15kv 30ma Tesla Coil

Here is a detailed "parts list" The secondary coil is about 1000 turns of 30awg wire wrapped around a 2.5" by 16" PVC pipe. The primary coil is 1/4" copper pipe I got in a 50' length from Lowes. The power supply is a 15kv 30ma neon sign transformer me and my dad traded a few watermelons for it at a neon sign shop. The capacitor bank is 56 1.6kv .022uf capacitors wired in series and parallel to get the required voltage and capacitance of 22.4kv and .0063uf. The spark gap is a 5 gap design with six 3/4" diameter copper tubes. The base is cut from plexiglas i got from home depot and is 18"x18". The white plastic supports for the primary coil are cut from a cutting board. The top load is 4" dryer duct wrapped with aluminum tape sandwiched between two 6" pie pans which are bolted together with a nylon bolt. I got the various nuts and bolts from my local hardware store

[@bencawter]

The efficiency looks like it’s at 110%! Great job

[@harms123]

Nice build. Quick PSA for newbie tesla coilers: Don't build this unless you know what you're doing. High voltage can be amazing, beautiful and educational, but also extremely deadly. A spark gap coil is often simpler to get working but a lot more dangerous than a solid state one. Do your research, stay safe, really do your research and have fun. Also don't play around with microwave oven transformers. Those are a one way ticket to the afterlife.

[@inventorbrothers7053]

Cool! Those are some very large sparks.

[@flaplaya]

Very nice tuning young sir 👏

[@solarsynapse]

Awesome! No filtering for protection?

[@therealprofessor976]

What is equivalent of the capacitors you used in the coil?

[@paparoni100]

What are you going to do with noise??

[@Sima-kumari]

Very good

[@KeystoneScience]

Awesome video !! Out of curiosity, where did you buy your capacitors from?

[@PulsedPower]

Hi, I believe I purchased them on eBay.

[@Felisargyle]

Keystone Science I found you haha you have been recognized

[@nicholasmarcus5594]

do not ground your secondary into the house ground I did it and now all the lights in my house have been flickering for like a month.

[@jessicaganser2982]

Just conect it to a water pipe or a heater.

[@maximusatomicus4103]

Hello, can you ask me a question? So I investigated whether or not you have to use AC capacitors. And you are using DC that burns out due to voltage peaks, so you have to apply double the voltage. This is false?

[@squalus392]

Where did you get the nst? That's the only thing holding up my project. Cant seem top find one without gfci.

[@PulsedPower]

Check google for neon sign shops in your area and go ask them if they have any untested (or otherwise) NSTs that they would be willing to trade, sell, or give to you.

[@redoverdrivetheunstoppable4637]

pretty good watermelons :D

[@sajalyadav989]

Hi Ben, I'm using a 2x7.5kV NST. So for 15kV, I use two 7.5kV outputs. But where should I connect the second terminal of primary coil (first one to cap bank)? And will there be no actual ground in my primary circuit (will that be an issue)?

[@PulsedPower]

Hi Sajal, Your second transformer output should be connected across your capacitor (in parallel). Essentially your HV transformers will be in parallel with your capacitor and the primary coil + spark gap (which are in series). Transformers||Caps||(primary+sparkgap)

[@davidboggs4969]

put a small fan on your spark gap , old vac cleaner , muffin etc

[@AirrwgryMayak]

I used C.100uf can it help me

[@engincoskun6620]

Hello There; I made the tesla coil, the features of which are written below, but the spark coming out of the top load is 3 cm. What should I do to increase the output spark length? Neon Transformer: Input 230 VAC.Output 15 KV 30 mA Sparg Gap Spacing : 10 mm Primary Capacitor Circuit: Ceramic Type 2.5 nF 40 kV (4 pieces of 10 nf 10 kV connected in series) The resistor was not used. Primary Coil (primary): 9.56 mm Copper Air Conditioning Pipe Winding Shape : Spiral Coil Space Between Windings: 10 mm Number of Rounds : 11 Rows Measured on a frequency of 1 KHz with a Primary Coil LCR Meter. Inductance (L) = 0.04 mH Secondary Coil : Copper Wire 0.40 mm. Copper Wire Length 475 meters. Coil Diameter : 110 mm. Coil Length: 550 mm Number of Rounds : 1375 rows The Secondary Coil was measured with the LCR Meter on a frequency of 1 Khz. Inductance (L) = 33.4 mH Toroid : Aluminum Aspirator Ventilation Pipe Channel Diameter: 130 mm Toroid Total Diameter : 400 mm Toroid Center Inner Diameter : 160 mm

[@fakeworld6822]

Hello, What Brand NST is that? Can you post a link?

[@SaintTrinianz]

I'd need more than a parts list and a few watermelons to put this together...

[@nirvana2117]

Hey how many of those capacitors did you use and what's there voltage rating and capacitance if you know it?

[@PulsedPower]

See the video description!

[@pavelroden4799]

Hi, you wrote your capacitor has 0063uF , you think 63nF or 6.3 nF?

[@user-lg7cb6sr5z]

Google it

[@kenechipalabrica9602]

Im confused where am i gonna supposed to connect the secondary in the earth?or in capacitor?

[@PulsedPower]

kenechi alviar Yes you can connect it to a copper rod that you pound into the ground.

[@TylerSmith-kt8rk]

Hello, what type of resistors are you using on the capacitors? I can't make them out in the video

[@PulsedPower]

Tyler Smith Hi Tyler, They are just standard metal oxide resistors, nothing special. I don’t remember the exact values but probably 1 to 10Meg and 1 or 2W. Larger wattage is helpful just for the physically larger size which will prevent any chance of voltage breakdown.

[@TylerSmith-kt8rk]

@@PulsedPower Thank you, Ben!

[@imanb608]

Hi, I know it's been about 6 years but I have a question! I know for sure that the output of this NST transformers is AC, and AC could not charge capacitors, how could you charge your cap-bank directly from AC power supply without using a Diode?

[@PulsedPower]

Hello, good question! When you say "AC doesn't charge capacitors" you must consider the time scale and size of the capacitor. In our case, the AC signal is pretty low frequency (60Hz) and the capacitance is very small. This means that the capacitors can easily be charged up to a voltage that is greater than the breakdown voltage of the spark gap in each HALF CYCLE of the AC. So, for each positive AND negative half cycle of the AC NST the caps are charged, the spark gap breaks down allowing the caps to discharge through the primary, this primary current induces current in the secondary, and sparks fly! So basically the capacitors charge up and are discharged 120 times per second (120Hz). They dont care whether they are being charged up by a DC source or just half of an AC cycle.

[@imanb608]

@@PulsedPower thanks

[@maxik444]

good

[@nirvana2117]

Hello do you recall what diodes you used for this coil?

[@PulsedPower]

No diodes needed! Its all running on AC. Each AC half cycle charges up the capacitors, reaches high enough voltage in mmc to jump the spark gap, and therefore dumps the energy through the primary coil exciting the secondary. And so on each AC half cycle.

[@randygray8273]

I'm using the same transformer. Where did you get the capacitors?

[@PulsedPower]

Hi Randy, I purchased them on ebay, however I dont remember the seller name or anything. *after doing a quick search I found these, which I think are equivalent or identical to what I purchased: rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F391687467472

[@randygray8273]

@@PulsedPower thanks

[@cphVlwYa]

Hey, I'm planning on building one of these but what is the overall capacitance of the capasotor bank?

[@PulsedPower]

Yextus Hi, the overall capacitance of my capacitor bank is .0063uf and a voltage rating of 22.4kv. however, for your tesla coil it will most likely be different. you will want the voltage rating to be roughly 1.5 times that of the power supply and the capacitance can be calculated with this extremely helpful program. here is a download link, just download it then extract the zip file and run the application. tesla-coil-cad.software.informer.com/2.0/ Remember, adding capacitors in series will add the voltage but add the inverse of the capacitance (eg. 1/(C1+C2+C3...Cn)). and adding them in parallel will double the capacitance and the voltage will stay the same. If you have any questions let me know and i will answer them the best i can. There are alot more knowledgeable sources on the internet that you might want to search for.

[@cphVlwYa]

Ben Watson Thanks, and wow that is a really helpful program

[@pawel5763]

how many air is between the copper tubes?

[@PulsedPower]

MountainCrafter6 it was about 1/4” air gap

[@user-gr5qb2iv8w]

Hello Mr Watson. Explain please why flat primary coil better than cylindric? Excuse me for bad English im from Belarus)

[@PulsedPower]

Hello! The flat primary is not inherently better than cylindric, but in many cases it is preferred. The main difference between a flat primary and a cylindrical primary will be the coupling factor. A flat primary will have lower coupling which is usually what you want for tesla coils (although you will see some QCWDRSSTCs that use cylindrical coils because they want higher coupling). The flat coil will also have a more uniform coupling factor between all of the secondary turns whereas a cylindrical primary will have a high coupling to the lower turns on the secondary but a low coupling to the upper turns on the secondary, this can lead to over-stressing the lower secondary turns causing them to arc.

[@user-gr5qb2iv8w]

@@PulsedPower thank you so much

[@devalthedevil7482]

Hi, I tried building a similar tesla coil, with a 12kV NST and a 4” PVC, however while the spark gap..capacitor bank, and primary coil worked..no sparks were visible from the discharge terminal. I’m guessing the secondary didn’t get powered but have no clue why.

[@PulsedPower]

Assuming you have approximately correct values chosen (capacitance and inductance) for proper primary-secondary frequency matching, you will still certainly have to tune it. The easiest way is to have one of the connections to the primary coil be a moveable tap of some sort (like the aligator clamp on mine). Then start at one extreme and move it bit by bit (completely diaconnecting power to the coil and discharging the caps each time before touching it of course) until you start to see some streamers. Having a breakout point will help as well.

[@devalthedevil7482]

Ben Watson i have a tap on 7.75 turns for a 50feet primary..but no breakout point..I’ll add that and see what happens. Thanks.

[@devalthedevil7482]

Moveable Tap..I’ve tried moving it around to no avail but breakout point may help

[@superkoksu487]

How long is the pipe you used as primary in meters?

[@PulsedPower]

super koksu I believe I got a 25ft refrigeration coil from Lowe’s. That would be just about 8 meters.

[@superkoksu487]

thank you :)

[@solarsynapse]

Looks like you wound the primary counterclockwise. Which way did you wind the primary?

[@fecklesstech929]

I've built several small and medium sized Tesla coils over the years. I've never even checked to see which way I'm winding my primary and secondary coils. It doesn't matter.

[@solarsynapse]

@@fecklesstech929 Hmmm, it is a transformer and it does matter for them for phase, so I thought it would matter for a Tesla coil. I have temporarily given up trying to make mine work. I can turn the primary over, but would be a lot of work.

[@fecklesstech929]

@@solarsynapse I'm a tech, not an engineer. However, I think if the primary & secondary are wound in the same direction, the voltages are 180 deg out of phase, and in phase if they are wound in opposite direction. Regardless--if a TC is properly tuned there's no measurable performance difference. Some TC builders claim the "wrong" phasing increases the chance of a HV breakdown between the base of the secondary and the inner turn of a pancake primary. This seems unlikely since the base of the primary is supposed to be grounded, and therefore at 0v. My first TC was no bigger than a toilet paper tube and was powered by a car ignition coil. It worked fine. My last Tesla coil was wound on 6" PVC pipe, was powered by a 5kW pole transformer, and threw a 7 foot spark. In between I built a half-dozen or so medium-sized devices powered by NSTs and MOTs. All of them worked. I've never paid any attention to winding direction.

[@solarsynapse]

@@fecklesstech929 Thanks for the info. I really like the one in this video.

[@devalthedevil7482]

How were you able to assemble the primary coil so beautifully!

[@PulsedPower]

I used refrigeration tubing which comes in a coil, so that helps but obviously you still have to gently bend it more to get it into a spiral. I used some hdpe material for the coil forms. I basically drilled correctly spaced holes on it and then cut it on a table saw leaving me with a bunch of semicircular slots in the top of each piece into which I could press the copper tubing. As you can see this does a pretty good job of holding it in place and in form.

[@devalthedevil7482]

How did you mount the secondary?

[@PulsedPower]

@@devalthedevil7482 I used a PVC pipe flange that allowed me to bolt the pipe to the upper platform with 4 nylon bolts.

[@engincoskun6620]

Classic type spark gap I am making Tesla Coil. I have a few questions to ask you. I would appreciate if you help. I use a 15 kV 30 mA Neon transformer for the input. I used a ceramic type capacitor for the primary capacity. capacity 25 kV 30 nF. Capacitor information 6 pieces 10nF 10 kV. 6 pieces 10 nF 15 kV. If I connect a parallel 10 Megaohm resistor to each capacitor for fast discharge, will the tesla work correctly? Will it be enough for insulation if I cover the capacitor leg connections with silicone? Spark gap distance 13 mm is enough? I used 10 mm copper tube in the primary coil. I wrapped 10 turns. How many mm should the connection cable between the capacitors and the copper tube? I have 1 mm copper wire for the secondary coil. How many times will the number of turns of the secondary coil be? There is a 50mm diameter and 400 mm long plastic pipe. How many turns should I spiral to resonate correctly? When the process is finished, what is the spark length in the end when testing? Which equipment do we need to cool when we make this circuit? Does over-winding of the secondary coil cause overheating? Is it necessary to cover the secondary winding with varnish? If you answer this e-mail, I would appreciate it if you could help.

[@PulsedPower]

Far too many questions to answer coherently in a KZbin reply. If you need a response to all of these send me your email address and I can formulate a reply. But FIRST I would suggest googling “JavaTC” which is an online and downloadable Tesla coil calculator that will answer many of the questions you have here. I also suggest searching for answers on 4hv.org and highvoltageforum.net you can also make an account there and ask questions in a forum post.

[@engincoskun6620]

@@PulsedPower thank you so much. my email adress : [e-mail]

[@Observ45er]

Ben, Please read my comment under your Veritasium light bulb video. I have yet to see anyone familiar with transmission lines make this observation that I have.

[@g-gon8869]

30 milliamps you kidding me dude? That coil is huge

[@PulsedPower]

15kv 30mA is referring to the NST feeding the coil.

[@g-gon8869]

@@PulsedPower ooh I see,sorry my mistake

[@BIGRIP87]

what is the type of capacitor is it polypropylene or polyester?

[@PulsedPower]

I dont believe they specified, they were cheap ebay caps. I think they were just called metalized film capacitors, if I had to guess id say Polyester.

[@BIGRIP87]

@@PulsedPower oh 👍👍

[@Tripp77]

Maybe you can help me?.. I have tried so many wiring methods for a Tesla coil but I can't get it to work for the life of me. I have a 5kv neon transformer, connected a positive to a high voltage capacitor, then to the primary coil. Had the other one go to a spark gap then to the primary coil.. had the secondary lower wire grounded and the top connected to a foil ball. The spark gap works but the Tesla coil doesn't. I tried an earth ground for the secondary. I tried without the capacitor. Tired have the capacitor before the spark gap. Even tried hooking the secondary up to the positive of the transformer. it... even tried other separate secondary builds and primary.. I.. don't.. get.. please help..

[@PulsedPower]

If it is an ac transformer then there shouldn't be a positive or negative output. Is it labeled positive and negative? What is the voltage and capacitance rating of the capacitor you are using? and is it an electrolytic type? (aka is it labeled positive and negative) Do you know about how many turns are in the primary, and the secondary?

[@scotlahnmccallister1171]

+Ben Watson What he is talking about is the output of the transformer. There is a positive and negative output of the NST. It seems like the only issue he's having may be his primary coupling. Is the primary too far from the secondary to magnetically couple the two coils? If it isn't then it may be his capacitor setup. He could possibly look up the diagram for a tesla coil online, and see how to fix the capacitor issue. Just ask if you need more help, or if you want to point something out I may have said incorrectly.

[@camerongallo5940]

NSTs are alternating current so Ben is right, there shouldn't be a negative or positive. Also 5kv is a bit low for a tesla coil transformer. I believe you need at least 9kv to have air ionize for the spark gap. However, you can make up for a low voltage transformer with a lot of capacitors.

[@Slowly_Going_Mad]

@@camerongallo5940I had no trouble using an electric fence transformer that only puts out 600V boosted it to around 70kV, secondary coil thousand or so turns, primary six turns, homemade wax paper capacitor using five sheets of printing paper and four sheets of thin foil.

[@platinumscience7356]

Can you put a link to your capacitors

[@PulsedPower]

Heres the equivalent: rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F391687467472

[@ElectricUniverseEyes]

🤜🏿⚡️🤛🏼

[@oldchannel3266]

COOL .O.

[@typerightseesight]

how much?

[@randygray8273]

What's the inside diameter of the primary coil?

[@PulsedPower]

I dont know that actually. The secondary is wound around a 2 1/2 nominal PVC pipe which has an actual OD of 2.875". Hopefully from that you can get a good estimate of the ID of my primary.

[@randygray8273]

@@PulsedPower I used 3" pvc which has a outside diameter of 3 1/2" so I guess I cant copy off you lol

[@MuhRizkyRahadian]

excuse, can i get your journal foir building this? thanks

[@PulsedPower]

Muh. Rizky Rahadian Hi, I don’t have anything like that. But I am more that willing to help you out if you decide to build one!

[@MuhRizkyRahadian]

oh ya thanks a lot. i have some promblem in primary coil with the cooper coil size, i make this tesla coil for output 3 Kv and i don't know what size should I use for cooper coil. do you have any idea for that?

[@PulsedPower]

1/4" refrigeration tubing works well. Are you wondering what diameter you should use? or how long it should be?

[@MuhRizkyRahadian]

i really wondering what diameter i should use

[@florianlemmer5352]

Can you touch the arcs?

[@PulsedPower]

Not a good idea. Even if the 250kHz arcs dont "feel" like a shock, the can still cause internal burning. And if the secondary happens to short to the primary while also arcing to you, then you are connected to deadly 15kV at many amps straight to ground.

[@theplasmaprince8651]

Was there a safety gap?

[@PulsedPower]

Hello, yes there is a safety gap. You can see it at around 00:10, it is the two curved pieces of copper wire next to the transformer.

[@theplasmaprince8651]

@@PulsedPower is a grounded electrode required? or is it just the outputs connected to two electrodes.

[@PulsedPower]

@@theplasmaprince8651 In the safety gap no ground is required. Just needs to be across the transformer output.

[@theplasmaprince8651]

@@PulsedPower Okay, thank you for the clarifications! This helps a lot with my Tesla coil project!

[@PulsedPower]

@@theplasmaprince8651 Of course! Good luck and certainly stay cautious/safe. Dont let the fact that you havent had a serious accident cause you to become complacent. Starting out I certainly didnt have proper respect for how dangerous this hobby can be, but if you are willing to take precautions and exercise patience it can be extremely exciting and a great learning opportunity!

[@Sima-kumari]

🌷😃😃

[@mrbecope852]

How can i get u to make me one woth audio input??

[@PulsedPower]

Pay me a lot of money. Or use your money to buy something like the OneTesla! :)

[@mrbecope852]

Email me lets talk about how much u charge tcertifiedb @ ...gmail

[@barsaktas289]

Hello Could you tell the materials

[@PulsedPower]

Manyak Oyuncu See the description for details on what materials were used. You can find information on the theory and construction of tesla coils online. If you have any specific questions feel free to ask me!

[@barsaktas289]

thank you very much

[@brettmoore3194]

Where is the tuned reciever

[@PulsedPower]

Not present. The main goal was to make large sparks, not transfer wireless power.

[@brettmoore3194]

@@PulsedPower well , try super capacitors to give them that extra umph

[@PulsedPower]

@@brettmoore3194 In a spark gap tesla coil such as this all of the stages, from input power to output streamers, are AC. Super capacitors can only be used in DC circuits because they are polarized. A solid state tesla coil, where the AC input is first rectified to DC, could possibly use super capacitors, but I believe that large electrolytics would be preferred due to their voltage ratings.

[@brettmoore3194]

@@PulsedPower the original tesla circuit used dc. And a distilled water capacitor in parallel with the super caps would give you the voltage gradient needed.

[@marciooppido206]

15KV? friend only the neon transformer has it.

[@PulsedPower]

I am aware of that. I thought it would be best to categorize it by its input power since the output is harder to determine and will vary depending on the tuning.

[@PulsedPower]

BGW ELECTRIC Thanks! Yeah that seems reasonable.

[@marciooppido206]

I understood, cool your design, I believe the output voltage is about 150KV - 200KV, my faculty professor of engineering college made a coil test with the secondary with 6000 turns, it produced 1 meter of spark in the dry time, 1 Million volts

[@TheCORC964]

dare you to touch the sparks

[@platinumscience7356]

can I used my zvs flyback set up for this for this its around 10kv and 30-50 ma

[@PulsedPower]

Platinum Science Do you know if the output is rectified or not? I would recommend rectifying it. otherwise im not sure how the frequency of the fly back would work with the capacitor bank and spark gap.

[@platinumscience7356]

Ben Watson yes it has a built in rectifier

[@johnbatchler8551]

You house electrical system is going to be flickering

[@user-tb4sl4ex2q]

Don't do that inside please.

[@SERGEY-KACHAN]

Видео "Трансформатор TESLA": kzbin.info/aero/PLlEX99xZE8qNc1MNp9EwjbeugLTRhr-9g

[@FFFF-ic6rb]

good

[@pavelroden4799]

Hi, you wrote your capacitor has 0063uF , you think 63nF or 6.3 nF?

[@PulsedPower]

Pavel Roden Hello, .0063 uf would be equal to 6.3 nf. One trick is to move the decimal place 3 places to the right since you are going from micro-farad 10^(-6) to nano-farad 10^(-9)

[@pavelroden4799]

Ben Watson yeah, sorry i wasn't sure, thanks, i'm just verifying

[@barsaktas289]

Ben Watson Hello Could you tell the materials

[@pavelroden4799]

manyak, i think , Ben has Neon Sign Transformer, to 15kV 30mA , capacitor 6.3 nF, you must just watch the video ;)