Sry I missed this post. Does this still apply that I fried all 4? Seems like it, you tell me...Okay, for sure, Ill lower my 50% duty on my reset pin to 25% arduino signal, and Ill test that on my low power supply. I will make a video to show how as I add turns on primary it just dies.. maybe is just too weak of a power supply?This suggests that you had too much current passing through the primary coil. There are two possible reasons that I can think of right away that can cause that: Too high of a pulse width and too few primary turns. Both of these could very well be the problem, considering you said you only have a few turns on the primary coil. It might be time to start focusing on why you can't get it to work with more turns. Instead of acting like an inductor that restricts alternating current flow, the primary coil may have acted more like a low-ohm resistor, allowing too much current through. The easiest thing to change right now, however, is your pulse width. Replace the FETs and try a lower duty cycle and see if that helps anything. From there we can look at increasing the number of turns on the primary coil.
Your scope does "suck" and you're still not seeing the entire picture because of its low bandwidth. It's incapable of capturing the high-speed events that are very important to see when playing with Tesla coils.A side note here, You say my scope sucks but from what I see the 74HC14 is faster but the CD40106 outputs a 30% cleaner signal from what I see...Is this chip fried? I have another to try..pictures are labeled below.
I don't need to try one because you're already showing me images from it which prove my point (though you have no point of reference of what a good scope should show in this case, so you aren't seeing how awful it really is). Sure, it may do the trick for basic projects, like automotive ones. I'm not complaining about that. I'm complaining about you insisting to use it for this project where it isn't even beginning to do what we really need it to do. I certainly encourage you to move forward with a higher BW scope. A simple Rigol DS1052e is one of the cheapest on the market and yet will do most of what is needed for Tesla coil projects and a wide variety of other uses. I wouldn't get anything cheaper though, because it is on the brink already.Dude you have gatta get over the scope, Yes it does not have that high of bandwidth, But put this next to a benchtop 1Mhz scope you would be impressed. So for what it can do it does not suck. I think it just sucks in your mind because its not the proper scope for this project, which your right. I got this for Vehicle testing and it has never failed me once. Maybe if you tried one your opinion may change. I will most likely get a higher bandwidth scope soon. I am loving this hobby and my later want to make a DRSSTC.
I'm wondering if the junction capacitance of the clamping diodes is coming into play (I'd have to do some more digging into datasheets). If the lower one was acting as a capacitor it would shunt the output from the CT to ground, thus giving you a flat line into your logic. I have never seen this happen, and I wouldn't expect the junction capacitance to be a problem until you get into extremely high frequencies, but I can't say for sure. Then again, if this was the problem then I wouldn't think placing the DC-blocking capacitor before them rather than after would make much of a difference.... I'll take a look at the datasheets when I get home from work if I think of it.Any thoughts on the CT working like that?
You said P = I^2 * R for Mosfets, So Bellow I wasnt doing that.You're using MOSFETs. There is a reason Guangyan used IGBTs in his design. At the high currents seen in a Tesla coil H-bridge, the MOSFET acts as a resistor, and the power dissipated is P = I^2 * R. IGBTs have a fixed voltage drop, however, so the power dissipation is only P = I * V.
So is it really P = 13a^2 * 100v ? cuz thats 16900W/4 = 4225 watts a piece? I'm lost....LOL sry.... But shouldnt I be close to popping these at 15amp? Sure they say 50amp but 250v @ 50amp aint anywhere near 400W which is there rating.. Just on my mind since all four blew, thats never happend, and it seem to run great.So max 400W a piece, 15amp*100V=1500W/4=375W a piece? So am I 750W of 800W total or am I 375W of 800W total?
P = I^2 * R, not P = I^2 * V.Hey so this is a thought I had about what you said earlier:
You said P = I^2 * R for Mosfets, So Bellow I wasnt doing that.
So is it really P = 13a^2 * 100v ? cuz thats 16900W/4 = 4225 watts a piece? I'm lost....LOL sry.... But shouldnt I be close to popping these at 15amp? Sure they say 50amp but 250v @ 50amp aint anywhere near 400W which is there rating.. Just on my mind since all four blew, thats never happend, and it seem to run great.
The number of Schmitt triggers determines the phase of the output. If you only have one it inverts the signal from the CT (shifts it roughly 180 degrees out of phase). Adding a second trigger puts the output back in phase with the CT. If it works with one Schmitt trigger inverter, but you want to add a second one, then swap your CT leads and add the second inverter. This will put everything (roughly) back in phase. I say roughly because there are delays caused by C1, R1, C2, and your Schmitt trigger inverters that will also shift the signal slightly.
No, I read this thoroughly and understood it. You have to understand that you are not the only one reading this thread. Sometimes I need to explain certain concepts for the benefit of other current and future readers. The point of my post was mainly to look at the delays caused by the different parts of your circuits (i.e. the propagation delay of the Schmitt trigger inverters and of the RC filters). I think you need to go back and reread my posts as you clearly are not understanding the intent behind them.I have always been paying VERY big attention to my 180* shifts with toroid/connections/inverter count.
I think you didnt understand what I meant.. I am not flipping 180*... I was on one schmitt, then ran the secondary ground through the toroid in the opposite direction i had it. This flips 180. Then I added another schmitt, this adds another 180*. Now Im back "360*" to where I started. It runs very crappy with two schmitts(on same Phase cycle). I think it changes when adding one more schmitt due to the propagation delay the second adds.
I am assuming very little. I take what you write, I read it (often two or three times), and then I respond, sometimes adding background information for other readers, and to verify what you have already done. What has been holding us back this entire thread is you refusing to provide all of the necessary information. You STILL haven't posted any detailed photos of your setup, and all of the schematics you have posted are either incomplete or have been changed in your actual setup. All that on top of not using the right tools for the job makes it very difficult to help you.I really do understand you know a ton more then I do about this stuff but the one thing that has held us back this entire thread is you assuming I don't know something therefore I have to re-explain it. I understand my grammar might suck but you would have seen the part about the secondary ground if you where not assuming everything.
That's another thing, without detailed images from a high bandwidth scope, it's difficult to track down where your problem is. I know I've been saying this over and over again from the start, but that's only because it is more important than you seem to realize, and you just keep blowing it off. "Oh, this scope has worked fine for me in the past." "Oh, I plan to get a better scope sometime." None of this is helpful NOW, and expecting detailed help without providing decent waveforms, schematics, photographs, etc. is unreasonable.It will not work with no caps and through one schmitt, it will on antenna.... you saw my Previous phase shift on CT I'll test with my #2 setup and see If its less then the 1us the last shift was. I have tied a lot of combinations here and out of 115 this is the first one(#2)...
I answered this in my last post.What I was asking in that post is if it working with one schmitt is okay?
Changing the resistance to 56 ohms definitely helps the delay (your RC time constant is now 12ns) but now you have a filter that is practically useless (and FYI the fc with an R of 56 ohms and a C of 220pF is 12.918MHz, not 12.918kHz). Your filter wouldn't begin having an effect until the ~75th harmonic, which is absolutely useless. Theoretically you'd be better off taking it out altogether, which is what I mentioned earlier. We would need to determine the reason why adding a filter seems to be helping, and solve the problem further up the chain closer to its source. I think it's sheer chance that it is actually helping. The actual problem is most likely much deeper and you're just sticking a band-aid on it.Also my resistance has been changed to 56ohms. So 1/(2*pi*R*C) = 12918.42hz. does this make my RC constant better? Maybe this is moving me 180*out and if I invert that I'm back in to phase.?
you misread his and my schematic, stating I'm Making a DR.No, I read this thoroughly and understood it.
Then you assumed I was only flipping it only 180*, not 360*. this was two posts ago...The number of Schmitt triggers determines the phase of the output. If you only have one it inverts the signal from the CT (shifts it roughly 180 degrees out of phase). Adding a second trigger puts the output back in phase with the CT.
I did state I reversed my direction for secondary ground through the toroid. and added a inverter, this 360*'s my phase.Okay, so in this one I had to reverse the direction of the secondary "ground" through the toroid to 180 my phase, This alowed me to add another inverter.
This is absolutely false. Maybe on the first page but I would say your DR assumption was the BIG delay here.. I understand you need you need info and pictures, I dont recall one time you have asked for something I have not given. When I made my first post, I explained in detail that other then the bridge, which I made a schematic... I changed a few parts in his schematic. I explained exactly what parts......Another misrepresentation on your part is I did state in the start, I replaced his arduino with a multivib at 50%. you assumed I connected my output signal other then I stated. I said this Is the same but with a multiivib generating my signal.... But I dont recall one thing your still waiting on. Did I miss something again?What has been holding us back this entire thread is you refusing to provide all of the necessary information. You STILL haven't posted any detailed photos of your setup, and all of the schematics you have posted are either incomplete or have been changed in your actual setup.
I 100% agree with this, I am absolutely patching a mistake, not fixing it. So lets make this easier, I was 100 of on my khz calculation sorry, but RC constant how are you calculating that I thought R*C but thats off? What should My filter frequency be? Is this complimentary to my RC delay? Are there values here I should be shooting for?I think it's sheer chance that it is actually helping. The actual problem is most likely much deeper and you're just sticking a band-aid on it.
I do agree with this and Im sorry Im not going to go buy one right now. I also understand this isnt helpful right now, but that wont change for a couple months.That's another thing, without detailed images from a high bandwidth scope, it's difficult to track down where your problem is. I know I've been saying this over and over again from the start, but that's only because it is more important than you seem to realize, and you just keep blowing it off. "Oh, this scope has worked fine for me in the past." "Oh, I plan to get a better scope sometime." None of this is helpful NOW,
And as soon as I realized my mistake I acknowledged it and moved forward with the SSTC discussion.you misread his and my schematic, stating I'm Making a DR.
No I did not. I was simply explaining the concept, once again for other readers, of Schmitt trigger inverters shifting the phase, and the need to ensure the CT and output of the logic were in the correct phase with respect to one another. This was a general observation and explanation.Then you assumed I was only flipping it only 180*, not 360*. this was two posts ago...
I know, and that's exactly how I read it. See my above comment.I did state I reversed my direction for secondary ground through the toroid. and added a inverter, this 360*'s my phase.
I did not make any assumptions here. I know you used a multivibrator, and that was also shown in your schematic (which I appreciate, but wish it was kept accurate and up-to-date). This was never part of any sort of confusion. What post made you think I thought you were connecting the output of the multivibrator differently?This is absolutely false. Maybe on the first page but I would say your DR assumption was the BIG delay here.. I understand you need you need info and pictures, I dont recall one time you have asked for something I have not given. When I made my first post, I explained in detail that other then the bridge, which I made a schematic... I changed a few parts in his schematic. I explained exactly what parts......Another misrepresentation on your part is I did state in the start, I replaced his arduino with a multivib at 50%. you assumed I connected my output signal other then I stated. I said this Is the same but with a multiivib generating my signal....
PHOTOGRAPHS AND DECENT WAVEFORMS!!!But I dont recall one thing your still waiting on. Did I miss something again?
100 off? Try 1000x. BIG DIFFERENCE!I 100% agree with this, I am absolutely patching a mistake, not fixing it. So lets make this easier, I was 100 of on my khz calculation
RC time constant is R*C. You said you have a 56 ohm resistor and a 220pF capacitor. 56*0.00000000022 = 12.32ns.RC constant how are you calculating that I thought R*C but thats off? What should My filter frequency be? Is this complimentary to my RC delay? Are there values here I should be shooting for?
Then consider this thread on-hold for a couple months. We can't move forward without having some waveforms that actually show what's going on. I will not post in this thread again until you provide detailed photos of your setup and some good waveforms of the signals throughout the circuit (GDT primary, GDT secondaries, bridge, feedback CT, clamped & cleaned feedback, etc).I do agree with this and Im sorry Im not going to go buy one right now. I also understand this isnt helpful right now, but that wont change for a couple months.
expecting detailed help without providing decent waveforms, schematics, photographs, etc. is unreasonable.
that was a typo yes 1000X, I had my pico decimal place off100 off? Try 1000x. BIG DIFFERENCE!
I posted videos, after that, I don't recall you asking for photos.PHOTOGRAPHS AND DECENT WAVEFORMS!!!
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