5 filar specs

[Rob_Esq]

Hi Rob,

If you get a scope this will help you a lot. You need a good "h" wave with no extra triggering going on and the scope will show you that. With my ssg I started getting double triggering just around and above 600 ohms so I had to keep my resistance below that. Anything higher and I would get one or more spikes between my "h"s and that's not good, so the scope showed me the max resistance that was useable.

Robert

Hi again. I finally bought myself a scope, and have got it up and running.


Here are some screenshots at 1,000 ohm and zero ohms on the pot. As you can see, its not an 'h' wave - its more of an 'n' wave. For some reason its not spiking. The scope shows a rise of between 25-30V. I tried this at various different resistances, and also with a different gap size between the wheel and electromagnet, and on each attempt the result was the same: 25-30V. This explains why I'm unable to charge above about 13.5V, this question is though, why isn't my SSG spiking?

I was curious to know why the neon is lighting when the battery is disconnected, if its only achieving about 30V. This third scope screenshot shows a test I did with the battery disconnected. This was at a very low rpm, straight after starting it,since I did not want to damage my components. What I think this is showing is 5 spikes per magnet. The scope's display is at a different resolution here, and the spikes are actually at 60V, compared with the 30V max with the battery connected.

I'd really appreciate it if anybody could give me some insight into why its not spiking when the battery is connected.

Rob

[Robert Darrah]

Hi Rob,

Sometimes when the theory doesn't work and the troubleshooting skills just aren't cutting it, then you're down to your last resort, which is to be a parts changer. I've done it on my car at times when I just couldn't diagnose the problem, so I'd just try new parts until I found the problem. The ssg circuit is pretty simple and inexpensive, so maybe just solder up a new board and pop it in and see what happens. Or a different coil.

My electrical teacher used to look with scorn on parts changer. "If you're not a troubleshooter then you're just a damn parts changer!" Works for me!

Robert

[Rob_Esq]

Hi Rob,

I think the final arbiter as far as tuning goes is what kind of cop you get from a particular tuning. It's a laborious method, but you could try different tunings and see which gives you the best cop.

If you get a scope this will help you a lot. You need a good "h" wave with no extra triggering going on and the scope will show you that. With my ssg I started getting double triggering just around and above 600 ohms so I had to keep my resistance below that. Anything higher and I would get one or more spikes between my "h"s and that's not good, so the scope showed me the max resistance that was useable.

Looking at your chart, around the 700 ohm range the amp draws look about right, so I don't think you're that far off. Both charging and primary amps do increase as base resistance increases, so I think your amp draws look ok. It's the rpms that don't make any sense to me. I could adjust from 200 ohms up to 800 ohms and my rpms were 152 at 200 ohms and 147 at 800 ohms and they stayed in that range all the way through. I didn't get the wild increase that you're getting.

The way I see it you have 2 different issues. One is that you need to tune it and two is the strange rpm increase. I think you could separate the two issues, meaning forget about the rpms for now and just work on the tuning. Going by what my ssg would do, I think if you can charge a battery in 40 hours (what size battery do you have?) and it's somewhere around 700 ohms then the tuning isn't too far off.

If you're on the mp3 group I'd also suggest looking in the files section at other people's builds. That's what I'd do if I had questions. I'd try to find people that had a build similar to mine and see what results they got and where their sweet spots were. There was a wide variation in results between different builds and you can learn a lot from that.

If you were using a bike wheel and everything was per specs then it would seem your results should be similar. But if you're getting this huge increase in rpms and nobody else is, then something about your build is different. So if something is different you should be able to look at the original instructions and see what about your build is different, and hopefully that will point you to why your rpms increase like that.

Robert

Hi Robert. Yes, I'm on the verge of buying my first scope, so hopefully I'll have a better idea what's going on in the near future. Separating out the tuning and rpm issue is a good strategy, assuming they're unconnected issues, which I'm not sure they are, especially given the (relative) simplicity of the system. Lacking any other strategy however, I'll take your advice. I'm currently charging a 6Ah SLA (motorcycle) battery. The annoying thing is that in a previous build, before the 'improvements', I was able to charge up to 14.5V in 40hrs.

I must admit that somewhere along the line, with all this tinkering, I've lost track of how many winds are on the coil. It looks less than the specified 850 - I think I'll rewind the coil again as my next move, and check this is to spec. First I'll give it a whirl at 700 ohms though and see how this goes.

Thanks for the advice .. Rob

[Michael Luton]

Hi Theuns. Can you not see the photo of the circuit in my previous post, or do you mean that the photo is not clear enough? (I can add some clearer photos of the circuit if it helps.) Both of my previous wheel builds were bicycle wheels, and had the same phenomena: high resistance = high rpm / low resistance = low rpm.

What effect do you think that low momentum would have on performance? The wheel is actually quite heavy because it has a lot of magnet in it, but it has a very low free spin time. This is compensated for by lack of drag - the wheel is fast and efficient.

Rob

The circuit schematic that you are using is not available, and the pictures of your circuit are not clear enough. It appears as if your trigger is connected to the collector and the only thing connected to the base is the diode.

[Robert Darrah]

Hi Rob,

I think the final arbiter as far as tuning goes is what kind of cop you get from a particular tuning. It's a laborious method, but you could try different tunings and see which gives you the best cop.

If you get a scope this will help you a lot. You need a good "h" wave with no extra triggering going on and the scope will show you that. With my ssg I started getting double triggering just around and above 600 ohms so I had to keep my resistance below that. Anything higher and I would get one or more spikes between my "h"s and that's not good, so the scope showed me the max resistance that was useable.

Looking at your chart, around the 700 ohm range the amp draws look about right, so I don't think you're that far off. Both charging and primary amps do increase as base resistance increases, so I think your amp draws look ok. It's the rpms that don't make any sense to me. I could adjust from 200 ohms up to 800 ohms and my rpms were 152 at 200 ohms and 147 at 800 ohms and they stayed in that range all the way through. I didn't get the wild increase that you're getting.

The way I see it you have 2 different issues. One is that you need to tune it and two is the strange rpm increase. I think you could separate the two issues, meaning forget about the rpms for now and just work on the tuning. Going by what my ssg would do, I think if you can charge a battery in 40 hours (what size battery do you have?) and it's somewhere around 700 ohms then the tuning isn't too far off.

If you're on the mp3 group I'd also suggest looking in the files section at other people's builds. That's what I'd do if I had questions. I'd try to find people that had a build similar to mine and see what results they got and where their sweet spots were. There was a wide variation in results between different builds and you can learn a lot from that.

If you were using a bike wheel and everything was per specs then it would seem your results should be similar. But if you're getting this huge increase in rpms and nobody else is, then something about your build is different. So if something is different you should be able to look at the original instructions and see what about your build is different, and hopefully that will point you to why your rpms increase like that.

Robert

[Rob_Esq]

Rob_Esq

Yes I can now see the the photo's,

Do you mean higher resistance (on the pot) = less amp draw on the meter from the primary, or is it the other way round ?

When you start your wheel, how many times do you get the peak amps go-up and drop back on the meter as the wheel picks up speed? I think you need just that little more amps to push it over to the next (gear) with a bit more amp draw to get to the higher volts on the secondary.

Do you know of any one else that built a styrofoam wheel that is working fine?, Maybe on this one Gurus can chime in on this one.

Theuns

Hi Theuns.

Here is a graph of my pot vs. primary draw, with RPM, and number of gear shifts up to full speed. (This is with a gap of about 2.5 - 3.00mm on the coil - no doubt it wld be a lot different with a different gap.) Quick answer to your question: Yes, I mean higher resistance on Pot equals less draw on primary battery, plus higher RPM.



As you can see the ratio of RPM to primary draw is over 3x greater at maximum resistance, than it is at minimum. Can you see why I'm having problems tuning it .. going from these figures, how else would you adjust it, other than at full resistance?

[alfinip2000]

Prinsloo,if i were you..ill try to make as close as possible to JB spec..ive been adventrous and make ssg from wheel to wood.duff transistor etc...what igeve found is the closer to jb spec..the better the result(also save more money ) as long as you can learn nothing to loose then..cheers
Alfin

[Prinsloo]

Hi Theuns,

I just meant did you ohm all your solder joints with an ohmmeter. As I'm soldering my board I'll check each connection with an ohmmeter to make sure it's a good joint. Then after it's done I'll go through the board again just to double check, as the board is out and it's easy to do.

A poor joint would have high resistance and an ohmmeter would show this. Right now you're using 22 ohm resistors and it sounds like the resistance is still too high, so you might have a bad joint, or something that's adding resistance to the trigger circuit in addition to the resistors. That's what sounds most likely to me at any rate.

Especially check that you got all the insulation off the magnet wire where you soldered it. I scrape it with a utility knife and then sand it after that. You'll see the color change and you can see the fresh copper of the wire so you know you got it all off. Then put your ohmmeter on both ends of the magnet wire and ohm your coil to make sure the insulation is all off and you have good connections at both ends.

You can't go much lower than 22 ohms on the resistors, and if it doesn't even move at 100 ohms it sounds like it's not even close to being tuned, so I don't think a lower resistor is going to do it. I'd really be looking for extra resistance somewhere that shouldn't be there.

Good luck!

Robert

Hi Robert

Thanks for the advice I did the resistance test and found 1 coil wire not connected and 1 of the base resistor wires was a dry connection. We test it further this weekend.

Theuns

[Prinsloo]

Rob_Esq

Yes I can now see the the photo's,

Do you mean higher resistance (on the pot) = less amp draw on the meter from the primary, or is it the other way round ?

When you start your wheel, how many times do you get the peak amps go-up and drop back on the meter as the wheel picks up speed? I think you need just that little more amps to push it over to the next (gear) with a bit more amp draw to get to the higher volts on the secondary.

Do you know of any one else that built a styrofoam wheel that is working fine?, Maybe on this one Gurus can chime in on this one.

Theuns

[Rob_Esq]

Hi Rob_Esq

My 2c of newbie help, (you need to re-post your circuit diagram so that we can see what is going on and not speculate, cause this will just frustrate you even more)

Maybe your new styrofoam wheel does not have enough momentum ?
Theuns

Hi Theuns. Can you not see the photo of the circuit in my previous post, or do you mean that the photo is not clear enough? (I can add some clearer photos of the circuit if it helps.) Both of my previous wheel builds were bicycle wheels, and had the same phenomena: high resistance = high rpm / low resistance = low rpm.

What effect do you think that low momentum would have on performance? The wheel is actually quite heavy because it has a lot of magnet in it, but it has a very low free spin time. This is compensated for by lack of drag - the wheel is fast and efficient.

Rob

[Prinsloo]

Hi Rob_Esq

My 2c of newbie help, (you need to re-post your circuit diagram so that we can see what is going on and not speculate, cause this will just frustrate you even more)

Maybe your new styrofoam wheel does not have enough momentum ?



Theuns

[Rob_Esq]

ok I cannot see your diagram, but your pot is wired backwards most likely, it depends upon which legs you have attached. if you have the left solder point and the center soldered, turning to the right will increase resistance. use your meter on it.

Tom C

Hi Tom. I don't think its this. I just tried swapping the connections on the pot as you suggested, but I still get the same effect .. just that have to twiddle the pot in the opposite direction. With maximum resistance its running at a cool 300 rpm (100 mps), and with minimum resistance this drops to around 206 rpm.

A few months ago I spent a lot of time trying to tune it as per the manual, but the results were always the same - the higher the resistance, the faster the spin. I even added 2 x 1K extra resistors at one point to see what happen - and the spin got even faster still. This would be great, except that I'm not getting any extra performance for the extra spin.

A while back I was getting successful charges up to 14.5V, in about 40 hours. I've pretty much rebuilt every aspect of the SSG (supposedly improving) since then though, so I cannot reproduce these conditions. The last major thing I did was to create a styrofoam wheel (see photo) with very little drag, and ceramic wheel bearings, which I am very pleased with, because it flies round with very little energy input. This increased my rpm by over 50% on the previous wheel, with less amp draw. My pleasure soon turned to dissapointment though, when I realised that it wouldn't charge above about 13.75V.

I've been stuck at this point for a good few month now. I am unable to progress with my 20 test runs: a. because I've never felt like its been properly tuned, and b. because I am no longer able to charge up to the required 14.5V.

(On the plus side, I have built myself an 8 filer coil while I've been trying to get the vanilla SSG working properly, which I'm looking forward to putting to the test

Rob

[Tom C]

ok I cannot see your diagram, but your pot is wired backwards most likely, it depends upon which legs you have attached. if you have the left solder point and the center soldered, turning to the right will increase resistance. use your meter on it.

Tom C

[Rob_Esq]

Higher resistance = higher RPM - surely this can't be right??

Hi all. I've been tinkering with my SSG for nearly a year now, and feeling frustrated because the tuning instructions have never made sense. Basically, the higher the resistance I adjust the pot to, the faster the wheel spins. I've been scratching my head for a while now wondering how this works - surely more resistance should equal less current into the base of the transistor = lower RPM? Now I've just finished reading this thread, and Tom says clearly that "it is a non linear increase in wheel speed as you drop in resistance on the trigger circuit". Can anybody suggest what I might be doing wrong? Here is a photo of my circuit:


Rob

[Robert Darrah]

Hi Theuns,

I just meant did you ohm all your solder joints with an ohmmeter. As I'm soldering my board I'll check each connection with an ohmmeter to make sure it's a good joint. Then after it's done I'll go through the board again just to double check, as the board is out and it's easy to do.

A poor joint would have high resistance and an ohmmeter would show this. Right now you're using 22 ohm resistors and it sounds like the resistance is still too high, so you might have a bad joint, or something that's adding resistance to the trigger circuit in addition to the resistors. That's what sounds most likely to me at any rate.

Especially check that you got all the insulation off the magnet wire where you soldered it. I scrape it with a utility knife and then sand it after that. You'll see the color change and you can see the fresh copper of the wire so you know you got it all off. Then put your ohmmeter on both ends of the magnet wire and ohm your coil to make sure the insulation is all off and you have good connections at both ends.

You can't go much lower than 22 ohms on the resistors, and if it doesn't even move at 100 ohms it sounds like it's not even close to being tuned, so I don't think a lower resistor is going to do it. I'd really be looking for extra resistance somewhere that shouldn't be there.

Good luck!

Robert