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In a chemistry project I want to pursue, I need to temporarily ionize air, which I aim to achieve with a continuous electrical arc jumping across two wires. I am a true novice when it comes to electrical engineering, but I know for an arc to travel across the air one inch, it requires 1000 volts. A simple piezo igniter can do this momentarily, but how do you increase the voltage of a battery so it can do this same thing over a long period of time?

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  • \$\begingroup\$ The needed voltage is 3000V per millimeter. For an inch, that'd be over 76000V. \$\endgroup\$ – JRE Oct 27 '16 at 19:18
  • \$\begingroup\$ Check this out. \$\endgroup\$ – EM Fields Oct 27 '16 at 19:21
  • \$\begingroup\$ It is not hard to find air ionizer projects. Do note that ozone is rather bad for your lungs (like chlorine gas is bad), so you'll want to find some way of keeping the ozone away from you. \$\endgroup\$ – Andrew Morton Oct 27 '16 at 19:38
  • \$\begingroup\$ Jacob's ladder circuit, perhaps? \$\endgroup\$ – pjc50 Oct 27 '16 at 20:05
  • \$\begingroup\$ You don't need an arc to ionize air, you can do it with a corona. What is it you're trying to achieve with your project? \$\endgroup\$ – EM Fields Oct 27 '16 at 20:42
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A module like this might be of use. They can step up the voltage from 3v (two AA batteries) to a high voltage that can create small arcs that will ionize the air. Just search ebay for "high voltage converter".

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  • \$\begingroup\$ One could also use backlight inverters as used for the CCFL screens of older TFTs and notebook computers. The advantage is the high voltage is also high frequency, which makes it somewhat safer to handle (no way muscles/heart can shudder with it, so touching it will be painful because of local burning but not lethal.) \$\endgroup\$ – Janka Oct 28 '16 at 0:51
  • \$\begingroup\$ Besides being dishonest (not 400 kilovolts!) those modules are DC output. Their sparks are nothing like a silent corona or flame-arc. More like a repeated camera flash. \$\endgroup\$ – wbeaty Jan 26 '17 at 5:39
  • \$\begingroup\$ infact they are very much like a stun gun \$\endgroup\$ – Jasen Aug 27 '17 at 22:39
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All you need is to make an electro-mechanical buzzer, like this one, and add a secondary winding over the top of primary coil. You might need to experiment with quality of isolation, to avoid self breakdown in the secondary coil, something like sectional winding. And make sure you don't kill yourself by using too strong batteries.

And the typical breakdown voltage under usual humidity conditions (30-40%) of the air is about 10kV/cm.

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  • \$\begingroup\$ Can I just connect this with a 1.5V aa battery? \$\endgroup\$ – Ryan Oct 27 '16 at 21:14
  • \$\begingroup\$ @Ryan - No. Simply no. 1.5 volts will not support a visible arc unless you provide extremely high current, like an arc welder does. And if you do that, you need an active system to keep the electrodes at just the right spacing as the arc erodes one and builds up the other. \$\endgroup\$ – WhatRoughBeast Oct 27 '16 at 21:18
  • \$\begingroup\$ Yes you can, but the linked buzzer is a 24V device. To use a 1.5V battery you will need to re-wind the primary coil with quite thicker magnet wire. And your secondary coil will need to have a bigger winding ratio to get into 10-kV output range. But the AA battery will give you a safer device. \$\endgroup\$ – Ale..chenski Oct 27 '16 at 21:55
  • \$\begingroup\$ Would this be an adequate substitute? amazon.com/dp/B00T2PNW2W/ref=cm_sw_r_cp_api_gPNeyb8388SRS \$\endgroup\$ – Ryan Oct 27 '16 at 22:07
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    \$\begingroup\$ 700kV from a cheap, handheld device is a ridiculous claim. When you go anywhere beyond 5000V, insulation becomes crucial and this places a lower limit on the size of the arrangement, and/or the materials used. \$\endgroup\$ – Janka Oct 28 '16 at 0:57
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You should use TDI or CDI circuit, similar to that or car ignition.

https://4.bp.blogspot.com/-SKfGYEftTbE/Vya06GTKj6I/AAAAAAAANoY/9nFrUCcqhQIMoy6I723UkR2iNIGMnM07wCLcB/s1600/enhanced%2Belectronic%2BCDI%2Bcircuit.png

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