019, 9:25:17 AM3/13/19
to
NT
Phil Allison
Mar 13, 2019, 3:47:20 PM3/13/19
to
tabb... is a lying Nut Case
> > >Phil Allison wrote:
>
> > > > Never seen the notice: "Double Insulated - do not earth" ???
> > > > -----------------------------------------------------------
> > >
> > > > The essential requirement is that there is NO connection to
> > > > supply ground by whatever means. Such connection not only eliminates
> > > > the safety inherent in class 2 it also allows a horror situation
> > > > in which multiple, interconnected Class II items all become
> > > > electrocution hazards because of one faulty item, miswired lead or
> > > > outlet.
> > >
> > >
> > >
> > > 2 errors there.
> > >
> > > 1. The essential aspect of 'double insulation' is the extra measures
> > > taken to prevent hazardous voltages appearing on external metal parts.
> > >
> >
> > ** Grounding achieves the same result - so that is not true.
>
> not quite.
** Meaningless.
> > > 'Double insulation' should not be taken literally, as while some parts
> > > are required to be literally double insulated, some are not.
> >
> >
> > ** Meaningless.
>
> it means what it says
** And is inherently meaningless - like you.
> > > Earthing a double insulated (or to be more precise a class 2) appliance
> > > does not negate the safety features of double insulation.
> > >
> >
> > ** It very obviously does.
>
> No,
** Shame about the prohibition: " ... do not earth".
This pig ignorant lying cunt has wanked itself blind.
> > > 2. Earthing/grounding a class 2 metal cased device & connecting
> > > several together does not make it a shock hazard.
> > >
> >
> > ** It very obviously does.
>
> it very obviously does not.
** It very obviously does and YOU have no answer.
The tab fuckwit TROLL has no clue, no case and makes no sense.
The is simply nothing for me to answer.
But like any autistic fuckwit on usenet, he will never give up.
..... Phil
> > >Phil Allison wrote:
>
> > > > Never seen the notice: "Double Insulated - do not earth" ???
> > > > -----------------------------------------------------------
> > >
> > > > The essential requirement is that there is NO connection to
> > > > supply ground by whatever means. Such connection not only eliminates
> > > > the safety inherent in class 2 it also allows a horror situation
> > > > in which multiple, interconnected Class II items all become
> > > > electrocution hazards because of one faulty item, miswired lead or
> > > > outlet.
> > >
> > >
> > >
> > > 2 errors there.
> > >
> > > 1. The essential aspect of 'double insulation' is the extra measures
> > > taken to prevent hazardous voltages appearing on external metal parts.
> > >
> >
> > ** Grounding achieves the same result - so that is not true.
>
> not quite.
> > > 'Double insulation' should not be taken literally, as while some parts
> > > are required to be literally double insulated, some are not.
> >
> >
> > ** Meaningless.
>
> it means what it says
> > > Earthing a double insulated (or to be more precise a class 2) appliance
> > > does not negate the safety features of double insulation.
> > >
> >
> > ** It very obviously does.
>
> No,
This pig ignorant lying cunt has wanked itself blind.
> > > 2. Earthing/grounding a class 2 metal cased device & connecting
> > > several together does not make it a shock hazard.
> > >
> >
> > ** It very obviously does.
>
> it very obviously does not.
The tab fuckwit TROLL has no clue, no case and makes no sense.
The is simply nothing for me to answer.
But like any autistic fuckwit on usenet, he will never give up.
..... Phil
Phil Allison
Mar 13, 2019, 3:49:07 PM3/13/19
to
tabb...is a lying ASD fucked idiot
>
> correct, at least under the usual circumstances. Occasionally
> those don't apply of course.
>
>
** FOAD you TROLLING pile of garbage.
>
> correct, at least under the usual circumstances. Occasionally
> those don't apply of course.
>
>
tabb...@gmail.com
Mar 14, 2019, 5:31:31 AM3/14/19
to
tabb...@gmail.com
Mar 14, 2019, 6:04:24 AM3/14/19
to
On Wednesday, 13 March 2019 13:23:32 UTC, tabbypurr wrote:
> On Tuesday, 12 March 2019 20:53:59 UTC, the frothing Phil Allison wrote:
> > tabbypurr
> > >Phil Allison wrote:
> > > 1. The essential aspect of 'double insulation' is the extra measures
> > > taken to prevent hazardous voltages appearing on external metal parts.
> > >
> >
> > ** Grounding achieves the same result - so that is not true.
>
> not quite. Both shock protection schemes have different issues, both can end up causing a shock under some uncommon situations.
>
> Earth/ground/CPC voltage can rise due to high fault current into a local earth electrode. In (can't remember the word, but systems able to disconnect power in that scenario) systems mandated here from 1955 (but not always
EEBAD it's called.
> On Tuesday, 12 March 2019 20:53:59 UTC, the frothing Phil Allison wrote:
> > tabbypurr
> > >Phil Allison wrote:
> > > 1. The essential aspect of 'double insulation' is the extra measures
> > > taken to prevent hazardous voltages appearing on external metal parts.
> > >
> >
> > ** Grounding achieves the same result - so that is not true.
>
> not quite. Both shock protection schemes have different issues, both can end up causing a shock under some uncommon situations.
>
> Earth/ground/CPC voltage can rise due to high fault current into a local earth electrode. In (can't remember the word, but systems able to disconnect power in that scenario) systems mandated here from 1955 (but not always
implemented) that CPC shock voltage is transient. In noncompliant systems that shock voltage can remain indefinitely. This is a weakness of earthing/grounding metal appliance cases. Vulnerability to wiring errors is another issue.
>
> Class II is immune to those issues, but able to become dangerously live as a result of connecting to another faulty appliance. It is also vulnerable to causing shock from poor manufacture with inadequate insulation, whereas class I is not vulnerable to that.
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