If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #1643
Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039
Not to forget that you can run ignition coil to build jacob ladders off a 9V battery also...You don't NEED 120V, If you make a driver, you just need 12V :D
Problem for that guy was, He had no 2N3055, and he didn't have the 2 10K pots to tune it to the right frequency to get large spark arches..But many are by 12V and still make 1-3 inch arches
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Yes, you can drive an ignition coil with a 9 volt battery, but i guarantee you will not be able to get a jacobs ladder to work with it.
If you do make an ignition coil driver, i would suggest a 10ohm resistor in series with a 10 nanofarad capacitor to catch any high voltage spikes. I know this is not a great way of doing it, but it made my 555's and mosfets/transistors last much longer. However, you do want the primary voltage to rise as high as possible.
When the primary receives a pulse, the core becomes magnetizes. When that pulse stops the field collapses, which induces a high voltage into the secondary, and primary aswell. If you have an ignition coil that steps voltage up say 100x, the voltage that is induced on the primary will be multiplied 100 times. So if you had a 100 volt spike on the primary, you would get 10,000 volts out. That means the mosfet would have to withstand more than 100 volts.
So, using a 'snubber' as stated above, will reduce the kickback on the primary which will reduce secondary voltage.
Registered Member #540
Joined: Mon Feb 19 2007, 07:49PM
Location: MIT
Posts: 969
It would have to be rated a lot more than 100V. The primary will try to keep the current flowing. The faster you switch the iggy coil, the more voltage your MOSFET will have to be able to withstand since the MOSFET is the only thing that is preventing the current from flowing.
Registered Member #152
Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384
You can use a capacitor across the primary like it's used in TV's. I have used this setup with TV transformers and it works great. The idea is that the cap slows down the pulse so peak voltage gets greatly reduced (the same area under the V curve). Another benefit is that the voltage rises slower, allowing the switching device to turn off more "softly" thus decreasing switching losses pretty dramatically.
Registered Member #1643
Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039
I'll prob. end up using a 12V power source like a lot of people on youtube do with ignition coils and Jacob ladders. I they arnt car batterys, they're smaller..
Registered Member #834
Joined: Tue Jun 12 2007, 10:57PM
Location: Brazil
Posts: 644
50 kV from an ignition coil is too much. The insulation around the HV terminal is enough for, maybe, 30 kV. In normal operation no more than 15 kV are produced. For more than this, the whole system must be immersed in oil, supposing that the internal insulation doesn't fail. The "record" so far was obtained with a coil with the core removed, immersed in oil and operated as a Tesla coil.
Registered Member #1132
Joined: Mon Nov 19 2007, 06:15PM
Location: Slovenia
Posts: 84
Yes the terminal arcs over pretty soon,What i did was stuck some garden hose over the terminal and used tons of varnish on it.That kept it from arcing over its terminal but in the end arced over internally and bye bye coil.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
What type of fun do ignition coils have?
