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 #2909
Joined: Wed Jun 09 2010, 12:31AM
Location: fort belvoir, Va USA ( south of DC)
Posts: 145
i have a bank with the ecact same capacitors, 400v 4700uf, i charche them with two 1:4 500KVA trasformers (each one put out about 460v) put in series then recitifed i get out about 1KV out (i run off of 120V ac) sence i only have 16 of them i have the set for 800v.
Registered Member #90
Joined: Thu Feb 09 2006, 02:44PM
Location: Seattle, Washington
Posts: 301
Tom Williamson wrote ...
Worse yet, if one capacitor is slightly leaky, it will gradually transfer its voltage to the others, possibly exceeding their voltage rating in turn. And if one of them punches through its dielectric barrier, it can then damage others in a cascading fashion. This is why series capacitors are generally avoided in power circuits.
kind of worries me :S
Kinda worries me too, but practically speaking this failure is pretty uncommon. To have some degree of safety, you'd build the capacitors into an enclosure AND check their leak-down rate periodically. How often? Once before each day's firing, just charge it and wait a minute while watching the charge voltage. If it droops unexpectedly fast then go to work with a voltmeter.
During initial construction you'll check how the charge is balanced in all the strings. If two caps in one string are uneven, then find another string that's unbalanced and swap caps to get a better match in capacitance in each series pair.
Our advantage in using series capacitors in coilguns is that their performance is always monitored. My safety blurb on the webpage includes the context of power machinery in a closet that runs for extended periods without attendance.
Cheers, Barry I'm just going to be myself ... primarily because none of the other people in my head want the job.
Registered Member #3324
Joined: Sun Oct 17 2010, 06:57PM
Location:
Posts: 1276
ah ok thanks :) so where should i buy a transformer or how should i wind it?
il do what you said barry but il probibly check it every 3 days instead as that sounds like a long tiresome process, i will put resistors in definately :)
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.
Capacitor Banks
