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 #38645
Joined: Thu Oct 17 2013, 01:36PM
Location:
Posts: 1
I am working on a project to build an air gap flash for high speed photography and need to better understand how to charge a high voltage capacitor.
I am following this schematic:
Which is from this build:
I like this build because it uses a compact 25kV power supply that is relatively inexpensive to buy.
I have purchased all of the parts for the project except for the high voltage power supply.
For my capacitor I was able to obtain a Maxwell capacitor rated at 50kV, .04uF, and .017uH internal inductance.
My question is regarding how the current needs to be limited while the capacitor charges. In the schematic it looks like the cap is hooked up to the power supply without a current limiting resistor. I'm guessing this works because the power supply he is using can be using in either current control or voltage control mode. Here is a link to the power supply website it is part number HV250(+):
The power supply vendor indicates that if the power supply is run in current control mode that you won't need a current limiting resistor, but that the final voltage of the capacitor might be higher than the power supply's rated output because the power supply voltage will tend to 'soar' over the rated voltage. How can I determine how much overhead my capacitor will need in its voltage rating to accommodate the 'soaring voltage'?
Any insights would be appreciated. I have worked on many low voltage, digital electronics projects in the past, but never anything with this high of voltage and figured I should get familiar with what I am doing before attempting anything.
Registered Member #2901
Joined: Thu Jun 03 2010, 01:25PM
Location:
Posts: 837
Couldn't you put a massive stack of TVS diodes on the output to limit voltage? (About 10 Euro worth of P6KE440A_Q at mouster, if you buy them before they run out.) Put a LED in the string to know when the desired output voltage is reached.
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.
Charging capacitor for air gap flash
