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 #3353
Joined: Sat Oct 23 2010, 11:21PM
Location: Greece
Posts: 90
No sockets as far as know, and if you are using the full 100 amps of the MOSFET, it will have to be a very strong socket i think.
PS. I thought you used a different/modified version of the hungarian coil, i hope the info on the original site will be enough if i make that SSTC, thanks!
Registered Member #2292
Joined: Fri Aug 14 2009, 05:33PM
Location: The Wild West AKA Arizona
Posts: 795
You may want to consider using IGBTs. IGBTs don't have a on resistance like MOSFETs do. Rather they operate more like a diode with a fixed voltage drop. when I first built a SSTC I didn't even consider using IGBTs as it seemed that IGBTs were more for pulsed applications were MOSFETs handled a stated state "CW" type duty better.
I have found though that even in SSTCs IGBTs perform very well compared to MOSFETs when price is the driving factor. I know this is not the norm application for IGBTs but this is just my preference when it comes to choosing a switch.
Registered Member #1731
Joined: Thu Oct 02 2008, 02:22PM
Location: Indiana
Posts: 52
Thanks for the replies - I have another batch of MOSFETS coming in today ;)
I think I'll solder in some pins and then attach the MOSFET legs to these so I can install new ones without having to remove the board from the case.
One other thing - the case is direct earth grounded but I can get a small shock from touching it when the coil is running - is this normal? I'm bit concerned as the heatsink is connected to the case - maybe this is part of the problem?
At the moment I don't know if the coil is inducing the charge in the case, or its the result of something else.
Last question - it's been my "intuitive guess" that drawing long arcs out of a topload actually decreases the impedence in the primary circuit allowing more current to flow through the MOSFETS. They nearly always blow when I'm trying to do some goofy arc effect.
Registered Member #1731
Joined: Thu Oct 02 2008, 02:22PM
Location: Indiana
Posts: 52
I found a place on ebay that would sell me 10 of the 260s - they will arrive in a day or two. I'll definitely be trying them out when they get here.
I'm still a bit concerned about the charge on the case/heatsink. Surely this cannot be avoided? The Mosfets heatsink is actually connected to one of the pins (I forget which) so I have been using an electrical insulator when I mount them
usually drain is on tab and middle pin, they are never isolated.
i dont understand how you can get a shock with grounded object, still if you do, i would not simply touch it :) Check grounding, or remove it and put -U on it.
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.
Is there a more robust alternative to IRF3205 MOSFET?
