REQ: Info on neon light transformers
Adam Mikolajczyk
the required neon transformer. I would like any info anyone has on
where these could be found and approx how much I could expect to spend
on one. An information unlimited catalog carries a HV mini neon
transformer for $9.50 No other stats were given. I was intending to
purchase this if it were suitable. Any info anyone could offer, I
would greatly appreciate.
Thanks,
Adam J. Mikolajczyk
aj...@cornell.edu
TERRY DEWICK
-> I would like to construct a Jacob's Ladder generator and need
-> the required neon transformer. I would like any info anyone has on
-> where these could be found and approx how much I could expect to spend
-> on one. [cut]
Hate to say it but a Neon transformer will NOT work, it cannot supply the
required current and will burn out, or blow its internal fuse.
Terry
Bill Claussen
Not true Terry. I have built several over the years, using a neon sign
transformer, and they all worked fine(could get a 5-6in spark at the top).
Adam,
I used to go to a sign installer and ask them if they had any used or
shorted transformers, the biggest size they made. The shorted ones usually
only had a few turns shorted so instead of putting out 15kv, they might only
put out 13kv, but still worked fine. I used to pay about $1.00 for these.
good luck,
bill
James Foster x2912
|> aj...@cornell.edu (Adam Mikolajczyk) writes:
|>
|>
|> -> I would like to construct a Jacob's Ladder generator and need
|> -> the required neon transformer. I would like any info anyone has on
|> -> where these could be found and approx how much I could expect to spend
|> -> on one. [cut]
|> Hate to say it but a Neon transformer will NOT work, it cannot supply the
|> required current and will burn out, or blow its internal fuse.
All things are relative. I doubt that a $9.95 transformer will
work, but I've got a ~20 year old sign transformer that weighs about
30 lbs. and runs a jacobs ladder just fine for extended periods of
time. Don't recall what the secondary is off hand, but probably about
15kv. If I recall (this thing just gets pulled out occasionally on
Halloween - it was a quick afternoon hack to put it together) the max
gap it will run is about 3.5" and the bottoms of the "arms" (copper
plated welding rods) need to be pretty close together to get a
consistant start.
Steve Roys
> -> the required neon transformer. I would like any info anyone has on
> -> where these could be found and approx how much I could expect to spend
> -> on one. [cut]
> Hate to say it but a Neon transformer will NOT work, it cannot supply the
> required current and will burn out, or blow its internal fuse.
A neon SIGN transformer will work fine for a Jacob's ladder. They are
internally current limited (magnetic shunt) and should not burn out,
even with a direct short. You can look in your yellow pages under
"Signs, neon" and make some calls...someone somewhere will have
some used transformers for sale. You can expect to pay about $20-$30 for
a used but working 15kV, 30mA neon sign transformer.
Enjoy yourself, but be REAL careful...a 60 Hz shock from a neon sign
transformer can can ruin your whole day. Of course, your next logical step
is to graduate to Tesla coils...they're at least a couple of orders of
magnitude more fun, and not a whole lot more complicated (at least until
you get into the multi-kilowatt range).
Chris Matthaei
>aj...@cornell.edu (Adam Mikolajczyk) writes:
>
>
>-> I would like to construct a Jacob's Ladder generator and need
>-> the required neon transformer. I would like any info anyone has on
>-> where these could be found and approx how much I could expect to spend
>-> on one. [cut]
>Hate to say it but a Neon transformer will NOT work, it cannot supply the
>required current and will burn out, or blow its internal fuse.
>
>Terry
What are you talking about? I used an old neon sign transformer to make a
Jaccob's ladder. The output was 7600V at 5ma or something. It worked just
fine! A little more voltage for a longer spark would have been nice, though.
Chris
Hangar17
heavy duty transformer. Please be VERY careful. The voltage and current
out of some of these xfmrs could be lethal. Also, the ladder will
generate LOTS of ozone, good for the stratosphere, not so good for you.
TERRY DEWICK
-> TERRY DEWICK (dew...@brbbs.brbbs.com) wrote:
-> : aj...@cornell.edu (Adam Mikolajczyk) writes:
-> :
-> :
-> : -> I would like to construct a Jacob's Ladder generator and need
-> : -> the required neon transformer. I would like any info anyone has on
-> : -> where these could be found and approx how much I could expect to spend
-> : -> on one. [cut]
-> : Hate to say it but a Neon transformer will NOT work, it cannot supply the
-> : required current and will burn out, or blow its internal fuse.
-> :
-> : Terry
-> :
->
-> Not true Terry. I have built several over the years, using a neon sign
-> transformer, and they all worked fine(could get a 5-6in spark at the top).
->
-> Adam,
-> I used to go to a sign installer and ask them if they had any used or
-> shorted transformers, the biggest size they made. The shorted ones usually
-> only had a few turns shorted so instead of putting out 15kv, they might only
-> put out 13kv, but still worked fine. I used to pay about $1.00 for these.
->
-> good luck,
-> bill
Did not mean to say none would work, yes a large one will but the $10 variety
will not handle the load, best bet is a neon sign man for a used one.
David D. Lee
>A neon SIGN transformer will work fine for a Jacob's ladder. They are
>internally current limited (magnetic shunt) and should not burn out,
>even with a direct short.
Steve-
How does a magnetic shunt work? How well is current limited?
-dave
Sam Goldwasser
> I would like to construct a Jacob's Ladder generator and need
> the required neon transformer. I would like any info anyone has on
> where these could be found and approx how much I could expect to spend
> on one. An information unlimited catalog carries a HV mini neon
> transformer for $9.50 No other stats were given. I was intending to
> purchase this if it were suitable. Any info anyone could offer, I
> would greatly appreciate.
Depends on the voltage and current.
> Thanks,
> Adam J. Mikolajczyk
> aj...@cornell.edu
You will need 12K-15K volts AC (50/60) Hz at say 20-30 mA. A neon sign
(luminous tube) transformer is the usual source though an oil burner ignition
transformer will work in a pinch or you could build an inverter type power
supply.
When I did this many years ago, I got mine for about $7.50 from a sign
shop. It was used, pretty icky on the outside but worked fine. New ones
are expensive.
Take a pair of thick wires - the steel wire from old metal coat hangers works
pretty well - straighten them out and mount them with a gap of about 1/4
inch at the bottom and 1-2 inches at the top. Of course, all on an insulated
non-flammable material! Connect the high tension output of the transformer
to the two wires and you should be all set. Some adjustment of the
spacing may be required.
__ 1-2"
^ \ /
2-3 feet \ /
or more | \ /
v --| |---
1/4"
A jacob's ladder works on the principle that the ionized air in the arc
is a lower resistance than the air around it and heated air rises. The
arc strikes at the point of lowest breakdown voltage - the small gap
at the bottom. The heated plasma rises and even when it is an inch or
more in width is an easier path for the current to follow. Eventually,
the gap becomes two wide, the arc extinguishes and is reestablished
at the bottom. For best results, shield the whole thing from drafts but
don't use anything that can catch fire!
Safety:
Make sure that no one can come in contact with this - particularly curious
onlookers. Separating the potential victims from any possible contact
with the high voltage is really the only foolproof way of protecting
against fools or the unaware - and you from a lawsuit.
A GFI (ground fault interrupter) is of no use in protecting against HV
contact since the secondary of a neon sign transformer is isolated from the
line but its centertap is usually connected to the case - which should be
grounded. However, a GFI would be a good idea in any case when you are
working with line connected equipment.
12,000 volts will jump approximately 1/2-3/4 inch in dry air - more under
humid conditions. Don't forget that 12,000 VAC is approximately 17,000 V
peak. Neon sign transformers have current limited outputs - 30 mA is
typical - but that is still highly dangerous - lethal under the wrong
conditions.
You can build a small Jacob's Ladder using a high voltage transformer
of lower capacity or a DC-AC inverter using a TV flyback transformer.
While these would be less dangerous, there is little room for carelessness
when working with high voltage. Even if there is no resistive path,
the stray capacitance can permit enough AC current to flow to give you
a painful experience!
* Do not work alone.
* Always keep one hand in your pocket when anywhere around a powered
line-connected or high voltage system.
* Wear rubber bottom shoes or sneakers.
* Don't wear any jewelery or other articles that could accidently contact
circuitry and conduct current.
* Use an isolation transformer if there is any chance of contacting line
connected circuits.
* Don't make adjustments with power on.
* Finally, never assume anything without checking it out for yourself!
Don't take shortcuts!
--- sam
Sam Goldwasser
> aj...@cornell.edu (Adam Mikolajczyk) writes:
> -> I would like to construct a Jacob's Ladder generator and need
> -> the required neon transformer. I would like any info anyone has on
> -> where these could be found and approx how much I could expect to spend
> -> on one. [cut]
> Hate to say it but a Neon transformer will NOT work, it cannot supply the
> required current and will burn out, or blow its internal fuse.
> Terry
Neon sign or luminous tube transformers ARE the usual way to drive a Jacobs
Ladder. They are internally current limited due to the design of their
magnetic components. The most common size is 12-15KV at 30 mA. Try sign
shops for good deals on used transformers.
There have been ample postings on the design of Jacobs ladders and the
very important safety precautions.
--- sam
RiK
: |> aj...@cornell.edu (Adam Mikolajczyk) writes:
: |>
: |>
: |> -> I would like to construct a Jacob's Ladder generator and need
: |> -> the required neon transformer. I would like any info anyone has on
: |> -> where these could be found and approx how much I could expect to spend
: |> -> on one. [cut]
: All things are relative. I doubt that a $9.95 transformer will
: work, but I've got a ~20 year old sign transformer that weighs about
: 30 lbs. and runs a jacobs ladder just fine for extended periods of
: time. Don't recall what the secondary is off hand, but probably about
: 15kv. If I recall (this thing just gets pulled out occasionally on
: Halloween - it was a quick afternoon hack to put it together) the max
: gap it will run is about 3.5" and the bottoms of the "arms" (copper
: plated welding rods) need to be pretty close together to get a
: consistant start.
I've got one here that sounds a lot like yours. It's a 15kv, 30mA
xformer using two coat hangers for the ladder. The bottom of the ladder
is 3/8" apart, with the top at 1 3/4", and the whole thing being about
29" tall. If I remember to turn my fan off :), that spark travels nicely
all the way to the top.
You can also make an interesting one using two peices of wire and
stringing them from the floor to your ceiling, with similar begin and end
measurements, and get a spark to travel seemingly in mid-air (because the
wire is difficult to see..). Take care with this tho, I have seem (or
easily imagined) the following problems: 1- setting your ceiling on
fire. Make sure you protect it somehow or make sure the spark can't get
that high. 2- someone wanting to get a closer look at the device can
easily hit the wire since it may be hard to see. 3- the wire may burn
through from the heat from the spark, and then fall pretty much
anywhere... Like on something metal/electronic, or you. It's an
interesting project, but can be _very_ dangerous.
Rik
Soundwave
>Did not mean to say none would work, yes a large one will but the $10 variety
>will not handle the load, best bet is a neon sign man for a used one.
>
While I have known all along that neon sign transformers make
good power supply transformers for Tesla Coils, Jacob's Ladders and the
like, I have never used them. My grandfather is a plumbing/heating guy
with an ample supply of 10kVAC/23ma Oil Burner transformers, and these were
always the most readily available solution. Are there any important
differences in these two types of transformers?
-Adam
+----------------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical and
Computer Engineering
<Audio Signal Processing>
+----------------------------------------------------------------------------+
IJBU TRIAD
>
> I would like to construct a Jacob's Ladder generator and need
>transformer for $9.50 No other stats were given. I was intending to
>purchase this if it were suitable. Any info anyone could offer, I
>would greatly appreciate.
>
I am also looking for a neon light transformer. I want one to use as
the line transformer in a tesla coil. Most are 12kv @ 30 mA. I have
checked with a couple sign shops in my area, and have found new ons
cost $50 up. I would guess a $10 transformer would be a bit light
for a Jacob's ladder.
Glen Ray
robert rader
>On neon sign xformers:
>>Did not mean to say none would work, yes a large one will but the $10 variety
>>will not handle the load, best bet is a neon sign man for a used one.
>>
> While I have known all along that neon sign transformers make
>good power supply transformers for Tesla Coils, Jacob's Ladders and the
>like, I have never used them. My grandfather is a plumbing/heating guy
>with an ample supply of 10kVAC/23ma Oil Burner transformers, and these were
>always the most readily available solution. Are there any important
>differences in these two types of transformers?
>-Adam
Yes a big difference.
the oil burner is designed for light duty! Not continous use.
The best transformers for ladders etc.are the larger end Flourescent ballast
transformers . Not the neons. Neons are typically a low current spec.
The higher end Flourescents run around 150 and can give a good 25k at a
continuous current that is usable without damaging the transformer.
I found all this thru experience. Sometimes she can be a very expensive
teacher!
Your Friend
Robert Rader
lo...@teleport.com
Steve Roys
> >On neon sign xformers:
>
> > While I have known all along that neon sign transformers make
> >good power supply transformers for Tesla Coils, Jacob's Ladders and the
> >like, I have never used them. My grandfather is a plumbing/heating guy
> >with an ample supply of 10kVAC/23ma Oil Burner transformers, and these were
> >always the most readily available solution. Are there any important
> >differences in these two types of transformers?
>
> >-Adam
>
I don't think there is any appreciable difference. They are both
high-voltage, current limited transformers that have been used to
power Jacob's ladders and Tesla coils. If you have a ready supply of
them, GO FOR IT (we should all be so lucky). Just remember to be
CAREFUL, 60Hz current can KILL YOU REAL QUICK, and 10kV will jump for you.
> Yes a big difference.
> the oil burner is designed for light duty! Not continous use.
> The best transformers for ladders etc.are the larger end Flourescent ballast
> transformers . Not the neons. Neons are typically a low current spec.
> The higher end Flourescents run around 150 and can give a good 25k at a
> continuous current that is usable without damaging the transformer.
Methinks you might be mistaken. The ballast in a fluorescent light is
not a transformer in the sense of a neon sign or oil burner transformer.
It's pretty much an inductor that:
1. Gives a momentary high-voltage, low-current kick to the tube to get
the gas conducting after the starter heats the filaments and cuts out, and
2. Limits the current to the tube so it doesn't fail after it starts
conducting.
You simply can't get high voltage, high current out to drive a Jacob's
ladder or Tesla coil from a fluorescent lamp ballast. Neon sign
transformers can typically be had with a working voltage up to 15kV and
current ratings up to 120 mA, and work just fine for Jacob's ladders and
Tesla coils. Oil burner transformers will also work although they are
typically lower current so you have to gang them up in parallel for
higher currents.
air...@merlin.nando.net
> >
My grandfather is a plumbing/heating guy
> > >with an ample supply of 10kVAC/23ma Oil Burner transformers, and
these were
> > >always the most readily available solution.
> >
>
I've used a oil burner transformer to construct a jacob's ladder.
It worked fairly well, producing an arc of about 1 inch at its top.
And while the transformer did run rather warmly after a short time,
how long can one stare a jacob's ladder? Its not like you plan to
cook steaks on the thing. -AIRWICK
Frank Boddeke
All this talk about Jacob's ladder. Now we want to see prove. How can we
make one? neon-light transformers? Is that the same as in a TL-lamp? This
transformer has only two leads.
Anyone?
Thanks,
The Fryday-afternoon Project
Frank and Michiel
Soundwave
Frank Boddeke <bod...@ph.tn.tudelft.nl> wrote:
>Hi There,
>
>All this talk about Jacob's ladder. Now we want to see prove. How can we
>make one? neon-light transformers?
You can make small Jacob's ladders with neon-light transformers, but they
have a magnetic shunt current-limiting system to protect the transformer
from damage due to shorting. This current-limiting severly affects the
performance of the Jacob's ladder. Best thing is to un-pot the x-former
and remove a few layers from the shunting core pieces, or try a few
transformers until you find one that works well.
My 10kV/23mA oil burner transformers (Jefferson & Webster models) make MUCH
better Jacob's ladders that any of my 15kV/30mA Franceformer brand neon
units because they have less shunting.
>Is that the same as in a TL-lamp?
What's a TL-Lamp?
Steve Roys
> transformer has only two leads.
> Anyone?
I'm not sure what a TL-lamp transformer is, but a neon sign transformer
is a high-voltage step up transformer used to energize NEON SIGNS (NOT
fluorescent lights). It will take in house current and put out 9000V to
15000V at a current rating of 15mA to 120mA depending on the model. It
has an internal magnetic shunt to limit the current, and the center-tap
of the high-voltage side is grounded to the case. The low-voltage side
has two hot wires and the center ground for the case. The high-voltage
side usually is wired to two ceramic bushings sticking out of the side of
the transformer.
To find one, look in your phone book for sign companies, and then look
for one that services or installs neon signs. It's very probable that
they would sell you a used 15kV, 30mA to 60mA transformer for around $30.
R. D. Davis
> I've used a oil burner transformer to construct a jacob's ladder.
Me too... now I've got to find a use for the rest of the old oil-burner
assembly... perhaps it could just turn into a restoration project to be
used when the newer unit wears out. :-)
> It worked fairly well, producing an arc of about 1 inch at its top.
> And while the transformer did run rather warmly after a short time,
> how long can one stare a jacob's ladder? Its not like you plan to
> cook steaks on the thing. -AIRWICK
In order to prevent that sort of overheating, etc., it's useful to
connect a motion sensor and some time-delay AC power switching
apparatus to the Jacob's ladder. About 10 years ago, I bought one of
those Radio Shack ultrasonic motion detectors and then rigged up a
small circuit using a 555 timer, 2 relays and a few other misc. parts.
When the motion detector detects motion, it triggers the 555 circuitry
which keeps the AC power controlling relay closed for a variable
abount of time which can be adjusted by a trimmer pot. I originally
designed it to control floodlights, but it works great for this
purpose as well.
This is very useful for having fun with visitors on Halloween! :-) As
soon as they step onto the porch, zap, crackle, pop! If they stand
still, it stops after 10 seconds or so... as soon as they move, it
starts again.
One other thing... instead of using wire for the spark to travel on, I
got some steel (couldn't find copper at the time) rods that were
between 3/32 and 1/8 of an inch or so in diameter and about a yard
long from the hardware store.
--
R. D. Davis
rda...@umbc.edu, r...@mystica.uucp
Home telephone: 1-410-744-7964
http://www.access.digex.net/~rdd
Sam Goldwasser
RE: Jacobs Ladders and Halloween. Just as long as you realize that
the voltages and currents involved are extremely dangerous. Any
public display must be guaranteed to be separated from possible
contact by the curious or careless. You have both line voltage
and high voltage and either one can kill under the wrong circumstances.
--- sam
R. D. Davis
Sam Goldwasser <s...@colossus.stdavids.picker.com> wrote:
>In article <3qoi18$p...@umbc8.umbc.edu> rda...@umbc.edu (R. D. Davis) writes:
>RE: Jacobs Ladders and Halloween. Just as long as you realize that
>the voltages and currents involved are extremely dangerous. Any
Yes, I realize that.
>public display must be guaranteed to be separated from possible
>contact by the curious or careless. You have both line voltage
>and high voltage and either one can kill under the wrong circumstances.
Hence, I keep the Jacob's ladder a reasonable distance from the door
where the trick or treaters would be, with a barrier of branches and
various other things to keep a very safe distance between the Jacob's
ladder and anyone who approaches the front door. I don't someone
wandering over and disturbing my jacobs ladder... getting that
spark-gap set just right isn't exactly easy... of course, last year it
was rather humid and the fluctuations in the humidity (it started to
rain a few times, but each time it there were only a few minute
sprinkles of rain) kept me running out to reset the spark gap every
half-hour or so.
If you want to make the effects even better, keep all of the lights in
the house turned off, put a somewhat dim black-light bulb in the porch
lamp socket, roam about first floor of the house, looking out the
windows, carrying a lit candlestick. When someone knocks at the door,
slowly go to the door carrying the candlestick. I think that the
combination of the eerie way I said "Good evening" and my overgrown
beard helped to spook quite a few people. :-)
Back to Jacob's ladders... I've found that one can also create some
rather interesting effects using window screen material, etc. Just be
careful! Aside from getting zapped, you can even do some damage to
yourself when it's unplugged, as some parts where the spark travels
can become rather hot.
Sam Goldwasser
> Hi There,
> All this talk about Jacob's ladder. Now we want to see prove. How can we
> make one? neon-light transformers? Is that the same as in a TL-lamp? This
> transformer has only two leads.
> Anyone?
A neon sign transformer or luminous tube transformer is usually about
12-15KV at 15-60 mA, quite enough for a decent Jacobs Ladder (and to kill
you as well).
> Thanks,
> The Fryday-afternoon Project
> Frank and Michiel
A basic Jacobs Ladder:
You will need 12K-15K volts AC (50/60) Hz at say 20-30 mA. A neon sign
(luminous tube) transformer is the usual source though an oil burner ignition
transformer will work in a pinch or you could build an inverter type power
supply.
Take a pair of thick wires - the steel wire from old metal coat hangers works
R. D. Davis
In article <SAM.95Ju...@colossus.stdavids.picker.com>,
Sam Goldwasser <s...@colossus.stdavids.picker.com> wrote:
>Take a pair of thick wires - the steel wire from old metal coat hangers works
>pretty well - straighten them out and mount them with a gap of about 1/4
Better yet, get two steel rods, nearly a yard long, from a hardware
store. The hardware store that sells the rods should also be able to
sell you clamps that can be used to connect the HV wires to... the
clamps that I used also made a good spark-gap.
>inch at the bottom and 1-2 inches at the top. Of course, all on an insulated
>non-flammable material! Connect the high tension output of the transformer
It can be safely mounted on wood; just place some aluminum foil, or
somesuch, between the wood and the spark.
>at the bottom. For best results, shield the whole thing from drafts but
>don't use anything that can catch fire!
Why take all the fun out of things by shielding it from drafts? A
slight draft makes the rising spark look a bit more interesting at
times. I realize that if it's not set up just right, a small draft
can stop it from working, but them, a change in humidity can also stop
it from working until the spark-gap is reset.
>Safety:
What is this, sci.electronics, or ralph.naders.safety.electronics? :-)
Can't people just use their own common sense?
>Make sure that no one can come in contact with this - particularly curious
>onlookers. Separating the potential victims from any possible contact
>with the high voltage is really the only foolproof way of protecting
>against fools or the unaware - and you from a lawsuit.
Well, who in their right mind is going to stick their finger into a
big blue spark? Certainly one should be very careful when very young
children, pets and people who are mentally-ill or senile can get near
it, but the average person, including children over 6 or so years old,
should know better than to stick their finger there and get
ZZZzzzappppped.
>grounded. However, a GFI would be a good idea in any case when you are
>working with line connected equipment.
Isn't that going a bit overboard?
>12,000 volts will jump approximately 1/2-3/4 inch in dry air - more under
>humid conditions. Don't forget that 12,000 VAC is approximately 17,000 V
>peak. Neon sign transformers have current limited outputs - 30 mA is
>typical - but that is still highly dangerous - lethal under the wrong
>conditions.
I think this is rather obvious.
>* Do not work alone.
Why? If being careful, I see no outstanding danger in workign alone.
Should we also avoid using the stairs if no one else is at home?
Should we avoid taking showers or baths if no one else is at home
(bathtubs and tile floors can become quite slippery)? Should we also
avoid eating while alone? Should we not repair any televisions while
we are alone?
>* Don't make adjustments with power on.
Now even if using properly insulated tools???
Michael Starks
: A few comments... no flames intended:
No. These were flames.
: In article <SAM.95Ju...@colossus.stdavids.picker.com>,
: Sam Goldwasser <s...@colossus.stdavids.picker.com> wrote:
: >Safety:
: What is this, sci.electronics, or ralph.naders.safety.electronics? :-)
: Can't people just use their own common sense?
Often people forget just how dangerous high voltages can be, even
if just for a moment. That moment can be enough to kill you. We
all need to be reminded of the "obvious", "common sense" safety
measures periodically so that when that moment comes we don't get
ourselves killed. The plasma lab I work in holds regular OSHA
safety seminars where they even tell you to look both ways when
you come out of the building to cross the street!
: >* Do not work alone.
: Why?
Because the extra risk is unnecessary. One jolt of HV could stop
your heart. Someone else nearby could administer CPR and save
your life.
: If being careful, I see no outstanding danger in workign alone.
: Should we also avoid using the stairs if no one else is at home?
No.
: Should we avoid taking showers or baths if no one else is at home
: (bathtubs and tile floors can become quite slippery)?
No.
: Should we also avoid eating while alone?
No.
: Should we not repair any televisions while we are alone?
Probably not. Again, it's often an unnecessary risk. especially
if you aren't a professional.
: >* Don't make adjustments with power on.
: Not even if using properly insulated tools???
Right. There is no adjustment to a Jacob's Ladder that is more
useful with the power on than with it off. There is no justification
for the extra risk of fiddling with it under high voltage conditions.
Shut it off, unplug it, and be careful!
To quote you, these things are rather obvious. While you are
free to do as you please, it's irresponsible to encourage others
to be unsafe around high voltages.
Yes, this was a flame. I'm sure there are a lot of professionals
and hobbyists alike who agree with me. OSHA and our local safety
professionals certainly do.
Michael Starks
Radio Communications and Plasma Physics Research Lab
Boston University College of Engineering
Versatile Toroidal Facility
Massachusetts Institute of Technology Plasma Fusion Center
Soundwave
>A few comments... no flames intended:
>
>Sam Goldwasser <s...@colossus.stdavids.picker.com> wrote:
>
>>pretty well - straighten them out and mount them with a gap of about 1/4
>>non-flammable material! Connect the high tension output of the transformer
>
>It can be safely mounted on wood; just place some aluminum foil, or
Huh? Where do you propose to put the aluminum foil such that it won't
short the transformer? I don't think this is necessary; just make your
wires like this: Not like this:
\ / \ /
\ / \ /
\ / \ /
__\ /__ \ /
| | ||
| | ||
This way, the spark starts well above the wood, and won't short THROUGH
the wood. Secondly, use DRY wood, don't just grab a fresh 2 by 4 from your
shop or chances are you'll burn a nice long carbon trace down the center,
see a lovely red glow followed by a fire, and never get the satisfaction of
seeing the ladder work.
>Why take all the fun out of things by shielding it from drafts? A
>slight draft makes the rising spark look a bit more interesting at
>times. I realize that if it's not set up just right, a small draft
>can stop it from working, but them, a change in humidity can also stop
>it from working until the spark-gap is reset.
Important! If you operate the ladder in an airtight column for any length
of time, vent it outdoors!!!! When you open the column and the air inside
turns a nice thick reddish brown, that's NO2 (Nitrogen Dioxide). The arc
combined N2 and O2 to make NO, which then oxidizes upon exposure to more
oxygen. This is very toxic, and can cause pulmonary edema in high
concentrations.
>>Safety:
>
>What is this, sci.electronics, or ralph.naders.safety.electronics? :-)
>Can't people just use their own common sense?
>Well, who in their right mind is going to stick their finger into a
>big blue spark?
My neighbor, a Chemical Engineer for one of the largest high-purity
silicon manufacturing cooperations in the world. Thought he
could pass his finger through the arc like it was a candle.
He is in his right mind, he's not senile, under 6, or stupid, he just
didn't think 60 thousandths of an Ampere was much current. Of course I
didn't let him try it...
>>12,000 volts will jump approximately 1/2-3/4 inch in dry air - more under
>>humid conditions. Don't forget that 12,000 VAC is approximately 17,000 V
>>peak. Neon sign transformers have current limited outputs - 30 mA is
>>typical - but that is still highly dangerous - lethal under the wrong
>>conditions.
>
>I think this is rather obvious.
That's nice that it's obvious to you, but as just noted, some people have
no concept of how much/how little current can kill someone.
>>* Do not work alone.
>
>Why? If being careful, I see no outstanding danger in workign alone.
>Should we also avoid using the stairs if no one else is at home?
>Should we avoid taking showers or baths if no one else is at home
>(bathtubs and tile floors can become quite slippery)? Should we also
>avoid eating while alone? Should we not repair any televisions while
>we are alone?
Should we not go diving alone? It is up to you to determine the risk.
Some people are accident prone. I work with a couple people who were
electrocuted (obviously not to death) from faultly 'safety' grounds on
equipment. GFI's could have saved them a lot of disability, but my point
is that they were not in a position to save themselves.
>>* Don't make adjustments with power on.
>
>Now even if using properly insulated tools???
Yes, not even with properly insulated tools. If one of those wires of
your Jacob's ladder comes loose and starts falling your way, your 3'
fiberglass adjustment tool may not be in the right place to help you out :-o
-Adam
+---------------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical
and Computer Engineering
<Audio Signal Processing and Other Fun Stuff>
+---------------------------------------------------------------------------+
Jonathan D. Feinberg
> >Safety:
>
> What is this, sci.electronics, or ralph.naders.safety.electronics? :-)
> Can't people just use their own common sense?
[snip]
> >12,000 volts will jump approximately 1/2-3/4 inch in dry air - more under
> >humid conditions. Don't forget that 12,000 VAC is approximately 17,000 V
> >peak. Neon sign transformers have current limited outputs - 30 mA is
> >typical - but that is still highly dangerous - lethal under the wrong
> >conditions.
>
> I think this is rather obvious.
You forget the newbies, like me, who appreciate thoroughness and an
emphasis on safety.
--
Jonathan "JD" Feinberg j...@panix.com Sunny Brooklyn
"C'est rate, c'est rate. Quand on s'enerve on rate toujours."
-- Albert Marcoeur
Walter Gray
>
>: In article <SAM.95Ju...@colossus.stdavids.picker.com>,
>: Sam Goldwasser <s...@colossus.stdavids.picker.com> wrote:
>
>: >Safety:
>
>: What is this, sci.electronics, or ralph.naders.safety.electronics? :-)
>: Can't people just use their own common sense?
>
>if just for a moment. That moment can be enough to kill you. We
>all need to be reminded of the "obvious", "common sense" safety
>measures periodically so that when that moment comes we don't get
>ourselves killed. The plasma lab I work in holds regular OSHA
>safety seminars where they even tell you to look both ways when
>you come out of the building to cross the street!
I hope you pay attention to your OSHA people. Where I work they
used to be a bit careless with vehicles. I came out of a corner door
and I looked round the corner 'cos I could hear an engine. Some fool
had just decided to show how easy it was to drive a tank round a corner
at 30mph.
still here though
walter
- - - - - - - - - - - - - - disclaimers - - - - - - - - - - - - - - -
R. D. Davis
>R. D. Davis (rda...@umbc.edu) wrote:
>: Can't people just use their own common sense?
>ourselves killed. The plasma lab I work in holds regular OSHA
>safety seminars where they even tell you to look both ways when
>you come out of the building to cross the street!
If it were up to OSHA, people who ride horses would have to equip
their horses with four OSHA-approved training wheels, blinking lights,
and a gun to use if the horse won't stop quickly enough.
>: Should we not repair any televisions while we are alone?
>
>Probably not. Again, it's often an unnecessary risk. especially
>if you aren't a professional.
^^^^^^^^^^^^
There's that damned "P" word again; I've know plenty if incompetent,
moronic, "professionals". On the other hand, I've known hobbyists who
are extremely competent and knowledgeable. You can't judge someones
ablity by whether or not they earn an income from something; to do so
would imply the the logic iof the average personnel department droid.
Michael Starks
: >R. D. Davis (rda...@umbc.edu) wrote:
: >: Should we not repair any televisions while we are alone?
: >
: >Probably not. Again, it's often an unnecessary risk. especially
: >if you aren't a professional.
: ^^^^^^^^^^^^
: There's that damned "P" word again; I've know plenty if incompetent,
: moronic, "professionals". On the other hand, I've known hobbyists who
: are extremely competent and knowledgeable. You can't judge someones
: ablity by whether or not they earn an income from something; to do so
: would imply the the logic iof the average personnel department droid.
Apologies for offending you with the "P" word. In this context
it refers to the accepted definition of "a person of competence in
a particular field, especially one with a great deal of experience".
: If it were up to OSHA, people who ride horses would have to equip
: their horses with four OSHA-approved training wheels, blinking lights,
: and a gun to use if the horse won't stop quickly enough.
They may seem this bad, but the kind of stupid injuries that show
up in industrial settings mandate it. And it's not just "incompetent,
moronic" types. Anybody is vulnerable to a moment's distraction
that will make them look "incompetent and moronic" -- especially
if they get hurt. Often, OSHA's tips protect you from "the other
guy", who isn't paying attention.
As an aside, in a more perfect world, easily half the people I
see out riding horses shouldn't be allowed near them. The animals
are reasonably safe, if you know what you are doing (i.e. if
you're a professional? ;-)
Regards,
Michael Starks
Radio Communications and Plasma Physics Research Laboratory
Boston University College of Engineering
Versatile Toroidal Facility
MIT Plasma Fusion Center
Bill Claussen
: They may seem this bad, but the kind of stupid injuries that show
: up in industrial settings mandate it. And it's not just "incompetent,
: moronic" types. Anybody is vulnerable to a moment's distraction
: that will make them look "incompetent and moronic" -- especially
...clip...
We have so many rules and laws to keep incompetent and moronic folks
from hurting themselves, that all were getting these days are
incompetent and moronic people.
Bill
Chris Yardley
Soundwave <smi...@forbin.syr.edu> wrote:
<snip>
>but it's the high current that keeps the plasma hot and makes the ladder
>really climb. Anybody who's done this experiment with a pole-pig knows
>exactly what I'm talking about.
You've gotta be kidding! A 12500 watt Jacob's Ladder? Can you say
"copper vapor poisoning" ? :)
--
Chris Yardley - jyar...@nyx10.cs.du.edu cyar...@mail.coin.missouri.edu
Tantric Lobotomy Commission - Video Art Brain Damage...
Art meets Technology at the border of Insanity! TLC Demo Video available.
Addt'l e-addresses: cyar...@cyberspace.org bp...@freenet.hsc.colorado.edu
Soundwave
Warren Gay VE3WWG <w...@coutts.COUTTS.ON.CA> wrote:
>
>...snip...re...neon-light transformers...
>
>Actually, a smaller and better solution IMO is the transformer from an
>old OIL FURNACE BURNER. The transformer is much smaller, say approx 4-6
>inches cubed, and the current levels are decidedly lower. Its a lot
>lighter for your kids to take to "show-and-tell", *OK*, only kidding
>there! The arc is probably smaller, but for home use it is sufficient.
>
>I recall that it works very well for Jacob's ladders, as I used one in
>high school many years ago for that very purpose. In fact, they are so
>conveniant for that because they have the two polarities come out at the
>"top" end (with unit turned on its side), that you can bolt two wires on
>with. Neaten the wires, and plug it in. FFfffiizzzzaaaaaapp!
Yes, the burner units are (with very few exceptions) designed to deliver
10,000V with current limited to around 23mA. These are a bit less
dangerous than 12kV - 15kV neon units, but may perform just as well in a
Jacob's ladder setup. As I think I mentioned earlier on this thread, my
10,000V/23mA Webster and Jefferson Oil Burner units make better ladders
than my 15,000V/30mA Franceformers (neon), but all these lose out to my
12,000V/60mA GE neon unit. Higher voltage is good to get things started,
but it's the high current that keeps the plasma hot and makes the ladder
really climb. Anybody who's done this experiment with a pole-pig knows
exactly what I'm talking about.
Another great thing about Oil burner transformers is the fact
that you can usually get them for free. I am accustomed to paying $20 to
$60 for a used neon transformer (price goes up with wattage and down with
age) but most plumbing/heating repair places part with used burner
jobs for nothing. Even better than an oil burner transformer are two in
parallel (note that phase must be matched); the 10,000V/46mA combination is
almost guaranteed to give great ladder performance at rock-bottom prices.
Hope this helps to inspire :)
-Adam
+---------------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical
and Computer Engineering
<Audio Signal Processing and recently, coiling>
+---------------------------------------------------------------------------+
Soundwave
Chris Yardley <jyar...@nyx10.cs.du.edu> wrote:
>In article <3s0bpn$4...@newstand.syr.edu>,
>Soundwave <smi...@forbin.syr.edu> wrote:
><snip>
>>really climb. Anybody who's done this experiment with a pole-pig knows
>>exactly what I'm talking about.
>
>"copper vapor poisoning" ? :)
No joke. From what I've heard, Tesla Coil builder Richard Quick even
shows this on his 2 hour video tape (ava. from him for $10 + new tape).
Pole pigs come in lots of sizes too, 5kVA, 10 kVA, 12.5kVA 15kVA ...
ad nauseum. Nothing says you have to run the pig at its full rated power
for this experiment either.
Of course you would not use coathanger wire as your ladder... :)
Steel rods/bar stock are probably the best choices.
-Adam
+----------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical and
Computer Engineering
<DSP and other fun stuff>
+----------------------------------------------------------------------+
Samuel M. Goldwasser
>> You've gotta be kidding! A 12500 watt Jacob's Ladder? Can you say
>>"copper vapor poisoning" ? :)
Right, and then you will explain to the nice power company that
you need an additional 50 A 240 service put in for your Jacobs
ladder. Probably should make that 100 A service to support the
Tesla coil under construction - always nice to allow for expansion.
--- sam
Bob Groschen
>
>In article <3s0bpn$4...@newstand.syr.edu>,
>Soundwave <smi...@forbin.syr.edu> wrote:
><snip>
>>but it's the high current that keeps the plasma hot and makes the ladder
>>really climb. Anybody who's done this experiment with a pole-pig knows
>>exactly what I'm talking about.
>
>"copper vapor poisoning" ? :)
At 12,500 watts, I'd like to see this dude's power bill..............:-)
--
Regards,
Bob Groschen (rpgro...@mmm.com)
Data Cartridge Systems Laboratory
Memory Technologies Division
3M Co.
Standard Disclaimers apply here -->[X]
-------------------------------------------------
Why does a _Slight_ tax increase cost you $200 and
a _Substantial_ tax cut save you $0.30?
Bob Groschen
[snip]
>Pole pigs come in lots of sizes too, 5kVA, 10 kVA, 12.5kVA 15kVA ...
>ad nauseum. Nothing says you have to run the pig at its full rated power
>for this experiment either.
Adam, I think you've got your figures confused: Now you're quoting
power in kVA units (and that's OK). That's a far cry from *watts*
Still a 15 kVA power transfer, at say 15,000 volts is still 1 amp
into a resistive load. Just how do you plan to power these things?
Don't tell me! Let me guess: You've got a portable peaking plant
on a flatbed trailer, just like those the local power company uses,
right? So tell me, just how much kerosene does the GE turbine on
that plant comsume in an hour?
>
>Of course you would not use coathanger wire as your ladder... :)
>Steel rods/bar stock are probably the best choices.
Especially since the power company wouldn't connect that much power
to anything less than a 000 AWG connection. :-)
Adam Felson
discussion on how to implement this.
Reminds me of a spec I saw for a part loading table for a 2 minute
process where the table was supposed to go 500rpm (should have been
5.00rpm)... Even thought the table would only index 1/12 a revolution
every two minutes, designs were drawn up with an automatic transmission
so that it could spin up to 500rpm. At that speed, parts would be flying
off and embedding themselves in the walls....
Soundwave
Adam Felson <afe...@rainbow.rmii.com> wrote:
>Typical engineers. Someone posts 12.5kw instead of 12.5kv and we get a
>discussion on how to implement this.
Typical non-engineers.
The debate was 12.5kW vs. 12.5kVA, big difference from kV!
^
In a rather perverse way, you've proved your point :)
-Adam
+-------------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical and
Computer Engineering
+-------------------------------------------------------------------------+
Soundwave
>In article <3s6uj7$e...@newstand.syr.edu>, smi...@forbin.syr.edu says...
>
>[snip]
>
>>Pole pigs come in lots of sizes too, 5kVA, 10 kVA, 12.5kVA 15kVA ...
>>ad nauseum. Nothing says you have to run the pig at its full rated power
>>for this experiment either.
>
>Adam, I think you've got your figures confused: Now you're quoting
>power in kVA units (and that's OK). That's a far cry from *watts*
>Still a 15 kVA power transfer, at say 15,000 volts is still 1 amp
>into a resistive load. Just how do you plan to power these things?
Bob, I was just noting that pole-pigs come rated for different amounts of
continuous power handling (without overheating), not on the comment about
the 12.5kW ladder spark. What part exactly are you objecting to?
>Don't tell me! Let me guess: You've got a portable peaking plant
>on a flatbed trailer, just like those the local power company uses,
>right? So tell me, just how much kerosene does the GE turbine on
>that plant comsume in an hour?
I use my substation truck for picnics, and rent it out for small concerts,
but I wouldn't use it for home experiments ;)
But seriously, you have to run the pig with some heavy primary-circuit
current limiting. People who run pigs backwards for Tesla use most often
have a current-limiting impedance that is both resistive and reactive.
For example, it is not uncommon to limit the pig's intake with a large
power-transformer sized inductance and a few electric burner coils (from
atop an electric range) to add the resistance needed to lighten the power-on
surge and preserve variac contacts.
>>Of course you would not use coathanger wire as your ladder... :)
>>Steel rods/bar stock are probably the best choices.
>
>Especially since the power company wouldn't connect that much power
>to anything less than a 000 AWG connection. :-)
They might on the high-voltage side. If you limit pig current
properly in the primary circuit, so that the Jacob's arc only pulls a few
hundred milliamps, you don't need much more than 12 AWG from
pig-to-ladder to be quite safe. I would suggest uninsulated wire, since
heat from the ladder's spark is much more likely to heat the wire
locally than current flow is (heat from arc => melted wire insulation).
Hope this helps clear things up some...
-Adam
+---------------------------------------------------------------------------+
Adam Smith
smi...@mailbox.syr.edu
Syracuse University
Dept. of Electrical
and Computer Engineering
<Audio Signal Processing>
+---------------------------------------------------------------------------+