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 #4082
Joined: Wed Aug 31 2011, 07:57PM
Location: wolverine lake MI
Posts: 5
hello everyone, logistical question with regards to building my first coil. where exactly does one buy 150' of 1/4 " copper tubing. of course, just due to metal value it will be expensive, but i cant seem to find it online anywhere for ANY price. so where can i buy such a thing, or if i cannot, what are acceptable methods of joining shorter lengths of tubing to produce one?
Registered Member #480
Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644
atemporal -
Something must have jumped the tracks here ...... whatever would you need 150 feet (did I read that right??) of 1/4" copper tubing for?
Do you have your coil completely designed (using TC design software like JAVATC or WINTESLA) so you know exactly how much primary inductance you need, and therefore how much copper tubing you need for your primary?
A correctly-designed small-to-midsize spark gap TC will require no more than 50' of 1/4" tubing for the primary.
Please post your entire set of design parameters here for review (the JAVATC or WINTESLA data file).
Registered Member #4082
Joined: Wed Aug 31 2011, 07:57PM
Location: wolverine lake MI
Posts: 5
i was attempting to design from scratch, but upon using javatc, i came up with about 75' of tubing, which can be obtained. guess i just needed to swallow my pride and bow to superior knowledge.
Registered Member #480
Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644
atemporal -
There is no "designing from scratch". To obtain resonance, the inductance and capacitance values of both primary and secondary circuits MUST be determined and then achieved in your construction.
75' of primary tubing is still way off base. Please post your JAVATC file so we can understand what you are trying to build, and the forum will critique your design before you go off on a painful tangent.
Make sure you fully understand Tesla coil theory of operation and standard construction practices before you start blindly buying component parts. Still the world's best single source of technical information on TC design and operation is Richie Burnett's site at:
At an absolute minimum you need to understand primary/secondary resonance, quenching, resonant rise, coupling, spark gap operation and "tuning" before you try to finalize a "design".
Registered Member #4082
Joined: Wed Aug 31 2011, 07:57PM
Location: wolverine lake MI
Posts: 5
by "designing from scratch" i meant running the necessary numbers and calculations independantly, and not in any combined calculator. i understand lc resonance, power factor correction, spark gap operation, capacitor spec, ect. i just wasn't able to optmize the dimensions of the primary coil, and thats where a little digital help came in. JAVATC did little to change any other specs in my design which strongly suggests i wasnt too off base.
heres the readout from JAVATC just to back this up:
J A V A T C version 12.5 - CONSOLIDATED OUTPUT Wed Aug 31 17:12:04 2011
-----------------------------------------
----------- Secondary Outputs: -----------------------------------------
----------- 140.02 kHz = Secondary Resonant Frequency 90 deg° = Angle of Secondary 33 inch = Length of Winding 33.9 inch = Turns Per Unit 0.00412 inch = Space Between Turns (edge to edge) 1759.3 ft = Length of Wire 5.5:1 = H/D Aspect Ratio 28.1686 Ohms = DC Resistance 28842 Ohms = Reactance at Resonance 3.42 lbs = Weight of Wire 32.783 mH = Les-Effective Series Inductance 33.169 mH = Lee-Equivalent Energy Inductance 32.022 mH = Ldc-Low Frequency Inductance 39.41 pF = Ces-Effective Shunt Capacitance 38.952 pF = Cee-Equivalent Energy Capacitance 52.961 pF = Cdc-Low Frequency Capacitance 7.96 mils = Skin Depth 34.294 pF = Topload Effective Capacitance 92.0132 Ohms = Effective AC Resistance 313 = Q
-----------------------------------------------
----- Primary Outputs: -----------------------------------------
----------- 140.03 kHz = Primary Resonant Frequency 0.01 % = Percent Detuned 0 deg° = Angle of Primary 73.54 ft = Length of Wire 13.24 mOhms = DC Resistance 0.305 inch = Average spacing between turns (edge to edge) 2.617 inch = Proximity between coils 0 inch = Recommended minimum proximity between coils 115.678 µH = Ldc-Low Frequency Inductance 0.01119 µF = Cap size needed with Primary L (reference) 0.058 µH = Lead Length Inductance 160.119 µH = Lm-Mutual Inductance 0.083 k = Coupling Coefficient 0.135 k = Recommended Coupling Coefficient 12.05 = Number of half cycles for energy transfer at K 42.83 µs = Time for total energy transfer (ideal quench time)
-------------------------------------------
--------- Transformer Inputs: ------------------------------------------
---------- 110 [volts] = Transformer Rated Input Voltage 15000 [volts] = Transformer Rated Output Voltage 60 [mA] = Transformer Rated Output Current 60 [Hz] = Mains Frequency 110 [volts] = Transformer Applied Voltage 0 [amps] = Transformer Ballast Current 0 [ohms] = Measured Primary Resistance 0 [ohms] = Measured Secondary Resistance
--------------------------------------
-------------- Transformer Outputs: -----------------------------------------
----------- 900 [volt*amps] = Rated Transformer VA 250000 [ohms] = Transformer Impedence 15000 [rms volts] = Effective Output Voltage 8.18 [rms amps] = Effective Transformer Primary Current 0.06 [rms amps] = Effective Transformer Secondary Current 900 [volt*amps] = Effective Input VA 0.0106 [uF] = Resonant Cap Size 0.0159 [uF] = Static gap LTR Cap Size 0.0277 [uF] = SRSG LTR Cap Size 197 [uF] = Power Factor Cap Size 21213 [peak volts] = Voltage Across Cap 53033 [peak volts] = Recommended Cap Voltage Rating 2.52 [joules] = Primary Cap Energy 209.1 [peak amps] = Primary Instantaneous Current 43.4 [inch] = Spark Length (JF equation using Resonance Research Corp. factors) 12.4 [peak amps] = Sec Base Current
-----------------------------------------
----------- Rotary Spark Gap Inputs: ------------------------------------------
---------- 0 = Number of Stationary Gaps 0 = Number of Rotating Electrodes 0 [rpm] = Disc RPM 0 = Rotating Electrode Diameter 0 = Stationary Electrode Diameter 0 = Rotating Path Diameter
----------------------------------------
------------ Rotary Spark Gap Outputs: -----------------------------------------
----------- 0 = Presentations Per Revolution 0 [BPS] = Breaks Per Second 0 [mph] = Rotational Speed 0 [ms] = RSG Firing Rate 0 [ms] = Time for Capacitor to Fully Charge 0 = Time Constant at Gap Conduction 0 [µs] = Electrode Mechanical Dwell Time 0 [%] = Percent Cp Charged When Gap Fires 0 [peak volts] = Effective Cap Voltage 0 [joules] = Effective Cap Energy 0 [peak volts] = Terminal Voltage 0 [power] = Energy Across Gap 0 [inch] = RSG Spark Length (using energy equation)
---------------------------------------
------------- Static Spark Gap Inputs: ------------------------------------------
---------- 8 = Number of Electrodes 0.125 [inch] = Electrode Diameter 0.524 [inch] = Total Gap Spacing
-----------------------------------------
----------- Static Spark Gap Outputs: -----------------------------------------
----------- 0.075 [inch] = Gap Spacing Between Each Electrode 21213 [peak volts] = Charging Voltage 21203 [peak volts] = Arc Voltage 31862 [volts] = Voltage Gradient at Electrode 40465 [volts/inch] = Arc Voltage per unit 100 [%] = Percent Cp Charged When Gap Fires 5.654 [ms] = Time To Arc Voltage 177 [BPS] = Breaks Per Second 2.52 [joules] = Effective Cap Energy 359542 [peak volts] = Terminal Voltage 445 [power] = Energy Across Gap 47.8 [inch] = Static Gap Spark Length (using energy equation)
Registered Member #480
Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644
atemporal -
OK, you're on the right track now. When you start out asking about a 150' primary conductor for a small/medium coil, it gives the initial impression that something is amiss.
Use JAVATC to run alternate scenarios. Your 6" X 36" toroidal topload is a little disproportionate for a 6" diameter secondary, so try reducing that to something like 6" X 24" or 6" X 30" and see what happens to your primary conductor length. Then, try increasing your tank cap value to .018 or .02uF. Your coupling coefficient could be increased slightly, or better yet design the mechanics of the system so you can adjust the relative height of the primary/secondary to allow adjustment of K. Do you have adequate spacing between the OD of the secondary and the ID of the primary? You'll probably want at least 1" with a 15KV power supply.
Registered Member #4082
Joined: Wed Aug 31 2011, 07:57PM
Location: wolverine lake MI
Posts: 5
OK changed toroid to 24", and MMC value to 0.02 uF, and get a much more reasonable value of 40' of wire needed. my question is, how much voltage overhead should my MMC really need? to provide the necessary capacitance using the best caps i could find (cornell dubilier 942C20P15K-F) to get the recommended ratings for voltage (53KV) and capacitance (0.02uF), i would need quite a few capacitors, and that would also be quite expensive. is there also some way to optimize the MMC to use less caps, or are there larger, better high-voltage caps i just haven't found yet? getting slightly off topic, but any help would be appreciated.
heres the new JAVATC log:
J A V A T C version 12.5 - CONSOLIDATED OUTPUT Wed Aug 31 22:56:09 2011
-----------------------------------------
----------- Secondary Outputs: -----------------------------------------
----------- 168.19 kHz = Secondary Resonant Frequency 90 deg° = Angle of Secondary 33 inch = Length of Winding 33.9 inch = Turns Per Unit 0.00412 inch = Space Between Turns (edge to edge) 1759.3 ft = Length of Wire 5.5:1 = H/D Aspect Ratio 28.1686 Ohms = DC Resistance 33698 Ohms = Reactance at Resonance 3.42 lbs = Weight of Wire 31.888 mH = Les-Effective Series Inductance 33.056 mH = Lee-Equivalent Energy Inductance 32.022 mH = Ldc-Low Frequency Inductance 28.081 pF = Ces-Effective Shunt Capacitance 27.089 pF = Cee-Equivalent Energy Capacitance 41.849 pF = Cdc-Low Frequency Capacitance 7.27 mils = Skin Depth 22.764 pF = Topload Effective Capacitance 101.075 Ohms = Effective AC Resistance 333 = Q
-----------------------------------------------
----- Primary Outputs: -----------------------------------------
----------- 168.19 kHz = Primary Resonant Frequency 0 % = Percent Detuned 0 deg° = Angle of Primary 41.8 ft = Length of Wire 6.94 mOhms = DC Resistance 0.438 inch = Average spacing between turns (edge to edge) 3.025 inch = Proximity between coils 0 inch = Recommended minimum proximity between coils 44.801 µH = Ldc-Low Frequency Inductance 0.02001 µF = Cap size needed with Primary L (reference) 0.138 µH = Lead Length Inductance 91.43 µH = Lm-Mutual Inductance 0.076 k = Coupling Coefficient 0.135 k = Recommended Coupling Coefficient 13.16 = Number of half cycles for energy transfer at K 38.97 µs = Time for total energy transfer (ideal quench time)
-------------------------------------------
--------- Transformer Inputs: ------------------------------------------
---------- 110 [volts] = Transformer Rated Input Voltage 15000 [volts] = Transformer Rated Output Voltage 60 [mA] = Transformer Rated Output Current 60 [Hz] = Mains Frequency 110 [volts] = Transformer Applied Voltage 0 [amps] = Transformer Ballast Current 0 [ohms] = Measured Primary Resistance 0 [ohms] = Measured Secondary Resistance
--------------------------------------
-------------- Transformer Outputs: -----------------------------------------
----------- 900 [volt*amps] = Rated Transformer VA 250000 [ohms] = Transformer Impedence 15000 [rms volts] = Effective Output Voltage 8.18 [rms amps] = Effective Transformer Primary Current 0.06 [rms amps] = Effective Transformer Secondary Current 900 [volt*amps] = Effective Input VA 0.0106 [uF] = Resonant Cap Size 0.0159 [uF] = Static gap LTR Cap Size 0.0277 [uF] = SRSG LTR Cap Size 197 [uF] = Power Factor Cap Size 21213 [peak volts] = Voltage Across Cap 53033 [peak volts] = Recommended Cap Voltage Rating 4.5 [joules] = Primary Cap Energy 449 [peak amps] = Primary Instantaneous Current 43.4 [inch] = Spark Length (JF equation using Resonance Research Corp. factors) 16.8 [peak amps] = Sec Base Current
-----------------------------------------
----------- Rotary Spark Gap Inputs: ------------------------------------------
---------- 0 = Number of Stationary Gaps 0 = Number of Rotating Electrodes 0 [rpm] = Disc RPM 0 = Rotating Electrode Diameter 0 = Stationary Electrode Diameter 0 = Rotating Path Diameter
----------------------------------------
------------ Rotary Spark Gap Outputs: -----------------------------------------
----------- 0 = Presentations Per Revolution 0 [BPS] = Breaks Per Second 0 [mph] = Rotational Speed 0 [ms] = RSG Firing Rate 0 [ms] = Time for Capacitor to Fully Charge 0 = Time Constant at Gap Conduction 0 [µs] = Electrode Mechanical Dwell Time 0 [%] = Percent Cp Charged When Gap Fires 0 [peak volts] = Effective Cap Voltage 0 [joules] = Effective Cap Energy 0 [peak volts] = Terminal Voltage 0 [power] = Energy Across Gap 0 [inch] = RSG Spark Length (using energy equation)
---------------------------------------
------------- Static Spark Gap Inputs: ------------------------------------------
---------- 8 = Number of Electrodes 0.125 [inch] = Electrode Diameter 0.524 [inch] = Total Gap Spacing
-----------------------------------------
----------- Static Spark Gap Outputs: -----------------------------------------
----------- 0.075 [inch] = Gap Spacing Between Each Electrode 21213 [peak volts] = Charging Voltage 21203 [peak volts] = Arc Voltage 31862 [volts] = Voltage Gradient at Electrode 40465 [volts/inch] = Arc Voltage per unit 100 [%] = Percent Cp Charged When Gap Fires 18.437 [ms] = Time To Arc Voltage 54 [BPS] = Breaks Per Second 4.5 [joules] = Effective Cap Energy 576135 [peak volts] = Terminal Voltage 244 [power] = Energy Across Gap 43.2 [inch] = Static Gap Spark Length (using energy equation)
Registered Member #480
Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644
atemporal -
For a fairly reliable MMC assembled from the C-D 942C20P15K, you'll need around 40 caps - 2 parallel strings of 20 each. These caps are very reliable in TC service when the MMC is conservatively designed for both peak voltage and peak current. Alternatives are capacitors with low-loss dielectrics specifically designed for high-current, high frequency service. New, these are much more expensive than an MMC. Surplus caps from medical or industrial laser systems, ex-military radar systems, RF induction heating systems, etc. can be used, but if you don't know their prior history you don't know how much service life is left.
Three strings of 22 of the C-D caps will give you .02uF at 44KV, which should give very long life in your coil if you maintain a reasonable spark gap breakdown voltage. Go to the C-D website and use the "Part Search" function to check distributor stock. Right now, DigiKey, Richardson, Allied, Waldom, and TTI show stock. Contact these distributors to find your best pricing (Richardson is showing $3.63 each in quantities of 50).
Registered Member #4082
Joined: Wed Aug 31 2011, 07:57PM
Location: wolverine lake MI
Posts: 5
yeah, its about what i was afraid of, expensive no matter what you do. thanks for all the help Herr Zapp, i think i have a final design, and JAVATC predicts 43" sparks ;)
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.
Where to buy primary windings?
