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Author Topic: Tesla's "COIL FOR ELECTRO-MAGNETS".  (Read 425653 times)

Offline gyulasun

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #750 on: January 21, 2014, 07:00:45 PM »
....

I will proceed to tests with air core. I have a Ferrite rod which just does not fit into the hole of the coil. I will try to widen the hole a little bit. But I do not want to do that till I have enough measurements with air core and steel bolt core (the coil might be damaged when manhandling it).

 Greetings, Conrad

Hi Conrad,

Okay, just do your schedule as you wish I have no intention to "divert" anything.

In your above tests,  you used the same 10 uF tuning capacitor?

The DC resistance establishes a basic coil loss resistance and this latter establishes mainly the current via the coil: hence this influences the core's excitation I believe.

Gyula

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #750 on: January 21, 2014, 07:00:45 PM »

Offline conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #751 on: January 21, 2014, 07:08:12 PM »
Hi Conrad,

Okay, just do your schedule as you wish I have no intention to "divert" anything.

In your above tests,  you used the same 10 uF tuning capacitor?

The DC resistance establishes a basic coil loss resistance and this latter establishes mainly the current via the coil: hence this influences the core's excitation I believe.

Gyula

@Gyula: I always used the same 10 µF capacitor (yellow thing, I only have three, and two are in a box). No problem with suggestions, you are not diverting, you are teaching.


New test with air core (all the same, only the steel bolt was removed and coil is a bit closer to spinning magnet, 3 mm gap):

wires in series, air core (DC resistance 97 Ohm)

125 Hz, no load, motor consumption 7.3 V and 1.18 A
             load, motor consumption 7.3 V and 0.94 A, speed rises to 133 Hz


For comparison:

wires in series, mild steel core (DC resistance 97 Ohm)

52 Hz, no load, motor consumption 4.4 V and 1.7 A
            load, motor consumption 4.4. V and 1.09 A, speed rises to 68 Hz


For test with only one wire (mild steel core) see: http://www.overunity.com/13460/teslas-coil-for-electro-magnets/msg384176/#msg384176
 
Greetings, Conrad

Offline conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #752 on: January 21, 2014, 07:17:54 PM »
Just a thought - your bearings & supports are quite far apart - which is probably why you have the vibration problem. If you were to move the bearings closer to the center of the shaft, it might help.

@tim123: yes, of course, but I wanted some space left and right of the spinning magnet for bigger pan cake coils. Thank you, every observation helps and brings me forward.

The biggest unbalance is the magnet, one even sees how one halve is slightly bigger than the other. I might try some counterweight on the axis.

Greetings, Conrad

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #752 on: January 21, 2014, 07:17:54 PM »
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Offline Farmhand

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #753 on: January 21, 2014, 07:33:00 PM »
The thing I looked at with the speed up under load effect is the dismal output as compared to the input, overall a faster rotor is not output, the power dissipated by the load resistor is the output, and the input compared to that.

Conrad try this if you don't mind, set the arrangement to the resonance point you get at 52 Hz or whatever it is how you have it, then after connecting the load adjust the drive motor to try to increase the voltage across the generator coil. Re tune the setup in other words, What I expect will happen is the output power dissipated by the resistor will increase and possibly change the efficiency somehow. It looks like you could tune it easily while loaded.

What I looked at was the efficiency of input to output. And a more lower input and faster rotor were a novelty compared to the tragic efficiency. Both loaded and unloaded as compared to a well designed and efficient "meets the load generator".

If you got 5.6 volts across the load resistor of 97 Ohms that works out to less than 0.4 of a watt. And if the input is some 3 or 4 volts at one amp when loaded then that is 3 or 4 Watts. Something to consider.

Cheers

Offline conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #754 on: January 21, 2014, 07:46:27 PM »
The thing I looked at with the speed up under load effect is the dismal output as compared to the input, overall a faster rotor is not output, the power dissipated by the load resistor is the output, and the input compared to that.

Conrad try this if you don't mind, set the arrangement to the resonance point you get at 52 Hz or whatever it is how you have it, then after connecting the load adjust the drive motor to try to increase the voltage across the generator coil. Re tune the setup in other words, What I expect will happen is the output power dissipated by the resistor will increase and possibly change the efficiency somehow. It looks like you could tune it easily while loaded.

What I looked at was the efficiency of input to output. And a more lower input and faster rotor were a novelty compared to the tragic efficiency. Both loaded and unloaded as compared to a well designed and efficient "meets the load generator".

If you got 5.6 volts across the load resistor of 97 Ohms that works out to less than 0.4 of a watt. And if the input is some 3 or 4 volts at one amp when loaded then that is 3 or 4 Watts. Something to consider.

Cheers

Attached are the scope shots for the air core test (the phase shift of the current is still similar to the mild steel core test).

Scope shot of "mild steel core test" see here http://www.overunity.com/13460/teslas-coil-for-electro-magnets/msg384149/#msg384149


@Farmhand: The coil with air core seems to have a maximum output over the 100 Ohm resistor at about 200 Hz, at 240 HZ it definitely puts out less, also below 200 Hz.

The output is very low compared to the demands of the DC motor ( ~0.3 Watt versus ~4 Watt). It is a very bad generator, but it is intended to measure the "speed up under load" and not "generator design". You are right, there are many things to consider if maximum output is the goal.


@all: General observation

My feeling is that the "speed up under load" or the "delayed Lenz effect" has something to do with "resonance of the coil with its self capacitance", which can be shown at lower frequencies with an "external parallel LC circuit capacitor of high capacitance" (such simulating the resonance condition at an artificially lowered frequency).

To spin this haphazard theory a bit further: if the generator coil is in this "resonance condition" it introduces heavy losses and the losses are reduce if a load pulls the generator coil out of the resonance condition. Therefore the "speed up under load" and the "reduced power consumption of the drive motor under load".

May be I am wrong, but my tests point in this direction.

Greetings, Conrad

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #754 on: January 21, 2014, 07:46:27 PM »
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Offline gyulasun

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #755 on: January 21, 2014, 10:51:15 PM »
...
 The coil with air core seems to have a maximum output over the 100 Ohm resistor at about 200 Hz, at 240 HZ it definitely puts out less, also below 200 Hz.
...


Hi Conrad,

When you have some time, would you make a scope shot of the voltage and current when the air core coil have the max output with the 100 Ohm load at about 200 Hz?  If the shot is very similar to what you have so far showed just in the previous post, then of course no need to make it, just mention that.  (I am interested in the phase relationship under this condition.)

EDIT: A strange thing I observe: when you have a voltage max at about 52 Hz by the scope measurement (loaded case, with bolt, series bifi, motor input 4.4V/1.68A from your video ),  the 10 uF capacitor needs 936.7 mH coil inductance to get resonance at 52 Hz.  How is it possible I wonder, the bolt makes your series bifi coil to be 520 mH.

Thanks,  Gyula

Offline MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #756 on: January 22, 2014, 12:24:03 AM »
Conrad:

What a beautiful setup you have!  I am going to be busy for a while so I can't say too much now.  I think I see the "light at the end of the tunnel" already though.  There are many tests you can make so have fun.  I can see you have a suggestion queue going also!

I have always said, when you make a change, the electromechanical impedance of the motor changes and you have to investigate that before drawing any conclusions.

Here are my first impressions:

The motor speeds up when you add the load, so that must mean the mechanical load, i,e.; the "back torque" from the coil decreases.

When I look at the coil in resonance I see the highest voltages and currents.  You know the coil resistance and the current sensing resistance and the RMS current.  So you can calculate the power dissipation in that system.  Note this is analogous to reactive power with resistive losses in the wiring.

When you add the load, you have all the resistances and RMS current.  We can see that the RMS current has dropped.  So you can calculate the power dissipation in this system.

As others have already said, it looks like the total power dissipation in the coil system goes down when you add the load. 

Therefore we can conclude that the rotor speeds up because the total power dissipation in the coil system goes down.  It's almost too obvious and it's amazing how a well run experiment can clarify things up.  With 20-20 hindsight some of these effects will seem obvious.

It would appear that an unloaded coil + capacitor at resonance is a power hog.  It makes perfect sense because the voltage and current increases at resonance, and that means you burn off more power in the coil itself.

Note of course that the belief is that it's (resonance + load) that gives you an advantage, and that is open to more investigation.  But we now know that a coil in "pure resonance"  (coil and cap but no load resistor) is actually a heavy load. (to be confirmed by someone crunching the numbers)

Anyway, that's a great start on your part.

Here is an advanced call on what we are seeing:  The "delayed Lenz effect" is really an impedance change in the coil such that it burns off less power with a load resistor added as compared to just resonating with no load resistor.  The reason many people were "thrown off the trail" is because when a (coil + cap) is in resonance alone (no load resistor) it actually acts somewhat akin to a "matched" load resistor.  i.e.; the voltage and current increase in the LC resonator to the point that the resistance in the coil wire itself becomes a nasty load on the motor.

I believe perhaps people believed that there was "almost no load" when there was no load resistor and "a bigger load" when they added a load resistor.  In fact, it was the opposite of what they thought.  It's happened before, some of these things are not obvious at all and it shows the value of "doing the experiments" with the caveat that you can't "just observe and draw up conclusions."  You have observe and then work the problem out and crunch the numbers and do A-B comparison testing and so on.

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #756 on: January 22, 2014, 12:24:03 AM »
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Offline Magluvin

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #757 on: January 22, 2014, 12:35:06 AM »
The thing I looked at with the speed up under load effect is the dismal output as compared to the input, overall a faster rotor is not output, the power dissipated by the load resistor is the output, and the input compared to that.



I think there is something with speedup under load. The question is why less load on the rotor when the pickup coil is loaded compared to unloaded? If we add another pickup coil, would the speedup not speedup so much as just 1 coil?

Romero had 16 pickups and had very good speedup. If speedup does reach the same rpm with 1 coil and more than 1 coil, then start adding coils till the output reaches or exceeds input.

Mags

Offline Farmhand

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #758 on: January 22, 2014, 01:29:21 AM »
Conrad:

What a beautiful setup you have!  I am going to be busy for a while so I can't say too much now.  I think I see the "light at the end of the tunnel" already though.  There are many tests you can make so have fun.  I can see you have a suggestion queue going also!

I have always said, when you make a change, the electromechanical impedance of the motor changes and you have to investigate that before drawing any conclusions.

Here are my first impressions:

The motor speeds up when you add the load, so that must mean the mechanical load, i,e.; the "back torque" from the coil decreases.

When I look at the coil in resonance I see the highest voltages and currents.  You know the coil resistance and the current sensing resistance and the RMS current.  So you can calculate the power dissipation in that system.  Note this is analogous to reactive power with resistive losses in the wiring.

When you add the load, you have all the resistances and RMS current.  We can see that the RMS current has dropped.  So you can calculate the power dissipation in this system.

As others have already said, it looks like the total power dissipation in the coil system goes down when you add the load. 

Therefore we can conclude that the rotor speeds up because the total power dissipation in the coil system goes down.  It's almost too obvious and it's amazing how a well run experiment can clarify things up.  With 20-20 hindsight some of these effects will seem obvious.

It would appear that an unloaded coil + capacitor at resonance is a power hog.  It makes perfect sense because the voltage and current increases at resonance, and that means you burn off more power in the coil itself.

Note of course that the belief is that it's (resonance + load) that gives you an advantage, and that is open to more investigation.  But we now know that a coil in "pure resonance"  (coil and cap but no load resistor) is actually a heavy load. (to be confirmed by someone crunching the numbers)

Anyway, that's a great start on your part.

Here is an advanced call on what we are seeing:  The "delayed Lenz effect" is really an impedance change in the coil such that it burns off less power with a load resistor added as compared to just resonating with no load resistor.  The reason many people were "thrown off the trail" is because when a (coil + cap) is in resonance alone (no load resistor) it actually acts somewhat akin to a "matched" load resistor.  i.e.; the voltage and current increase in the LC resonator to the point that the resistance in the coil wire itself becomes a nasty load on the motor.

I believe perhaps people believed that there was "almost no load" when there was no load resistor and "a bigger load" when they added a load resistor.  In fact, it was the opposite of what they thought.  It's happened before, some of these things are not obvious at all and it shows the value of "doing the experiments" with the caveat that you can't "just observe and draw up conclusions."  You have observe and then work the problem out and crunch the numbers and do A-B comparison testing and so on.

MileHigh

Well I have been saying almost that exact same thing for quite some time, mainly in the other thread, I've also said the speed up effect is an increased lenz effect that is decreased by the load, go figure. If the frequency is again adjusted then the output will increase as the resonance is "refound on load", it is something that must be done when getting power from activity in a tank, if the load drops the activity you need to readjust the circuit to get back as much of the activity as possible. Some loads can increase the activity if the system is slightly off resonance to begin with. The effect on the tank is no different to what I see in any resonant tank I load.

As I said the voltage and activity in the tank increase until it creates a significant parasitic load. Best way is to tune the circuit to the load till the proper output is gotten.

Once the maximum output on load frequency is established for that load then if the load is removed at that frequency the input will drop.  :) Is my assumption based on experience.
This is due I think to the fact that the circuit is adjusted to loaded "resonance" and when the load is removed it goes to a less than resonant condition, therefore the tank voltage and activity is less with no load and so the input is less.

We all know that a resonant tank will increase its voltage and activity to the point of loss, which is why a low loss tank is important if we use one like that.

I found I heated up 0.7 mm wire by a direct short when tuning to try to increase current under the dead short or even heavy load.

It is nice to see when a load is attached like a filament globe light right up by tuning after having it drop the activity and not light up. It shows the power of the resonance good resonance makes a hard voltage that will meet any load it can if adjusted.

..




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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #758 on: January 22, 2014, 01:29:21 AM »
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Offline Farmhand

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #759 on: January 22, 2014, 01:46:09 AM »
Here is a quick video that shows tuning the tank to the different loads and no load, the tank is excited by the transmitting transformer which is an AC generator, the tank I adjust is the output tank of the receiver coil, in this case the resonance of the transmitting and receiving coils are at play as well but are only slightly affected by the not so tightly coupled tanks. There was no tank on the transmitting coil as such, but when conducting the primary capacitance makes resonance on the primary of the transmitter, the transmitter tank is only a tank when the mosfets are conducting, not important, the effects are at the receiver. but the period can be changed at the transmitter to effect the same result. Easy, it can be tuned from either end, which shows changing the applied frequency or adjusting the L/C of the tank will re-tune the tank.

Tank tuning.
http://www.youtube.com/watch?v=jJgHWYTk6_g

This video shows the transmitter resonant waveform going to the receiver and the input drop under load ect. Same effect, same output tank style.
http://www.youtube.com/watch?v=Xcy-bGetZf0

..

I'm certain if Conrad keeps experimenting he will be able to show almost every aspect of it with different effects when tuning the setup.

Another thing to try might be to setup a "series tank" with the load in the tank already and tune to best output to see any real difference between series and parallel loaded resonance. I must admit I did not try that.  :-[ The effect would be that resonance is only attained on load and with series resonance, until the load is attached there is no tank.

..

So much for infinite impedance of a parallel tank. What it means in practice is higher input with no load not lower as many Like Duncan from EF tout.

With a solid state setup if the system is out of tune when no load but in tune when on load then the input is very small with no load (out of tune) , then when the load is added it becomes what tunes the tank and input will increase. It is all a matter of tuning for output. That's why they call them "tuned circuits" to get the most from them they must be tuned.

..

I think when loaded the inductance drops in the tank. like shorting a second coil on a regular transformer drops the inductance of another wound on the same core.

..


Offline Magluvin

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #760 on: January 22, 2014, 04:06:32 AM »
Was thinking about how to keep the 2 wires together while winding. I remembered today I saw a guy that used an empty pen to guide and feed the wires around his star coil. I think its the guy with the Dean Martin hat and has part in the pulse motor buildoffs. Anyway, I buy this Chair Repair superglue from Ace and it comes with a couple siring looking applicators that I fitted to a piece of 1/8in pvc tube. Pic shows 1 wire and it looks like 4, 5 or 6 or maybe 10 could fit. I cannot find anything smaller at the moment. Possibly if I keep the tip bent a bit, the wires will stay together better.

Another way would be to twist the pairs as I wind. Lol, even thought of how to run the wire off the 2 spools and they are mounted to a spinning wheel. I make a jig that once the wires come off the spools, they are directed back and over the spinning wheel with spools, and the winding of the wire to the new bobbin is what spins the wire wheel to twist the wires.

But twisting them would take up space on the coil.

So we will see if the capacitance is different with this coil. if not, then I have to blame it on not enough surface area of smaller wire and capacitance suffers. Would seem strange, all that density of fine copper and little air space. If thats the case then flat or square wire would be the next best bet at getting the most capacitance.

Mags

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #760 on: January 22, 2014, 04:06:32 AM »
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Offline MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #761 on: January 22, 2014, 06:14:27 AM »
Farmhand:

I looked at your clips and you may be observing some similar effects but it's hard to tell from the viewpoint of the watcher of the clip.  Your comments and observations about being on resonance vs. off resonance are correct like you stated, but real measurements with a scope and everything else make a difference.

Conrad has a great test setup.  For example, a typical experimenter connects a load resistor and the pulse motor speeds up past the resonance point and they call that the "delayed Lenz effect."  What about what happens when you connect a load resistor and you want to still measure what happens at resonance?  That's more interesting information.  With Conrad's setup he just has to lower the voltage to the DC motor and then run at the resonance frequency and make some more measurements.  This allows you to do a nice A-B comparison:  Behaviour with and without a load resistor at the resonance frequency.  Note you can still measure the DC motor power consumption.

Likewise, you have to consider the wire resistance of the coil relative to the resistance of the load resistor.  You can always measure the power dissipation in the load, or in the coil-load combination.  It's all relevant data that can't be ignored if you want to track where the power is going.

And impedance matching is the dominant factor in all of this.  With a pickup coil with a load resistance that varies between zero ohms and infinity ohms and no capacitor, we know that there is no power dissipation in the load resistor at either extreme because it is a complete impedance mismatch.  Likewise, we know that at the matched impedance you get maximum power dissipation in the load resistor (and in the coil.)  Something similar is happening when you throw the capacitor in the mix.  Resonance comes into play and tends to make the coil suck more power to burn off in one or both resistances, but clearly impedance matching is coming into play just the same.  Note even with a cap, if the load resistor is zero or infinity, you still get zero power transfer into the load.

Is there really and truly a "delayed Lenz effect?"  The answer is almost there, you just have to look for it.  It's such an easy experiment also.  You just put a tiny sensor coil on the other side of the spinning rotor magnet.  With some care and some experimentation you can find a way to use the sensor coil as a scope trigger and as a top-dead-center indicator relative to the real pickup coil.  Then you simply look at the current waveform for "no delayed Lenz" and "delayed Lenz."  You will be able to precisely determine if the pickup coil is in repulsion or attraction as the rotor magnet spins by, by carefully analysing the current waveform in the coil relative to the angular position of the rotor magnet.  You do the A-B comparison with the no-capacitor case at the same frequency.

Let's assume that you do the A-B comparison test and you find that there is a phase shift in the current waveform and the onset of Lenz repulsion or attraction is indeed delayed when you add a load resistor and the motor speeds up.  That's interesting but the real action is all about the overall impedance of the (coil + load resistor + capacitor).  It's the impedance match or lack of impedance match that determines the amount of power burned off in the real load resistor.  That determines the Lenz drag and that determines the rotor speed.  The phase angle of the current waveform in the pickup coil is related to the impedance but you still must look at everything if you really want to know what's going on.

The source impedance is somewhat abstract.  It's related to the rate of changing magnetic flux from the spinning rotor magnet interacting with the pick-up coil.  The magnet only has so much flux and likewise the motor can only output a certain amount of power.  It's how the pickup coil + load resistor + optional cap match that source impedance and draw power from it.

Conrad will do his thing and pursue his own line of investigation.  You can certainly appreciate that he has a great test bed and he is pretty much in control of most or all of the variables.  For me, it's great to see how he is really using his scope to monitor the current and the voltage in the pickup coil setup.  Modern scopes spit out live RMS voltage readings, it's almost too good to be true.

MileHigh

Offline tinman

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #762 on: January 22, 2014, 11:27:32 AM »
This reminds me of my old LAG-lenz asisted generator project's-way back then lol.
Please excuse my green understandings of days past.

https://www.youtube.com/watch?v=oKb3F61cg_s

Test data video.
https://www.youtube.com/watch?v=Tv8SGxWNELo

Offline conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #763 on: January 22, 2014, 04:52:54 PM »
Hi Conrad,

When you have some time, would you make a scope shot of the voltage and current when the air core coil have the max output with the 100 Ohm load at about 200 Hz?  If the shot is very similar to what you have so far showed just in the previous post, then of course no need to make it, just mention that.  (I am interested in the phase relationship under this condition.)

EDIT: A strange thing I observe: when you have a voltage max at about 52 Hz by the scope measurement (loaded case, with bolt, series bifi, motor input 4.4V/1.68A from your video ),  the 10 uF capacitor needs 936.7 mH coil inductance to get resonance at 52 Hz.  How is it possible I wonder, the bolt makes your series bifi coil to be 520 mH.

Thanks,  Gyula

@Gyula:

Steel core: I think that the mild steel bolt causes strange effects, e.g. that the inductance is very high at low frequencies. The inductance at 100 Hz is about 520 mH and drops fast with rising frequency, and it could well be 930 mH at 50 Hz. The steel bolt is useless and introduces too many unknown factors. For Ferrit core tests I have to wind two new identical coils (one monofilar and the other bifilar) over a 10 mm Ferrite core, what I want to do anyway soon. I can not fit my 8 mm Ferrite core into the big coil I am using now. And a 6 mm Ferrite core would rattle (that is why I did not buy it).

Air core: The big problem with the scope shots is the placement of the oscilloscope probes, specially the GND of the probes (which has to have the same potential for both probes). See the attached circuit diagram, I have changed the placement of the probes and the scope shots might look more familiar to you concerning the phase shift of current.

In the original cope shots the phase of current and Voltage was 180° shifted due to the placement of the probes and therefore it was unfamiliar for you.
Original scope shots (air core) are at: http://www.overunity.com/13460/teslas-coil-for-electro-magnets/msg384192/#msg384192

Attached please find the new scope shots with the new placement of the scope probes.


- The two top scope shots show the "speed up effect". (Voltage over the motor was not changed, only the 100 Ohm load was switched on).

- The two bottom scope shots are at higher speeds (222 Hz and 281 Hz) with the 100 Ohm load still on. The Voltage over the motor had to be increase to get to these higher speeds. You see that at 222 Hz the output was higher than at 281 Hz. Starting with 200 Hz there is no increase of the output (although the motor needs ever more Voltage and Amperage).

I will test with a variable resistor as a load next (air core).

Greetings, Conrad

Offline conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #764 on: January 22, 2014, 05:05:57 PM »
This reminds me of my old LAG-lenz asisted generator project's-way back then lol.
Please excuse my green understandings of days past.

https://www.youtube.com/watch?v=oKb3F61cg_s

Test data video.
https://www.youtube.com/watch?v=Tv8SGxWNELo

@tinman: I looked at your "LAG", very impressive. Could you please post a link to more information. At what stage is the project?

I did not try to build a new motor, I use an ordinary 12 V DC motor to spin a diametrically magnetised ring magnet. And I put a 10 µF cap in parallel with a generator coil placed in front of the spinning magnet.

The big 10 µF cap (in parallel with the generator coil) serves to simulate a generator coil with a massive self capacitance in order to bring the (faked) self resonance down to a low frequency (in this case 52 Hz). According to my opinion this allows to simulate the so called "reduced Lenz drag" or the "speed up under load" (what your LAG is doing).

Have a look at my video http://www.youtube.com/watch?v=vAXQBpuLu68 . I would be interested in your opinion, since you built a LAG.

Greetings, Conrad

 

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