High voltage/current ignition Long time no see)

Mr.Tallahassee · Mon Mar 05, 2012 12:24 am

I have found an excellent circuit to use as ignition for anything from a standard combustion to a high-pressure hybrid. It uses an ignition coil, an automotive relay, and a capacitor. I wired it to make a Jacob's Ladder and it works quite well. [youtube][/youtube] I found the circuit diagram for it but it was incorrect so I gladly corrected it.

It's been a while since I've been on. I've been a little busy with life to keep up my hobbies.

Zeus · Mon Mar 05, 2012 3:15 am

Good to have you back onboard, it's a reliable circuit, but some will say it's too bulky. Motorbike coils or lawn mower magnetos work well, and are smaller.

Just don't touch the output, very rough.

Technician1002 · Mon Mar 05, 2012 3:34 am

If you can't find an automotive type cap, a sweep mylar or polyester cap from an old CRT monitor will do the job. Find a value between 0.1uF and 0.47 uF rated at least 200 Volts. Don't use an electrolytic in a can. This cap is a dipped cap often orange in color.

Most ignition condensors are in the 0.24 to 0.35 uF range.

Mr.Tallahassee · Mon Mar 05, 2012 4:21 pm

I used capacitors from TV's and CRT Monitors. They are all rated to at least 1.2kv. I checked each one and ended up tossing dozens aside for later use. I plan on trying out a few different, smaller setups. Such as using a "tazer" made from an audio transformer added to a HV rated multiplier. This was more intended for larger builds. This could be used in something like this.

[youtube][/youtube]

except most likely metered.

jimmy101 · Mon Mar 05, 2012 7:42 pm

Aka a "buzz coil" driving an ignition coil. Similar to the Model T ignition system (linky), and traditional points based automotive ignition systems, as well as early radio transmitters.

Mr.Tallahassee · Mon Mar 05, 2012 8:12 pm

It really is an amazingly simple device. It works every time. It's also fun to tinker with as a HV power supply. I was actually playing with a relay I had while wondering what I could do. Crossed random wires and it buzzed which, at first, scared the holy crap out of me. I opened it up to find out why it buzzed and then I youtube'd the idea. Seems very common. Only issue is how fast it sucks through relays if you aren't careful too let them cool. Any ideas on high voltage toys using about 50kv AC?

natas · Tue Mar 06, 2012 3:08 am

this is a similar and maybe less bulky way to make a jacob ? [youtube][/youtube]

Hotwired · Tue Mar 06, 2012 7:32 am

I've actually made a jacobs ladder with my totally-not-a-stun-gun with literally two wires off the output but it's terribly unreliable when in front of a camera.

Could be a contestant for smallest jacobs ladder ever since the ones I can find on a casual search are, yes small ladders but with something huge powering it.

Mr.Tallahassee · Tue Mar 06, 2012 5:43 pm

Well, I got hit with an ungrounded arc off of the ladder. Ouch! I immediately checked my pulse. Thankfully it was ungrounded. If I had been holding the power supply wire then that would be it for me.

It definitely packs a punch. I actually have a few circuits for HV supplies. Some are around 1000-2000 volts while others are +100kv. I'll dig through and find some for ideas and post them here. (HV thread anyone?

)

Zeus · Tue Mar 06, 2012 6:17 pm

Having had arm to arm contact with that circuit, with a high power ignition coil, and getting the "death grip" on the terminals. I can tell you, it's not lethal. Very painful though. Won't mention the tunnelling burns.

Can I point you towards 4hv.org. the people there are helpful, there's lots of good projects, boards for electromagnetic launchers (Wyz, you might like this), and a lot of other good stuff.

natas · Tue Mar 06, 2012 6:48 pm

A 100k volt stun gun, is a really weak stungun... its jus a little kick.. its not before 500k ones u get hurt

900k.. and u go down hard.. (at least i did )
its ampheres that kills you...

Mr.Tallahassee · Tue Mar 06, 2012 7:44 pm

Ive had 100k put me on my back. My friend sitting next to me freaked as I went stiff on the deck. I twitched for a good ten seconds. Of course, it's not lethal unless it crosses the heart with a good 100 milliamps or so(I think). As hot as that spark is, I'm certain it's producing decent current. Maybe not truly lethal but enough to get your attention for sure. Got mine!

I couldn't imagine how painful a 900k feels.

Hotwired · Wed Mar 07, 2012 9:24 am

Come on, don't promote BS from the companies that make stunguns.

100,000V

500,000V

900,000V

You REALLY think a stun gun with a spark gap of an inch or less has a voltage difference like that?

Call it about 30,000V per centimetre that a spark can jump in air as a very rough guide.

Remember if the gap is less than that it will spark at a much lower voltage.

So for a spark at 900,000V to exist at all you need a gap of 30cm or the length of a 12" ruler.

If the gap is not 12" across then as the voltage rises it will jump across at the lowest voltage it needs to bridge the gap.