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Default Bit OT, compact, low current 220/110 step down transformer?

Sorta OT, sorta on topic... I have a really cool light bulb, clear
glass, inside is a metallic flower with leaves on the stem. When under
power, the petals and leaves generate a soft glowing corona. Looks
really cool.

I doubt this bulb would like being hit with 220 when I get down under. I
want to make an artistic, sorta steam-punkish base to show it off
(metalworking content), and would like to incorporate as compact a
stepdown transformer as possible. Have no idea what the current draw is.
Travel step down transformers generally caution against continuous duty,
but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


Jon
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Default Bit OT, compact, low current 220/110 step down transformer?

janders fired this volley in news:yNLnt.40352
:

Have no idea what the current draw is.
Travel step down transformers generally caution against continuous

duty,
but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


I couldn't be sure without seeing it, but that sounds like a gas-
discharge lamp (like a neon bulb, but perhaps a gas blend that gives a
different color).

If so, you need only a limiting resistor.

Bets are off if there are electronics in the base of the bulb. In that
case, I'd say it's voltage sensitive, and you'll need some way to drop
the voltage.

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Lloyd

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Default Bit OT, compact, low current 220/110 step down transformer?

janders fired this volley in news:yNLnt.40352
:

. Thoughts?
Or


I might add this: If it's a "regular" neon, it may already have a limiting
resistor in the base. If you can examine it for its value, just add
another of the same resistance at wattage in series with the lamp.

Lloyd
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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

I couldn't be sure without seeing it, but that sounds like a gas-
discharge lamp (like a neon bulb, but perhaps a gas blend that gives a
different color).

If so, you need only a limiting resistor.


Picture's worth a thousand words... G
https://picasaweb.google.com/lh/photo/HR9gnIj6F9INyHaO0T1HqtMTjNZETYmyPJy0liipFm0?feat=d irectlink

Doubt highly there's any electronics involved. So, for an electronics
idiot, would you mind explaining a bit more on current limiting
resistors for something like this? I assume it'll have to dissipate
heat. Might it get hot enough that using part of the base as a heat sink
could result in a burn? But I like the idea of something as simple as a
resistor, make it a lot easier to hide in the base.

This won't be run all the time, just for effect now and then, maybe few
hours at a time.

Or is the small power transformer a better way to go?

Regards,

Jon
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Default Bit OT, compact, low current 220/110 step down transformer?

Ah, just found them via Google, here's an images result:
https://www.google.com/search?q=gaseous+discharge+lamps&safe=off&hl=en&so urce=lnms&tbm=isch&sa=X&ei=Fa-fUZqkK8XOigLpq4CQDg&sqi=2&ved=0CAcQ_AUoAQ&biw=1275 &bih=838#safe=off&hl=en&tbm=isch&sa=1&q=light+bulb +flower+filament&oq=light+bulb+flower&gs_l=img.3.4 .0l4j0i24l2.37167.42523.0.48071.21.14.2.0.0.0.442. 3337.0j7j4j2j1.14.0...0.0...1c.1.14.img.kKRv_i-Vnj0&bav=on.2,or.r_qf.&bvm=bv.47008514,d.cGE&fp=46 e29c28ac62cb39&biw=1275&bih=838

Pretty cool, eh?


Jon


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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/24/2013 11:29 AM, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon


any transformer with a 220V input and a 110 v secondary (or 115 or 120
or anything reasonably close) will work - when you get to AU just pull
apart an old something or other and repurpose the transformer, or go to
a surplus store. Though things cost more there, surplus stores still exist
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Default Bit OT, compact, low current 220/110 step down transformer?

janders fired this volley in news:TjOnt.137887
:

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


It should not.

From the pictures you showed, your lamp has both a filament and gasseous-
discharge elements. If that's the case, you must use a transformer.

There are "multi-voltage" transformers (not "powerpacks", per se, which
are often switching power supplies).

If a transformer has the ability to operate on either 220 or 110, then it
certainly has either two 110V windings, or a center-tapped 220V winding.

As long as it's rated for more VA (watts... approximately) as the light
bulb, then using it in autoformer mode would be fine.

The drill would be to connect the two primaries in series (if it's that
type). Then connect one 'outside' lead to neutral, and the other outside
lead to 220V. Then the center tap (which you've created joining two
primaries, if that's the case) will have 110V to neutral.

Don't attempt to connect between the center tap and the 'high' lead. It
will work, but it will also make the whole apparatus 'float' at 110V
above ground... which isn't safe.

Lloyd


Lloyd
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Default Bit OT, compact, low current 220/110 step down transformer?

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon

I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.
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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 11:18:05 -0700, janders
wrote:

On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

I couldn't be sure without seeing it, but that sounds like a gas-
discharge lamp (like a neon bulb, but perhaps a gas blend that gives a
different color).

If so, you need only a limiting resistor.


Picture's worth a thousand words... G
https://picasaweb.google.com/lh/photo/HR9gnIj6F9INyHaO0T1HqtMTjNZETYmyPJy0liipFm0?feat=d irectlink

Doubt highly there's any electronics involved. So, for an electronics
idiot, would you mind explaining a bit more on current limiting
resistors for something like this? I assume it'll have to dissipate
heat. Might it get hot enough that using part of the base as a heat sink
could result in a burn? But I like the idea of something as simple as a
resistor, make it a lot easier to hide in the base.

This won't be run all the time, just for effect now and then, maybe few
hours at a time.

Or is the small power transformer a better way to go?

Regards,

Jon

I'd definitely go with a small transformer - or a simple dimmer if it
has a filament.


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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 11:29:17 -0700, janders
wrote:

On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon

Still works.
And you have a 3 watt bulb if it's like the Damar , so you don't need
a honking big transformer..

Google "115/230V DUAL PRIMARY TRANSFORMER" there is one for $12.50
plus shipping.
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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/24/2013 2:12 PM, wrote:

Google "115/230V DUAL PRIMARY TRANSFORMER" there is one for $12.50
plus shipping.


Works for me, thanks!


Jon
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Default Bit OT, compact, low current 220/110 step down transformer?

It happens that David Billington formulated :
On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in Australia,
220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon

I would expect Australia to be like the UK so you would have live, neutral
and ground, where neutral and ground are tied together at the substation, and
live is one leg of the 3 phase distribution system for a single phase supply.
So you would get 220V from live to ground or neutral, neutral to ground
should be 0V but might have a small difference but it should be very small.


You are correct about the live to ground etc but the nominal line to
neutral voltage is 240 volts as it is in the UK. and it is often
higher.

Many houses including mine have 3 phase and neutral for the aircon etc.

GROUND is wired everywhere, light fittings included, but is never
current carrying in normal operation.

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no gaurentee that is what you get.

--
John G


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Default Bit OT, compact, low current 220/110 step down transformer?


John G wrote:

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no guarantee that is what you get.



My line voltage has run 124.5/249 to 127/254 for over 12 years,
except during power outages. I haven't seen anything under 120/240
since the early '60s
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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 22:39:46 -0400, "Michael A. Terrell"
wrote:


John G wrote:

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no guarantee that is what you get.



My line voltage has run 124.5/249 to 127/254 for over 12 years,
except during power outages. I haven't seen anything under 120/240
since the early '60s


Same here in California


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Really?

"Hurt" aint the word.

For Liberals, the truth is like salt to a slug.
Sunlight to a vampire.
Raid® to a cockroach.
Sheriff Brody to a shark
Bush to a Liberal

The truth doesn't just hurt. It's painful, like a red hot poker shoved
up their ass. Like sliding down a hundred foot razor blade using their
dick as a brake.

They HATE the truth."



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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 08:36:34 -0700, janders
wrote:

Sorta OT, sorta on topic... I have a really cool light bulb, clear
glass, inside is a metallic flower with leaves on the stem. When under
power, the petals and leaves generate a soft glowing corona. Looks
really cool.

I doubt this bulb would like being hit with 220 when I get down under. I
want to make an artistic, sorta steam-punkish base to show it off
(metalworking content), and would like to incorporate as compact a
stepdown transformer as possible. Have no idea what the current draw is.
Travel step down transformers generally caution against continuous duty,
but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


Jon


All you need is a 2 - 1 transformer. I don't know about Australia but
certainly most S. Asia countries are awash with them.
--
Cheers,

John B.
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Default Bit OT, compact, low current 220/110 step down transformer?

Michael A. Terrell explained on 25/05/2013 :
John G wrote:

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no guarantee that is what you get.



My line voltage has run 124.5/249 to 127/254 for over 12 years,
except during power outages. I haven't seen anything under 120/240
since the early '60s


Yes higher and not lower is my experience here in AUS but of course 245
or 250 and I am first off a 400KVA transformer for a bigger street
loop than is common off pole pigs in the US.

--
John G


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Default Bit OT, compact, low current 220/110 step down transformer?

John B. formulated on Saturday :
On Fri, 24 May 2013 08:36:34 -0700, janders
wrote:

Sorta OT, sorta on topic... I have a really cool light bulb, clear
glass, inside is a metallic flower with leaves on the stem. When under
power, the petals and leaves generate a soft glowing corona. Looks
really cool.

I doubt this bulb would like being hit with 220 when I get down under. I
want to make an artistic, sorta steam-punkish base to show it off
(metalworking content), and would like to incorporate as compact a
stepdown transformer as possible. Have no idea what the current draw is.
Travel step down transformers generally caution against continuous duty,
but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


Jon


All you need is a 2 - 1 transformer. I don't know about Australia but
certainly most S. Asia countries are awash with them.


They are easy to buy at Jaycar etc but disposals shops don't seem to be
very common in Aus. All our manufacturing has gone to China ;-)

http://search.jaycar.com.au/search?w...%20transformer

--
John G


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Default Bit OT, compact, low current 220/110 step down transformer?

I'd think to call a couple travel agencies from the phone book. Explain your need, and ask for a travel transformer. See what they have. Then, buy one for retail, as they provided valuable advice

On the cheap, you can likely research your destination's power, and buy a step down from Ebay or Amazon.
..
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..
"janders" wrote in message ...
Sorta OT, sorta on topic... I have a really cool light bulb, clear
glass, inside is a metallic flower with leaves on the stem. When under
power, the petals and leaves generate a soft glowing corona. Looks
really cool.

I doubt this bulb would like being hit with 220 when I get down under. I
want to make an artistic, sorta steam-punkish base to show it off
(metalworking content), and would like to incorporate as compact a
stepdown transformer as possible. Have no idea what the current draw is.
Travel step down transformers generally caution against continuous duty,
but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


Jon

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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/24/2013 9:21 PM, John G wrote:

They are easy to buy at Jaycar etc but disposals shops don't seem to be
very common in Aus. All our manufacturing has gone to China ;-)


Picked up a Jaycar catalog on a previous visit, forgot about that.
There's a store in Wagga, about an hour away from my eventual home.
Suspect I'll be in there on a fairly regular basis...

Jon


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Default Bit OT, compact, low current 220/110 step down transformer?

In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.


Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon

I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.


I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn
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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 11:21:18 -0700, janders
wrote:

Ah, just found them via Google, here's an images result:
https://www.google.com/search?q=gaseous+discharge+lamps&safe=off&hl=en&so urce=lnms&tbm=isch&sa=X&ei=Fa-fUZqkK8XOigLpq4CQDg&sqi=2&ved=0CAcQ_AUoAQ&biw=1275 &bih=838#safe=off&hl=en&tbm=isch&sa=1&q=light+bulb +flower+filament&oq=light+bulb+flower&gs_l=img.3.4 .0l4j0i24l2.37167.42523.0.48071.21.14.2.0.0.0.442. 3337.0j7j4j2j1.14.0...0.0...1c.1.14.img.kKRv_i-Vnj0&bav=on.2,or.r_qf.&bvm=bv.47008514,d.cGE&fp=46 e29c28ac62cb39&biw=1275&bih=838

Pretty cool, eh?


Yeah, really. I think I'll grab a couple as a little gift for my
niece.

I was shopping eBay today and came across an interesting, and
previously unheard by me, term on one of their strings of LEDs:

Protection Rate: Un-waterproof.


Cracked me up, it did.

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those who have taken authority as truth,
rather than truth as authority.
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Default Bit OT, compact, low current 220/110 step down transformer?

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon

I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.


I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn


The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts)
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).

Of course as with most of the Hi voltage part of the world the
frequency is 50 Hz.

--
John G


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Default Bit OT, compact, low current 220/110 step down transformer?

In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.


I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn


The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).


Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.

Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?


Of course as with most of the Hi voltage part of the world the
frequency is 50 Hz.


Yes. General rule is ~100 volts is 60 Hz, while ~240 volts is 50 Hz.
Except that Japan has a 50 Hz and a 60 Hz region, if my memory is
correct. Don't know the history, but would guess that WW2 has
something to do with it.

Joe Gwinn
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Default Bit OT, compact, low current 220/110 step down transformer?

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn


The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).


Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.

Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.
Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is ccomingup to the harmonized 230
I believe.

Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?

Do not think there is any general use of Corner grounds at any level in
Aus.

There is some SWER (Single Wire Earth Return)in rural areas and I have
no idea what voltage that is but each user has a pole pig to get 240V.

Of course as with most of the Hi voltage part of the world the
frequency is 50 Hz.


Yes. General rule is ~100 volts is 60 Hz, while ~240 volts is 50 Hz.
Except that Japan has a 50 Hz and a 60 Hz region, if my memory is
correct. Don't know the history, but would guess that WW2 has
something to do with it.

Japan had some 100 volts as well.

Joe Gwinn


--
John G




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Default Bit OT, compact, low current 220/110 step down transformer?

On 5/25/2013 4:37 PM, Larry Jaques wrote:

Protection Rate: Un-waterproof.
Cracked me up, it did.


That's there's funny...


Jon
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Default Bit OT, compact, low current 220/110 step down transformer?


Stormin Mormon wrote:

I'd think to call a couple travel agencies from the phone book. Explain your need, and ask for a travel transformer. See what they have. Then, buy one for retail, as they provided valuable advice

On the cheap, you can likely research your destination's power, and buy a step down from Ebay or Amazon.



On the cheap, you'll get the equivalent of a light dimmer for purely
resistive loads or small universal motors. It will damage or destroy
any other type of load.
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Default Bit OT, compact, low current 220/110 step down transformer?


John G wrote:

Michael A. Terrell explained on 25/05/2013 :
John G wrote:

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no guarantee that is what you get.



My line voltage has run 124.5/249 to 127/254 for over 12 years,
except during power outages. I haven't seen anything under 120/240
since the early '60s


Yes higher and not lower is my experience here in AUS but of course 245
or 250 and I am first off a 400KVA transformer for a bigger street
loop than is common off pole pigs in the US.



I prefer the US system. Less people are affected when repairs are
needed. Long drops have a single home stepdown transformer and a lot
of 'Pole pigs' are really pad mounted transformers.

All that 400 KVA feed does in increase the chances of a fire from an
arc, since the interrupt current is higher. Since the typical US home
service around here is 200A @240, your 400 KVA is little more than
double, than four the four homes on one transformer that's quite common
around here, and breakers have to be rated for 10 KA interrupt current.
I/R losses are lower at 7200V than at 240 V. That improves regulation,
and lowers distribution losses.
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Default Bit OT, compact, low current 220/110 step down transformer?

On 2013-05-24, janders wrote:
Sorta OT, sorta on topic... I have a really cool light bulb, clear
glass, inside is a metallic flower with leaves on the stem. When under
power, the petals and leaves generate a soft glowing corona. Looks
really cool.


Corona? What color? If orange, it is likely Neon, which
probably strikes at about 90V, and then draws down to about 60-70V
across the terminals.

Normal operation is to put a resistor in series to limit the
current to what makes sense for the bulb itself. (The neon pilot lamps,
for 120 VAC, normally would have something like 220K in series.

At the area of the electrodes would be much larger, a lower
value resistor would be involved -- which is best determined (in the
absence of a data sheet for the bulb) by examining the circuit it is
mounted it. Find the value of the resistor, divide it into the voltage
left when running (say about 50-60 V), and then multiply that by the
voltage difference between your 50-60V and the 240, so about 180 V.
Replace the resistor with one of the value you calculated, and multiply
the calculated current by the 180 V to determine the required wattage.
No transformer needed.

However -- if it is some kind of high voltage setup, you
will probably need the transformer -- unless it has an input voltage
switch.

And if it is incandescent -- glowing hot filaments instead of
glowing surface areas, you will need a step-down transformer, and for
that you will need to determine the wattage the bulb draws.

I doubt this bulb would like being hit with 220 when I get down under. I
want to make an artistic, sorta steam-punkish base to show it off
(metalworking content), and would like to incorporate as compact a
stepdown transformer as possible. Have no idea what the current draw is.
Travel step down transformers generally caution against continuous duty,


This is assuming a significant wattage. Since the wattage of a
neon lamp is very low, pretty much anything will work for a long time.
Rather than looking for a step-down transformer, I would look for a
small power supply transformer with dual voltage primaries. Both in
parallel for 120 VAC, both in series for 240 VAC. Wire them in series,
and run the lamp off one side of the transformer (the low side, since
they ground one side of their 240 VAC) and the center tap.

but wondering if maybe a quality one might work. I'd strip internals
from the case and rearrange inside the base. Thoughts?
Or is there a simple and small step down transformer that is even more
compact? And yes, hoping the bulb lives long enough to justify the
effort...


Have you looked inside the case yet? Perhaps it already has a
transformer? Perhaps it even has the taps for 120 or 240 VAC operation?

It all depends on what kind of lamp it is. Decorative filament
lamps may be made to run from 120 VAC, or from a much lower voltage --
24 VAC, 12 VAC. or even 6 VAC. Do your homework by looking inside it
*now*, while you are where you can get more parts more easily.

Good Luck,
DoN.


--
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Email: | Voice (all times): (703) 938-4564
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Default Bit OT, compact, low current 220/110 step down transformer?

Hi Don,

The bulb itself simply screws into any standard light socket and
operates directly on 120v. There are no electronics whatever in the base
of the bulb. I posted a link to a place I found that sells them (though
I'd never seen them before buying this one used, they are not as rare as
I thought).

Thought hit me last night to do some searching on google.au, someone
might be making these to run directly on 220 down there. That would make
the whole voltage conversion moot. I was looking into that thinking I
had something rather unusual and a bit rare.

Jon


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Posts: 416
Default Bit OT, compact, low current 220/110 step down transformer?

In article , John G
wrote:

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn

The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).


Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.


Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.


So, you have four large non-green wires coming into your home?


Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is coming up to the harmonized 230
I believe.


I did find stuff about this voltage harmonization on the web.


Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?


Do not think there is any general use of Corner grounds at any level in
Aus.


OK. Perhaps I'll recall where I saw this claimed. I think it was in a
thread on RCM, some years ago. RCM folk were jealous of the Aussies
for having access to three-phase power in homes.


There is some SWER (Single Wire Earth Return)in rural areas and I have
no idea what voltage that is but each user has a pole pig to get 240V.


Sounds like what is done in rural areas of the US.

The intent of the original US efforts to develop rotating phase
converters was to generate three phase for the powering of irrigation
pumps, because three phase induction motors are simpler, cheaper, and
more reliable than single-phase, especially in irrigation-pump sizes.


Of course as with most of the Hi voltage part of the world the
frequency is 50 Hz.


Yes. General rule is ~100 volts is 60 Hz, while ~240 volts is 50 Hz.
Except that Japan has a 50 Hz and a 60 Hz region, if my memory is
correct. Don't know the history, but would guess that WW2 has
something to do with it.

Japan had some 100 volts as well.


My understanding is that Japan is all 100 volt. Their wall outlets
look like US outlets, but with thicker blades. It's only the frequency
that varied.

Joe Gwinn
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Default Bit OT, compact, low current 220/110 step down transformer?

On Sun, 26 May 2013 07:51:01 -0700, janders wrote:
The bulb itself simply screws into any standard light socket and
operates directly on 120v. There are no electronics whatever in the base
of the bulb. I posted a link to a place I found that sells them (though
I'd never seen them before buying this one used, they are not as rare as
I thought).

Thought hit me last night to do some searching on google.au, someone
might be making these to run directly on 220 down there. That would make
the whole voltage conversion moot. I was looking into that thinking I
had something rather unusual and a bit rare.


You probably could run two of the 120v decorative bulbs in series
on 240v, or if you know the wattage of the decorative bulb, run one
in series with an incandescent bulb of the same wattage. Of
course if either bulb burns out both of them turn off.

--
jiw
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Default Bit OT, compact, low current 220/110 step down transformer?

Joe Gwinn explained :
In article , John G
wrote:

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn

The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).

Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.


Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.


So, you have four large non-green wires coming into your home?

Yes

Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is coming up to the harmonized 230
I believe.


I did find stuff about this voltage harmonization on the web.


Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?


Do not think there is any general use of Corner grounds at any level in
Aus.


OK. Perhaps I'll recall where I saw this claimed. I think it was in a
thread on RCM, some years ago. RCM folk were jealous of the Aussies
for having access to three-phase power in homes.


I can understand the jealousy but I think they were wrong or ill
informed about Corner grounds. In fact all, in my relativly wide
experience, houshold distribution is 4 wire WYE 240/415 volts in Aus
With only one phase delivered unless there is a larger load.
Remember a lot of Aus has a rether mild climate with a large proportion
living below the snow line or below the Tropic of Capricorn so it is
only in more recent times that Air Cons hve become very popular and
Dryers work fine on one 2Kw service 240 volts 10 amps.

There is some SWER (Single Wire Earth Return)in rural areas and I have
no idea what voltage that is but each user has a pole pig to get 240V.


Sounds like what is done in rural areas of the US.

The intent of the original US efforts to develop rotating phase
converters was to generate three phase for the powering of irrigation
pumps, because three phase induction motors are simpler, cheaper, and
more reliable than single-phase, especially in irrigation-pump sizes.


Of course as with most of the Hi voltage part of the world the
frequency is 50 Hz.

Yes. General rule is ~100 volts is 60 Hz, while ~240 volts is 50 Hz.
Except that Japan has a 50 Hz and a 60 Hz region, if my memory is
correct. Don't know the history, but would guess that WW2 has
something to do with it.

Japan had some 100 volts as well.


My understanding is that Japan is all 100 volt. Their wall outlets
look like US outlets, but with thicker blades. It's only the frequency
that varied.

Yes

Joe Gwinn


--
John G


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Default Bit OT, compact, low current 220/110 step down transformer?

I have two Neon Masonic bulbs. They have a resistor in the base hidden
in the screw base. Typical values are in the 20,000 to 30,000 range of
ohms.

What you want to do is to double what it has. You can do this
experimentally by having a socket that you can add a series resistance
(in line of a wire) and it will be in series with the the one inside of
the bulb.

You will need a 220 volt power plug - sounds like a dryer plug is ideal.
A dryer will have three or four slots for the plug. Two are the Legs
of the AC line and one or two are neutral(possible) and ground(required).

Between the lines is 220v. might be 208... That is a source of 220.
Have a resistor in the 50k value and a 30k and 20k. Use the 20 and 30
to make 50. series resistors add. See if the brightness is what it
was on 120. - dim - go to 30k (real values are 22k and 33k Radio
Shack) (ham shop - other electronic source.)

If the lamp is still to dim with a 20k then put a 30k and 20k in
parallel and insert this pair into the line and see if the bulb brightens.

Start big and work downward for the brightness needed. LIkely 20k.

If you need help - I can do it for you easily.

Martin

On 5/26/2013 9:51 AM, janders wrote:
Hi Don,

The bulb itself simply screws into any standard light socket and
operates directly on 120v. There are no electronics whatever in the base
of the bulb. I posted a link to a place I found that sells them (though
I'd never seen them before buying this one used, they are not as rare as
I thought).

Thought hit me last night to do some searching on google.au, someone
might be making these to run directly on 220 down there. That would make
the whole voltage conversion moot. I was looking into that thinking I
had something rather unusual and a bit rare.

Jon

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Default Bit OT, compact, low current 220/110 step down transformer?


James Waldby wrote:

On Sun, 26 May 2013 07:51:01 -0700, janders wrote:
The bulb itself simply screws into any standard light socket and
operates directly on 120v. There are no electronics whatever in the base
of the bulb. I posted a link to a place I found that sells them (though
I'd never seen them before buying this one used, they are not as rare as
I thought).

Thought hit me last night to do some searching on google.au, someone
might be making these to run directly on 220 down there. That would make
the whole voltage conversion moot. I was looking into that thinking I
had something rather unusual and a bit rare.


You probably could run two of the 120v decorative bulbs in series
on 240v, or if you know the wattage of the decorative bulb, run one
in series with an incandescent bulb of the same wattage. Of
course if either bulb burns out both of them turn off.



You can't use a neon lamp in series with an incandescent lamp. the
current is too low for the incandescent lamp, and its resistance is too
low for the neon lamp. Measure the current it draws, and calculate the
required resistance needed to double the line voltage. It isn't double
the resistance used for 120, since the voltage drop across the neon is
60 to 90 volts.


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Default Bit OT, compact, low current 220/110 step down transformer?

In article , John G
wrote:

Joe Gwinn explained :
In article , John G
wrote:

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power transformer
rated for 6-10VA with a center-tapped 220V primary would do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for
a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn

The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).

Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.

Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.


So, you have four large non-green wires coming into your home?


Yes


OK.

Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is coming up to the harmonized 230
I believe.


I did find stuff about this voltage harmonization on the web.


Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?

Do not think there is any general use of Corner grounds at any level in
Aus.


OK. Perhaps I'll recall where I saw this claimed. I think it was in a
thread on RCM, some years ago. RCM folk were jealous of the Aussies
for having access to three-phase power in homes.


I can understand the jealousy but I think they were wrong or ill
informed about Corner grounds.


OK. That's why I asked.


In fact all, in my relativly wide
experience, houshold distribution is 4 wire WYE 240/415 volts in Aus
With only one phase delivered unless there is a larger load.
Remember a lot of Aus has a rather mild climate with a large proportion
living below the snow line or below the Tropic of Capricorn so it is
only in more recent times that Air Cons hve become very popular and
Dryers work fine on one 2Kw service 240 volts 10 amps.


I assume that there is a price difference. How available is the
three-phase service for say a home shop sans air conditioner?

Joe Gwinn
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Default Bit OT, compact, low current 220/110 step down transformer?

On Fri, 24 May 2013 11:18:05 -0700, janders wrote:

On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

I couldn't be sure without seeing it, but that sounds like a gas-
discharge lamp (like a neon bulb, but perhaps a gas blend that gives a
different color).

If so, you need only a limiting resistor.


Picture's worth a thousand words... G
https://picasaweb.google.com/lh/photo/

HR9gnIj6F9INyHaO0T1HqtMTjNZETYmyPJy0liipFm0?feat=d irectlink

Doubt highly there's any electronics involved. So, for an electronics
idiot, would you mind explaining a bit more on current limiting
resistors for something like this? I assume it'll have to dissipate
heat. Might it get hot enough that using part of the base as a heat sink
could result in a burn? But I like the idea of something as simple as a
resistor, make it a lot easier to hide in the base.

This won't be run all the time, just for effect now and then, maybe few
hours at a time.

Or is the small power transformer a better way to go?


A gas discharge lamp like what's inside of that runs at pretty much a
constant voltage, lower than 120V, and can accept a moderately wide range
of input currents. So it "wants" to see a source that can supply a wide
range of voltages and a fairly constant input current.

Wall power is a fairly constant voltage that will supply just about any
current that you ask of it, until the breaker pops. So it's exactly the
reverse of what the lamp needs.

The easy way to turn wall power into something that a gas discharge lamp
can handle is to use a resistor in series with the lamp. That lamp
almost certainly has just that sort of resistor in its base.

If you knew the current draw of the lamp when it's running from 120V this
would be easy -- you'd just need a resistor that would drop 100V at that
current, and had a power rating sufficient to burn up the lost energy
without overheating.

Were it me, I'd measure the AC current draw, then calculate a resistance
from R = (100V) / (current in amps), then go buy one that's close. I'm
expecting that the lamp will pull 10mA to 50mA, which means it'll be a
large resistance, probably around 4k-ohm to 20k-ohm. I'd also calculate
the power dissipation needed, P = (100V) * (current in amps). If I'm
right about the current, then it'll be in the one to five watt range.

Then I'd order parts on line or buy enough resistors from Radio Shack to
make up a string of the right dissipation and resistance.

But -- that's only easy if you already know your way around electronics.
If you don't it's way freaking complicated. An autotransformer will be
far heavier and proportionally far more expensive, but it's "more
expensive" as in dollars instead of dimes, it should be way simpler and
it should only be a couple of inches on a side at most.

Get one that has a 220V/120V primary. You don't care about the secondary
voltage -- you won't be using it. Hook it up like Lloyd says, ignore the
secondary (well, tape it off), and have fun.

Or, get one of the travel transformers and just use it. Hook it up, plug
it in, run it for an hour, then unplug and check the transformer -- if
its cool enough that you can hold it comfortably, then you're probably
OK. If you're feeling paranoid, do the same test again but leave it
plugged in for twelve hours or a day -- that'll get it as warm as its
going to get, and if it's still just warm and not hot then you're
probably OK.

If it does get hot, then find one with a higher current rating and try
again.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com
  #38   Report Post  
Posted to rec.crafts.metalworking
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Posts: 170
Default Bit OT, compact, low current 220/110 step down transformer?

Joe Gwinn brought next idea :
In article , John G
wrote:

Joe Gwinn explained :
In article , John G
wrote:

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power
transformer rated for 6-10VA with a center-tapped 220V primary would
do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at the
substation, and live is one leg of the 3 phase distribution system for
a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn

The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).

Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.

Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.

So, you have four large non-green wires coming into your home?


Yes


OK.

Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is coming up to the harmonized 230
I believe.

I did find stuff about this voltage harmonization on the web.


Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?

Do not think there is any general use of Corner grounds at any level in
Aus.

OK. Perhaps I'll recall where I saw this claimed. I think it was in a
thread on RCM, some years ago. RCM folk were jealous of the Aussies
for having access to three-phase power in homes.


I can understand the jealousy but I think they were wrong or ill
informed about Corner grounds.


OK. That's why I asked.


In fact all, in my relativly wide
experience, houshold distribution is 4 wire WYE 240/415 volts in Aus
With only one phase delivered unless there is a larger load.
Remember a lot of Aus has a rather mild climate with a large proportion
living below the snow line or below the Tropic of Capricorn so it is
only in more recent times that Air Cons hve become very popular and
Dryers work fine on one 2Kw service 240 volts 10 amps.


I assume that there is a price difference. How available is the
three-phase service for say a home shop sans air conditioner?

Joe Gwinn


I have no idea of the installation cost but 3 phase is available
everywhere except the rare cases where SWER is used.
Single phase houses are shared among the 3 phases.
It came bundled with an Aircon at my last house and it was at the
current one from its build in 1988.
There is no special billing. as far as I can see. the bill just shows
total Kw measured in my case by an old turning wheel 3 ph meter.

--
John G


  #39   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 416
Default Bit OT, compact, low current 220/110 step down transformer?

In article , John G
wrote:

Joe Gwinn brought next idea :
In article , John G
wrote:

Joe Gwinn explained :
In article , John G
wrote:

Joe Gwinn expressed precisely :
In article , John G
wrote:

Joe Gwinn has brought this to us :
In article , David Billington
wrote:

On 24/05/13 19:29, janders wrote:
On 5/24/2013 8:47 AM, Lloyd E. Sponenburgh wrote:

Likely, the current is low. Most "neons" pass only low tens of
milliamps, max. If that's the case, most any small power
transformer rated for 6-10VA with a center-tapped 220V primary
would
do.

Use it in "autoformer" mode, hooking 220V to the outside leads, and
tapping 110V from the line-neutral leg to the center leg.

Ok, just to make sure bases are covered, I've been told that in
Australia, 220 is -220-, either leg to ground is 220, not 110.
Don't know if that changes anything you wrote above...


Jon
I would expect Australia to be like the UK so you would have live,
neutral and ground, where neutral and ground are tied together at
the
substation, and live is one leg of the 3 phase distribution system
for
a
single phase supply. So you would get 220V from live to ground or
neutral, neutral to ground should be 0V but might have a small
difference but it should be very small.

I have heard that the difference is that Aussies distribute three
phase
corner-grounded delta even to residences, so simple voltage
measurements don't add up as expected because the wires are out of
phase with one another.

However, I have not been able to find any web cites to back this up.
Perhaps there is an Australian on the group who knows the details.

Joe Gwinn

The Australian System of High voltage is 3 phase Delta (ungrounded I
think). The local distribution is 3 phase WYE with the neutral center
of the WYE grounded so a single phase device is connected any phase
and
neutral giving a nominal of 240 volts (Although there is a move to the
harmonization as in Europe to 230 volts).
Three phase WYE is distributed to many homes (mine included ) giving
415 volts phase to phase for air con etc.
As I said elsewhere in this thread I generally get 245 or more as I am
the first drop of a 400kva pole pig ( bigger than most US pole pigs).

Three-phase wye requires 3 wires plus neutral plus ground (green or
bare), versus 2 wires plus neutral plus ground for the US and European
systems, and for corner-grounded 3-phase delta systems.

Three phase generally is only run to homes with big Air cons etc and
lower current (at higher voltage) needs less copper.

So, you have four large non-green wires coming into your home?

Yes


OK.

Europe is 3 phase WYE with the center grounded although the nominal
Volts was lower than Aus and UK but is coming up to the harmonized 230
I believe.

I did find stuff about this voltage harmonization on the web.


Is the corner-grounded 3-phase delta system possibly used in rural
areas of Australia?

Do not think there is any general use of Corner grounds at any level in
Aus.

OK. Perhaps I'll recall where I saw this claimed. I think it was in a
thread on RCM, some years ago. RCM folk were jealous of the Aussies
for having access to three-phase power in homes.

I can understand the jealousy but I think they were wrong or ill
informed about Corner grounds.


OK. That's why I asked.


In fact all, in my relativly wide
experience, houshold distribution is 4 wire WYE 240/415 volts in Aus
With only one phase delivered unless there is a larger load.
Remember a lot of Aus has a rather mild climate with a large proportion
living below the snow line or below the Tropic of Capricorn so it is
only in more recent times that Air Cons hve become very popular and
Dryers work fine on one 2Kw service 240 volts 10 amps.


I assume that there is a price difference. How available is the
three-phase service for say a home shop sans air conditioner?

Joe Gwinn


I have no idea of the installation cost but 3 phase is available
everywhere except the rare cases where SWER is used.
Single phase houses are shared among the 3 phases.
It came bundled with an Aircon at my last house and it was at the
current one from its build in 1988.
There is no special billing. as far as I can see. the bill just shows
total Kw measured in my case by an old turning wheel 3 ph meter.


OK. Thanks. I knew we had reason for jealousy.

Joe Gwinn
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