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 #190
Joined: Fri Feb 17 2006, 12:00AM
Location:
Posts: 1567
One of my relative had some "junk" he got at a garage sale and brought it over, knowing I might find something interesting. Here are the pictures:
I recognized this as a microwave transformer, even though I never had one, other than inside my working microwave oven. I measured the output voltage at 1.3kv from the thick red wire to the casing. When I put a current meter on the output and slowly raised the input power, the input current was over 13A when the input voltage was about 80v. I didn't feel like moving to one of my 20A outlets to measure the full shorted current.
I know that MW transformers are not current limited. So, if I were to short the ends to draw an arc, how much current would this draw? Are we looking at 20-25A? I probably would never use one of these, but am I correct to say that to safely use this I would need an inductor in series, like another MW transformer primary, to act as a ballast? Does anyone recognize the model I have shown in the pictures?
Registered Member #152
Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384
Well, the 230VAC transformers draw 20-25A shorted (thats up to 6kVA!) For some reason, the 120V ones seem to pull less VA, so I'd guess it would take ~30A with full input and shorted output.
The 1.3kV is really weird, as most MOTs are designed at 2100VAC output.
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Dr. Kilovolt wrote ...
IamSmooth wrote ...
I was only putting in 115vac. Where you assuming I was using 230vac?
Also, what is a typical capacitance for the capacitor for a MOT?
The capacitors I've seen were from 0.8 to 1 uF.
That is what it usually is, but i have one that is .6uf. The weird thing was it was a bigger mot that it was with.. I don't know the reason, but i also have one that is like .7uf.
Registered Member #190
Joined: Fri Feb 17 2006, 12:00AM
Location:
Posts: 1567
Yes. I've been away from the board for a while. Busy at work.
What did I do to make you say I'm cautious, not that I mind?
Working in the hospital I've seen a lot of bad injuries from stupid mistakes. I've also had my share of stupid mistakes in my past. I want to keep my limbs, eyes and nervous system intact.
WIth regard to the capacitor, I found one 0.95uf/2000vac in the junk box.
Registered Member #95
Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308
Oh nothing really. It's just that I've never seen any of the standard flyback, MOT or TC projects from you ever before. Yet I have no doubt that you know enough to put some of these projects together, as you ask a lot of theory questions. And that you haven't tried arcing with your MOT yet.
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.
I just got a microwave transformer
