What is the easiest way to create electric arc?

Hello,
It is my first post on these forums, I hope it is proper section.

What is the easiest way to create electric arc? (with simple electronical elements) It doesn't have to be huge, 1cm would be enough.

Also, can I somehow calculate how big arc will be based on voltage?

I have made small Joule theft circuit, which was able to power LED from single AAA battery, but even when I was increasing input voltage, I couldn't create any arcs with it.

Does it matter if it is DC or AC voltage? Would both create arcs?

I have old 230V AC to 9V AC transformer lying around. Can I use it other way around, creating 230V from 9V?

Re: Creating electric arcs.

An oscillator with an autotransformer to step up to a few kV with 2000:1 ratio or more.

THen drives a chain of voltage doublers (diode caps) then a ladder of RC filters.

Video

THis example shows such a device . As the voltage builds up every few seconds , it zapps. Must really drain the single AAA cell.
Here they use 1Mohm rated for only 500V but operating at a few kV with arc zener gap over each R, and small Tantalum caps which usually only have a max rating of 125V.. and possibly conditioned to run at higher. hmm.

Re: Creating electric arcs.

You can get also big arc on low voltage, this is not problem, even with just one part.

:wink:

Re: Creating electric arcs.

You need about 1kV/mm to breakdown the air dielectric, in this demo about 1" or 25kV to initiate the arc.

Once this starts each smaller arc suppression bypasses each resistor in rapid succession shorting out each resistor and delivery a charged voltage from each low voltage cap in parallel with the follow on current.

You can generate a spark with one battery on shorting it, but in this case it charges up the caps to 1kV or more and then when the secondary inductance reaches enough voltage to arc the big gap, the smaller gaps act as switches to merge the low voltage caps in parallel to delivery the high current.

I once worked with a very good design engineer who used a gas tube to suppress arcs on a low voltage 48Vac line for outside repeaters. A non-direct hit from a lightning storm triggered the gas tube and the high Amp surge from the power line, burnt all the copper tracks in its path and a hole in the epoxy board. He would not believe me that it was a design fault, so I demonstrated how the gas tube is a negative resistance device and simulated it with a 1Mohm and a 10uF cap charged at 10V and a car autotransformer that with a low voltage primary pulse. A 1kV spark arc shorted out the gas tube which drained the 10V charge on the cap and made the gas tube glow. THis current could not pass thru the resistor. So he changed the design to put in current limiting.. THe gas tube in his case was acting as an SCR (which is also a negative resistance device) and the follow-on current melted the tracks.

Yes one auto ignition coil on secondary to 1.5V cell will generate a big spark. V=L di/dt (di/dt is limited by winding capacitance and frequency response of coil around 20KHz for a big coil.)

Re: Creating electric arcs.

Big arc even several cm in length only with stronger transformer like for SMAW/REL welding (Arc Welding). Voltage can be 24V and in that case higher current is needed. Shape of that arc is different from this high voltage. Of course in your way this is not possible because you have weak transformer for that, but this can get with two-three-four car lead acid batteries in serie.

Of course this is complete different from your project but is possible.

:wink:

Re: Creating electric arcs.

A pulse transformer does not have the lossy iron core designed for 50/60Hz. These tend to be air core or minimal iron power core and would work better.

just take to 9 volts battery with their op poles connected together directly then slightly move one of the pole there will be a small spark of about a mm long

i am curious to know why you are planning to set an electric arc up


remember higher the voltage the current tends to take the least resistive that can also be your body which offers a mega ohm of resistance to current if you are all wet the arc may be set up near you in the case of 1 kV / mm watch really high power and if it is dc it may put an end to you

Re: Creating electric arcs.

Isn't marx generator dangerous by producing x-rays? I have also read that these Jacobs Ladders ionize air, creatic ozone, which can be deadly.

tpetar said:

You can get also big arc on low voltage, this is not problem, even with just one part.

:wink:

Click to expand...

Can you be more specific with, please?

tpetar said:

Big arc even several cm in length only with stronger transformer like for SMAW/REL welding (Arc Welding). Voltage can be 24V and in that case higher current is needed. Shape of that arc is different from this high voltage. Of course in your way this is not possible because you have weak transformer for that, but this can get with two-three-four car lead acid batteries in serie.

Of course this is complete different from your project but is possible.

:wink:

Click to expand...

So I have to either increase current or voltage? What voltage and current amount is deadly? Won't thick wires burn or heat too much? How can I determine what kind of wire do I need for different voltages/current?

jeffrey samuel said:

just take to 9 volts battery with their op poles connected together directly then slightly move one of the pole there will be a small spark of about a mm long

remember higher the voltage the current tends to take the least resistive that can also be your body which offers a mega ohm of resistance to current if you are all wet the arc may be set up near you in the case of 1 kV / mm watch really high power and if it is dc it may put an end to you

Click to expand...

I was actually wondering what is going on, because with single 9V battery I don't have any sparks, I have ever tried connecting few 9V batteries or putting them into Joule Theft. On the other hand, with 5V power from my USB, micro sparks do show.

i am curious to know why you are planning to set an electric arc up

Click to expand...

Fascination, taking the opportunity that I have recently started learning electronics and microcontrollers.

Jacobs Ladder or Tesla coil would make me happy, but I wanted to start small.

I have found some ideas here, but I can't really understand what he is doing and those schematics don't help me much:
https://www.pocketmagic.net/?p=802

Will any 22nF capacitors work?
Does ferrite core mean any metal that I can stick magnes to?
Those 250 turns should be done first and then on top of that 2 15 turns?
It have to be 5-12V any amperage?
Can I use any wire?

The simplest I've ever done, is a car ignition coil, a relay and a resistor.
The coil primary is from 12V to relay NC, relay COM to resistor to Gnd.
Relay coil across the resistor. When coil current times R exceeds coil
pull-in voltage, the current is interrupted and you get the flyback spark.
A snubber network across the contacts (ignition condenser) would
improve things, but I didn't bother.

Playing with this knocked me right out, once. Check yourself.

the point is micro sparks are not visualised so easily that is the prob

if the length of the spark has to be more than a few cms higher voltage and thereby either high current or voltages are involved better be careful with this

your facination is ultra cool but the risk involved is not the worth if for mere fun try to improvise some thing more using the sparks

Is this simple enough?

**broken link removed**
Substitute a surplus 6V or 9V or 12V relay or even a reed relay for bigger arcs

since V = L * delta I / delta t ,

You can control voltage with more inductance, L more current being switched off in primary (delta I) in coil and less and faster off time (delta t) , the product of all these numbers gives rise to voltage The "autotransformer" (aka ignition coil) then steps it up another 100x.

Stray capacitance across the switch in the order of pF and capacitance in the windings prevents this time from being 0, at which point voltage would be infinite in theory.

Motorcycle ignition coil< I am sure you can find an auto recycling yard with parts.

https://www.penguinslab.com/ignitioncoil.htm


It is possible to use a dual contact relay to disable the coil voltage when activated so connecting coil from battery to NC or normally closed contact to coil will activate coil and release it immediately, effectively making it oscillate as fast as it can without any driver or transistor. Depending on ratings a relay has 1million cycle life and 100K cycle if you stay within all contact specs. In this case the arc on the contacts creates pitting so cars use a Capacitor to extend the life of the contacts and also reduce the arc bandwidth for interference reasons ( old mechanical distributor contact points are similar to relay contacts).

If you understand the size of a 1/4 wave length antenna vs frequency TV antenna elements get shorter as channel goes up, and you know the size of dipole for WIFI at 2.4GHz and gap of spark plugs implies an even higher frequency. The size of the actual plasma arc , as it gets smaller limits the maximum frequency of the emissions, if the arc ionizes a shorter wavelength of air within the gap then this can extend the signal bandwidth up to X-Rays but spreads out each spike at the repetition rate to lower levels so it wont be high power XRay.

Arc welders have similar exposure to emissions but at much higher currents, I am not sure what they do for safety but the rise time of the arc is one thing, not to worry about health radiation exposure except conducted shocks but the radiated emissions of the cables of high RF current for extended periods of time will show up as bloodshot eyes within a day of testing up close.

I suspect Tesla died of radiation poisoning effects from prolonged exposure to high power emissions.. The sensitivity to RF on humans is well researched by the US Military and is in the public domain which I have read 40yrs ago in MIL-HDBK's in our company library.

is there then potentially lethal effects from over exposure to electric arc

jeffrey samuel said:

is there then potentially lethal effects from over exposure to electric arc

Click to expand...

No, my friend, bigger danger and lethal result have some fresh fruit from market full of pesticide. But certainly not healthy to expose body cells to ionized environment for longer period. Human bodz is very strong and its inert for many things, lots of consequences showsup later in older period of life.

tpetar said:

No, my friend, bigger danger and lethal result have some fresh fruit from market full of pesticide. But certainly not healthy to expose body cells to ionized environment for longer period. Human bodz is very strong and its inert for many things, lots of consequences showsup later in older period of life.

Click to expand...

instantaneous impact is negligible but prolonged high level exposure shows its true colour in the later part of our life correct

awesome one t petar

Yes, and there should be added that we dont know all reasons of all disease, such as cancer for example, we know only some small part and we think that we know lots.

Nikola Tesla died 7.1.1943. in 86 age of life, this is long life even for todays life ranges. There is some speculations this days that Nikola Tesla was Murdered by Otto Skorzeny. All is possible who knows. Here is one article about this **broken link removed**

let us leave those to the medicos my man never to be troubled by the horrid memoirs of the causative agents of such and such diseases

Yes my friend I agree with You completely.