Homopolar generator information

[pallidin]

Such a thing ought not to work by my understanding of how electricity is generated.

Speculating off the top of my head, however, I suppose it could be that the magnetic field has its own inertia separate from the magnet generating it. Moving the magnet would not necessarily cause an instantaneous movement of it's field. I know this is true of electric fields - there is a lag when you move a charged object between the time you move it and when it's electric field catches up to resume its former radiant configuration. That being the case, the same may be true for the magnetic field and might account for how a conducting magnet (hard steel, say) or a magnet/conductor sandwich could be made to induce current in itself. That is just a guess.

Zooby

A great speculation! Best I've heard yet. Much better than the "static magnetic field" theorists. Good job. Reminds me of the free-space field-effect I proposed on another post for something entirely different, so I do understand what you are getting at. Now, let's examine this:

- The far end of a magnetic field that is 1-foot away from the source magnet cannot move "instantaneously" with the movement of a rotating source magnet, because to do so would directly imply that a reaction is effected faster than the speed of light. So, a "lag" as you stated, is highly likely to occur. The higher the rotational speed, the greater the lag. Lag "recovery" would necessarily cause the magnetic field to cut across the conductive disk attached also 1-foot from the magnet, therefore generating current flow. Or would it?
Think about it. What's missing here?
Well, the attached conductive disk that is 1-foot away from the source magnet ALSO CANNOT FOLLOW the rotation of the source magnet "instantaneously", so it lags as well!
Ah, now we have the picture. The magnetic field lags, but the conductive disk it hopes to cut across also lags, and so that local reference frame is completely static with respect to each other, producing no induced current!

But, what if the system was such that the lags were not complimentary(and perhaps this is true even in this case) would current be produced? I would think so. But there is another problem. Once a load circuit is completed to allow the generated electron movement to produce work, a local back EMF is also produced, tending a resistance to the lag field and thus the source magnets rotation, thus requiring work to continue generation.

Interesting. This would seem to imply that such a mechanism, spun very fast, would actually slow down faster than an identical mass system without magnetic influence.
That would make for one hell of a good experiment. I think I'll have another beer and think about this. :surprise:

 

[zoobyshoe]

The thing is, when you speak of the conducting disk also lagging, there doesn't even have to be a conducting disk if the magnet itself is a conductor. This could be a hard steel magnet or an alnico one. Some ceramic magnets I have seem to conduct and others don't. [The ones that don't may simple have an enamel coating, I can't tell.]

The authors of the paper I cited report having rotated a small alnico cylindrical magnet in a lathe. They connected to the axis of rotation by means of a carbon brush held in the tailstock and to the circumference of the rotating magnet by a separate carbon brush. There was no separate conducting plate or anything. The voltage they measured increased with the speed and they measured a top voltage of about 1.5 volts. (Unfortunatly, they didn't bother to see how many amps they could draw.) They gave the dimensions of the magnet as about 1 cm diameter by 4 cm length. It was held in a plastic bushing to insulate it electrically from the chuck.

It occurred to me after I wrote my previous post that once the magnet got up to speed the "lag" would become uniform and cease to change. There would be no further relative motion between the magnet and its own field. The field might appear torqued if you could see it, but it would be unchangingly torqued, and you couldn't expect any current.

If, as you mention, the back emf opposed the "lag" field, then we might propose a kind of simple harmonic motion or resonance where the two are constantly oscillating back and forth thus continuing the relative motion between field and magnet.

Magnetic fields have electric field lines as their "raw material" so to speak, and the notion that axial rotation does not also cause a rotation of the magnetic field would mean that electric field lines can jump from one electron to another, if you see what I mean. I very much doubt that. Each electron has its own, personal electric field lines that it carries with it where ever it goes, and I don't see them being exchanged among each other.

The energy, of course, is always actually coming from the work it takes to rotate the magnet.

Zooby

 

[Binki]

Palladin / zoobyshoe

The faraday disk itself as a generator is no mistery to science, take an electrical engineering textbook to see your typical diagram of a sigle conductor passing through a magnetic field and its corresponding formula to show the relation of field strength by conductor length by speed gives you the voltage generated. The textbooks go on to the next step very rapidly expalining that you can multiply the voltage by windings. The fact is that the faraday disk exactly relates to just one conductor moving through a magnetic field (Gaus x legth x speed).

You will also find that on applying a load to the circuit you will have a breaking effect exactly proportional to the power drawn (right hand rule).

Many people (including Tesla) have mused over making a spoked wheel until they have realized that the disk is simply a single conductor moving through the field non stop.

Some of us :-) believe that the 'field could be independant' to the source when rotating axially - but as has allready been shown there is no real proof - maybe the insistance on this is due to the fact that somewhere in all this manipulation of the field there seems to be some anomalies to the standard textbook theories or are these so called anomalies just badly conducted experiments givien false results.

In any case I believe sincerely that as long as we can keep imagining new ways of using the magnetic field we can only advance and giving into "Text book science" is a defeatist attitude. Thrashing the magnetic field back and forth causing all sorts of losses through histerisis and back emf has given modern society an energy back bone in order to advance in many other fields of science, but maybe some day we could come back to the roots and generate electricity in a more harmonious way like the Earth itself is probably generating for some other unknown purpose.

 

[zoobyshoe]

Palladin / zoobyshoe

The faraday disk itself as a generator is no mistery to science, take an electrical engineering textbook to see your typical diagram of a sigle conductor passing through a magnetic field and its corresponding formula to show the relation of field strength by conductor length by speed gives you the voltage generated. The textbooks go on to the next step very rapidly expalining that you can multiply the voltage by windings. The fact is that the faraday disk exactly relates to just one conductor moving through a magnetic field (Gaus x legth x speed).

Yes, I don't think anyone here is mystified by a conventional Faraday generator. It is this matter of a rotating magnet with no conductor attached being able to generate current that is mystifying me.

You will also find that on applying a load to the circuit you will have a breaking effect exactly proportional to the power drawn (right hand rule).

Do you mean "braking" effect? As in it slows it down? Or "breaking" meaning the circuit is shorted?

As far as I know the "right hand rule" is an outdated version of the "left hand rule", the revision having occurred when it was realized that electrons flow rom the negative terminal tothe positive, and not the other way around as was previously thought. Its purpose is to determine the direction of the lines of force around a conductor, or to determine the polarity of a solenoid from the direction in which the current is flowing. It doesn't seem to have anything to do with effects following a load on a generator.
Am I missing something?

Many people (including Tesla) have mused over making a spoked wheel until they have realized that the disk is simply a single conductor moving through the field non stop.

I believe the purpose of the spokes is to selectively diminish the area in which current is being generated in order to diminish the eddy currents. Tesla's design additionally configured the spokes as involute curves.

Some of us :-) believe that the 'field could be independant' to the source when rotating axially - but as has allready been shown there is no real proof - maybe the insistance on this is due to the fact that somewhere in all this manipulation of the field there seems to be some anomalies to the standard textbook theories or are these so called anomalies just badly conducted experiments givien false results.

Yes, in addition to the links by jdo300 I have come across other people who maintain the field doesn't rotate axially. I don't find that to be a persuasive explanation of the effects.

In any case I believe sincerely that as long as we can keep imagining new ways of using the magnetic field we can only advance and giving into "Text book science" is a defeatist attitude. Thrashing the magnetic field back and forth causing all sorts of losses through histerisis and back emf has given modern society an energy back bone in order to advance in many other fields of science, but maybe some day we could come back to the roots and generate electricity in a more harmonious way like the Earth itself is probably generating for some other unknown purpose.

Models are never complete and are usually subject to revision. The Earth's magnetic field is not understood, and there are many researchers trying to find a good model for how it may be generated. I wouldn't jump to the conclusion that it is being generated in a particularly harmonious way. It is known to be quite unstable, as you're probably aware, constantly shifting position and subject to periodic reversals in polarity. That, however, is a subject for the Geology forum.

 

[zoobyshoe]

Experimental Results

O.k. everyone.

I located a small cylindrical conducting magnet and recreated the set up reported in the paper I read. I found one measuring .510 diameter x .592 length. I am not sure what material the magnet is, but it is either hard steel or alnico. It is not ceramic. It had a resistance of about 2 ohms when I placed the leads one on the axis of rotation and the other on the circumference, to check that it was a conductor.

I chucked it into my little bench lathe insulating it from the jaws with plastic and made contact with the circumference with an electrical brush taken out of an electric mixer motor. The brush was also insulated from the toolholder by shims of plastic, top and bottom. I made contact with the axis of rotation by chucking a pencil into the tailstock and touching it up against the magnet. I cut the wood away from the pencil down to the carbon about an inch back from the tip to have a place to touch the meter leads.I checked for continuity with an ohmmeter both before and during spinning of the magnet and there was always continuity.

There was, however, no voltage and no amperage during spinning.

I checked at several increasingly faster speeds, checking the continuity each time. There wasn't the slightest little jiggle of the needle when I set it on dc volts or dc amps.

As far as I'm concerned, a rotating conducting magnet does not generate any current in the absence of a stationary conductor.

I can't account for the results reported in the paper I read, but I no longer believe what was reported is accurate.

 

[zoobyshoe]

Pallidin: take two ring magnet place them on both sides of a conducting disc and rotate them all together, you wil have a charge between axis and perimeter. You would not see a charge if the field was rotating with the disc. Binki

I want to try this one next. When you say "ring" magnet, will the annular magnets from a common audio speaker suffice?

You say to put one on each side of the conductor. They are concentric with the axis of rotation, correct? Also, you mean with unlike poles facing each other so there is attraction between the magnets through the conducting disk, correct?

And you are saying that if I rotate them all together, magnets and disk, at the same time at the same rate I will be able to take current off by connecting to the axis of rotation and to the periphery of the conducting disk?

-Zooby

 

[Binki]

Do you mean "braking" effect? As in it slows it down? Or "breaking" meaning the circuit is shorted?

Yes, braking/slowing down, the same way any generator when free running (ie no load) draws less power from the driving source than when it is loaded.(Please excuse my spelling)

As far as I know the "right hand rule" is an outdated version of the "left hand rule".

Right hand, Left hand - I'm not trying to rewrite textbooks and for the sake of simplicity I have simply stated something that we all should understand.

I believe the purpose of the spokes is to selectively diminish the area in which current is being generated in order to diminish the eddy currents. Tesla's design additionally configured the spokes as involute curves.

If you have the same intensity of magentic field over the surface of the disk, there are no eddy currents, the electrons are pushed all in the same direction (from or to the axis) and there is no return path other than an external circuit. This is what causes a lot of confusion.

What I was trying to show on my last post was that a conductor in a magnetic field either a wire or a disc will stand up to the standard generator/motor formulas. I know it, I've Done it.

I must also add on zooby's experiment that you will need a reasonably powerfull magnet to get any effect, some rare Earth magnets get up to 10,000 Gauss aprox but iron based magnets are very weak. Also the larger the diameter gives you logically more conductor length and therefore a higher voltage with the obvious mechanical problems of a higher speed peripheral for your sliding contact or brushes.(Maybe I'm just stating the obvious to all you guys out there! )

 

[zoobyshoe]

Yes, braking/slowing down, the same way any generator when free running (ie no load) draws less power from the driving source than when it is loaded.(Please excuse my spelling)

Thanks for clarifying. The point is now understood.

Right hand, Left hand - I'm not trying to rewrite textbooks and for the sake of simplicity I have simply stated something that we all should understand.

Either way, I think the actual concept you wanted was Lenz's law not a hand rule. Lenz's law states that "induced current always flows such that its magnetic field opposes any change in the original magnetic field that induced it." This "opposition" is why it is harder to turn a generator under load. The left hand rule can be used in conjunction with Lenz's law to find out what direction current flows, or what polarity the fields have, but Lenz's law and the left hand rule are two distinct things and aren't interchangable.

If you have the same intensity of magentic field over the surface of the disk, there are no eddy currents, the electrons are pushed all in the same direction (from or to the axis) and there is no return path other than an external circuit. This is what causes a lot of confusion.

Yes, I see your point here. The "spoked" generators, Tesla's included, are not designed for uniform fields over the whole disk. Like Faraday's original generator, the magnetic field is applied in one place.

What I was trying to show on my last post was that a conductor in a magnetic field either a wire or a disc will stand up to the standard generator/motor formulas. I know it, I've Done it.

I think everyone is OK with this.

I must also add on zooby's experiment that you will need a reasonably powerfull magnet to get any effect, some rare Earth magnets get up to 10,000 Gauss aprox but iron based magnets are very weak. Also the larger the diameter gives you logically more conductor length and therefore a higher voltage with the obvious mechanical problems of a higher speed peripheral for your sliding contact or brushes.

The magnet I used was reasonably powerful for its size but was a pretty small magnet. If a more powerful magnet is needed to get any current I would tend to side with Palladin in his suggestion that the current you may see is simply what is being induced in the conducting material of the brushes.

I tried the configuration you mentioned of two magnets on each side of a conducting disk all rotated together. I used two speaker magnets on opposite sides of an aluminum disk.
The magnets are 2.937 inches in diameter x .404 thick. The disk is 3.414 diameter x .025 thick.

I glued both magnets to the aluminum with superglue but wasn't able to get them perfectly concentric with each other. One was about .005 eccentric. This made the lathe vibrate a little when I spun them, and I never dared to crank it up to full speed. I got up to about 1500 RPMs and didn't dare go higher.

Anyway, with this configuration, I did, in fact, get the tiniest little voltage and current. The needle on the meter moved enough that I was sure it had actually moved and I was sure it was actually dropping back to zero when I removed the leads from the circuit. It looks to have generated one or two millivolts.

It rose half a hair higher when I doubled the speed.

I really think all that was happening is that I was inducing a miniscule current in the brush that was in contact with the circumference of the disk, and expending quite a lot of watts to do it.

Zooby

 

[Binki]

Maybe its time to explain a little about on of the experiments I was involved in. (There being some interest in the subject )

The machine set up was to clear up some initial doubts on the faraday generator/motor effect and was built to completely enclose the magnetic field to eliminate any claims of induction in the external circuit. the field was created by copper coils calculated and tested to give 1.6-1.8 Tesla (16000-18000 Gauss) which was the saturation of the iron we were using. The core was made of two F/disks of 8 inches diameter mounted on a hardened copper shaft with a copper slip ring silver soldered to its perimeter. The disk was part of or centre of the main magnetic keep that enclosed the coils leaving only a 5mm gap through which a copper plate passed in order to extract the current and also a base to hold the coils and brushes. You can imagine the shape as something like two dinner plates cupped together. there were two units on the same shaft in order to double the voltage generated. The brushes were made of 95% silver/carbon (No expense spared) so the no load consumption of the DC motor was only 200 watts approx. Even after all this the machine only produced the calculated 5.6 Volts at 3000 rpm and 3000 Amps approx.

An almost identically sized faraday disk Motor would turn proportional to the intensity of the magnetic field etc.

One of the fascinating features of this set-up was to see the motor side turn at any speed (from almost standstill to the equivalent speed of the generator) adjusted by the field strength, with a torque equivalent to the Watts involved. That is even at 1 rpm the turning power was there you could hold on to the shaft and it was humanly impossible to stop by hand.

If you capture the set-up from my basic explanation you may appreciate that the generated current could have been produced in the core/centre or in the gap through which the copper plate passed in order to extract the current, which of course does not prove or disprove movement of the field.

After all this experiment gave me a very clear view of the concept and did not give any inclination towards OU.

The use of coils maybe give an easier comprehension of the field being independant to the source but does not prove rotation or non rotation of the field.

 

[zoobyshoe]

The machine set up was to clear up some initial doubts on the faraday generator/motor effect and was built to completely enclose the magnetic field to eliminate any claims of induction in the external circuit.

I have questions about this that I'll ask later because they are less important to me than others I have.

the field was created by copper coils calculated and tested to give 1.6-1.8 Tesla (16000-18000 Gauss) which was the saturation of the iron we were using.

Very strong magnets.

The core was made of two F/disks of 8 inches diameter mounted on a hardened copper shaft with a copper slip ring silver soldered to its perimeter. The disk was part of or centre of the main magnetic keep that enclosed the coils leaving only a 5mm gap through which a copper plate passed in order to extract the current and also a base to hold the coils and brushes.

This I don't understand. The disks were copper. How could they form part of a magnetic circuit? You cannot put a piece of copper across the pole of a horseshoe magnet and form a magnetic circuit. A "keeper" must be of a material in which a magnetic field can be induced by proximity to another magnetic field.

I'm also not understanding the 5mm gap. Perhaps because I'm not sure of the orientation of the electromagnets with regard to the disks. You spoke earlier of a "uniform magnetic field". What that says to me is that on one side of the copper disks you have a north pole pointed at the disks which completely covers the whole area of that side of the disk. On the other side you have a south pole that completely covers the whole area of that side of the disk. There is attraction between the magnets and the magnetic lines of force go directly through the copper disks. Is this how you had it set up?

You can imagine the shape as something like two dinner plates cupped together.

And there was nothing in the space between the "dinner plates, correct?

there were two units on the same shaft in order to double the voltage generated. The brushes were made of 95% silver/carbon (No expense spared) so the no load consumption of the DC motor was only 200 watts approx. Even after all this the machine only produced the calculated 5.6 Volts at 3000 rpm and 3000 Amps approx.

Here, now, is something I find very problematic. 5.6 volts times 3000 amps makes 16,800 watts. You say you're putting roughly 200 watts into the driving motor, and so the rest must be going into the electromagnets. The trouble is that since it is a static magnetic field there is no reason you couldn't replace the electromagnets with permanent magnets of the same strength and apparently harvest the same 16,800 watts with only a 200 watt imput.

I understand this wasn't the focus of your experiment, but you can see that you are proposing something that inadvertantly becomes a case for "Free Energy".

One of the fascinating features of this set-up was to see the motor side turn at any speed (from almost standstill to the equivalent speed of the generator) adjusted by the field strength, with a torque equivalent to the Watts involved. That is even at 1 rpm the turning power was there you could hold on to the shaft and it was humanly impossible to stop by hand.

What do you mean "the motor side"? Thus far, all you have mentioned is a generator.

If you capture the set-up from my basic explanation you may appreciate that the generated current could have been produced in the core/centre or in the gap through which the copper plate passed in order to extract the current, which of course does not prove or disprove movement of the field.

In view of these other claims about rotating the conductor and magnet together and still generating current, what I need you to make clear is whether or not your electromagnets were fixed to the disks and rotating with them, or whether the conducting disks, alone, rotated.

After all this experiment gave me a very clear view of the concept and did not give any inclination towards OU.

I'm not exactly sure what the concept of OU means or implies, but if the claim is that you're getting more energy out than you had to put in, then your set up seems to have that capability were you to replace the electromagnets with permanent magnets of the same strength. That ought not to be possible, and I don't suppose it is. I hope you can understand the problem I am percieving with getting 16,800 watts out of a device that is essentially only drawing about 200 watts to operate.

The use of coils maybe give an easier comprehension of the field being independant to the source but does not prove rotation or non rotation of the field.

Which brings us back to your other claim about gluing two magnets to a conductor and rotating the whole sandwich together and being able to take current off of it. I think I will try rotating the magnets, one on each side of the conductor, opposite poles, and holding the conductor still. If I get an appreciable amount of current from the conductor it should demonstrate that the magnetic field rotates with the magnets. Does that sound right?

 

[Binki]

Zooby

The whole rotor was soft iron including what is conceptually the "faraday disk" then in order to get a good contact to the circumference of the disk a copper slip ring was silver soldered to it and then the shaft between the two assemblies was also hardened copper in order to offer the lowest possible resistance to the current.

Take the analogy of an apple having been eaten in a way that the waist or thinner part is the generating disk and the upper and lower stubs which have a greater diameter are such as to almost touch each other creating a kind of cavity. Now imagine squashing this apple down to the shape I described of two dinner plates cupped together with its core still in tact, all soft iron. Through the gap passes the copper plate that doubles as a support for the coils and brushes inside the cavity and also is the conductor extracting the current. The total diameter of the rotors was approx 15-16 Inches

Here, now, is something I find very problematic. 5.6 volts times 3000 amps makes 16,800 watts.

No, remember I said this 200 Watts was under a “NO LOAD” Situation just the friction of the brushes( Sorry no Over Unity) and the 16,800 Watts was the machine fully loaded (By the way, no permanent magnets have this strength of magnetic field- another reason to use coils was to take everything to as higher limits as possible in order to overcome any thresholds that might be involved and achieve the most accurate data possible).

In view of these other claims about rotating the conductor and magnet together and still generating current, what I need you to make clear is whether or not your electromagnets were fixed to the disks and rotating with them, or whether the conducting disks, alone, rotated.

The coils where stationary on the copper platform inside the cavity(of the magnetic keep) this copper plate passed through the 5mm gap, which could as I have mentioned have been the generating area but either way the generation of current was produced by only one side of the system by a stationary field or by a rotating field because as you may now have captured through my analogy to a half eaten apple the conductor that draws the current passes through the return path of the magnetic field (5mm gap). If the generation was to occur on both sides then I would have had a big fat Zero result.

I'm not exactly sure what the concept of OU means or implies.

OU = Over Unity (Sorry someone had already used the abbreviation and I thought that it was clear)

but if the claim is that you're getting more energy out than you had to put in, then your set up seems to have that capability were you to replace the electromagnets with permanent magnets of the same strength.

No I didn’t state the power used by the coils and if I remember correctly it was 200-300 Watts, but this was not an issue to address in this experiment we needed to go as far as possible with the field strength which was eventually limited by the saturation point of the iron we were using. some silicon irons and other alloys can reach 22,000 gaus or more before saturation.

Which brings us back to your other claim about gluing two magnets to a conductor and rotating the whole sandwich together and being able to take current off of it. I think I will try rotating the magnets, one on each side of the conductor, opposite poles, and holding the conductor still. If I get an appreciable amount of current from the conductor it should demonstrate that the magnetic field rotates with the magnets. Does that sound right?

Once again as I have already said on the experiment the generating part could be in the core ie the faraday disk or in the gap where the conductor passed this could only have been in one of the two areas as the generated voltage was exactly as the formula suggested it would be for the area of the disk multiplied by the rpm’s and by the gauss(and then by another figure that I can't remember exactly).

Your test is well worth doing and I would be interested in knowing the results. I would like to add that on discussing with a manufacturer of permanent magnets some years ago that the field is not always even over the whole surface (this was another reason for us to use a coil) and may produce some ripple’s of current and therefore the experiment might not give a true result. Mankind’s constant battle in all kinds of research is to avoid ambiguity in experimental results by making sure that the conditions of the experiment don’t give us a false result.

Some have stated in the past that if the field rotates or not has no meaning. But I feel that we not ignore any of the possibilities as we conduct our experiments.

 

[zoobyshoe]

Binki,

Unfortunately, I am more confused than ever about how your device was configured.

However, the important point is clear: that when you were drawing 3000 amps from it, the driving motor was drawing a correspondingly higher amount of power. When you were getting 16,800 watts from the generator, the driving motor was drawing even more than 16,800 watts to run the device. It is important to point this out for Cala and others who are prone to believe the stories of getting more energy out than is consumed. An electrical generator does not create energy out of nothing. It converts one form of energy to another, always with less than perfect results. We want 100% electricity out, but, instead, some of the imput always gets converted to heat and sound, among other things, and we end up with a few different forms of energy, only one of which is of direct use to us.

I went to work yesterday putting together the configuration I suggested: stationary conductor with rotating magnets.

The conductor is a thick, upright, square aluminum plate. I drilled a hole in the center of the square and pressfit a .5 inch aluminum shaft into it. This sticks out on both sides about 3 inches.This will serve both as the axle for the rotating magnets and as one of the potential power take off points. According to what you said earlier about a uniform field over the whole area of induction, I can take power off any point on the edge of the flat, upright conductor, because it should be the same everywhere.

I machined two Aluminum flanges to hold the magnets. These are essentially pulleys with magnets attached. The pulleys go onto the axle that goes through the conductor with the magnets facing each other through the conductor: north facing south. The attraction of the magnets for each other holds them rght up to the conducting plate. When I machined the pulley/flanges I left a small ring standing proud of the face of the magnets around the hole through which the axle goes to prevent the magnets from contacting the conductor over their whole face. They are prevented from getting closer than .010 to the conducting plate. Friction is limited to the area of contact with this small ring of material. Even so, I found there was a lot of friction due to the strength of the attraction of the magnets for each other. I greased the axle, which improved things.

I cannot make any direct mechanical connection between the magnets so that they rotate together. If I did, it would prevent making an electrical connection to the conducting plate. Therefore, the magnets have to be driven by belts that are going to be driven by to pulleys on a separate shaft.

At first, I hoped that I could just drive one magnet and the other would be dragged along by the magnetic field of the rotating one. However, this doesn't happen. Rotating one magnet has no effect on the other. This may mean the field doesn't rotate or it may mean it does rotate but there is too much friction for the second magnet to freewheel along with the first. It might also mean that, even if the field is rotating, it simply changes its orientation to the other magnet without any sort of angular pull arising.

Today, I will work on the driving pulleys and the shaft for them. I'm am debating about what belts to use and haven't decided, therefore, on the dimensions of the pulleys. The belts I have are too large or too small.

The way I see it, if the field does not rotate, any current that might arise from imperfections in the uniformity of the magnetic field would only generate some miserably insignifigant spikes. If the field does rotate, it should generate a clear and unambiguous high current.

If rotating the magnets generates no current, I will reconfigure to hold the magnets still, and rotate the conductor.

I have actually always wanted to try this idea of rotating the magnets and keeping the conductor stationary, because if it worked it would eliminate the brush problem everyone always encounters.

If this doesn't work, another thing I will try is rotating magnets with an asymetrical magnetic field with a stationary conductor. North-South on one side of the conductor, and South-North on the other side. In truth, I think this latter is the only configuration that has any possibility of generating any current, but I will try the others to be sure.

Zooby

 

[Binki]

Binki,

However, the important point is clear: that when you were drawing 3000 amps from it, the driving motor was drawing a correspondingly higher amount of power. When you were getting 16,800 watts from the generator, the driving motor was drawing even more than 16,800 watts to run the device. Zooby

Very little more it was very close to the 100%, I can't recall the exact value. This is what has made me ponder over how to achieve a situation to multiply the voltage by some kind of winding. I believe that I have found a way to do it but I will need time and finance to test the idea

Binki

 

[zoobyshoe]

Very little more it was very close to the 100%, I can't recall the exact value. This is what has made me ponder over how to achieve a situation to multiply the voltage by some kind of winding. I believe that I have found a way to do it but I will need time and finance to test the idea

Binki

I was just reading today about motors and it seems the higher the voltage the more losses: higher voltage means more turns of wire which ends up increasing the general resistance, which create more losses. The low voltage of your machine could be the very reason it was so efficient.

The low voltage high current output makes it good, as is, for anything that needs that to begin with. This would be an excellent generator for dissociating water into hydrogen and oxygen, probably for large plating operations such as when they purify copper, and for making hydrogen, chlorine, and sodium hypochlorite. All that large scale electrochemical stuff.

 

[Binki]

Zooby

Yes agreed, but Resistance is its main problem at 3000 Amps you can only take that sort of power a few meters distance, even with 300mm squared conductors that we used 7 meters of conductor reduced the voltage by half. If you change the ratio voltage to amps you can do more with it (i.e. the national grid is working at thousands of volts in order to reduce losses, the American 110V network needs heavier conductors and more frequent knock down transformers than the 220-240V systems in Europe). I have seen through these experiments that resistance is our ally not our enemy, electronics would simply not work without resistance, electrical systems need a resistive load or you will have a short circuit etc. There must be a happy medium between voltage and amperage.

This system is already used for many applications like a ships propeller drive therefore eliminating mechanical clutches etc but also needs super conductors with their expensive cooling etc. and also many other uses some of which you have mentioned.

Binki

 

[zoobyshoe]

Binki,

Would the voltage/amperage ratio be closer together if you used a less powerful magnetic field? Or would that cause a drop in voltage as well?

 

[zoobyshoe]

Another solution to the voltage vs amperage problem occurred to me today, Binki. Since you doubled the voltage in your machine by using two disks it should be possible to take that very much farther. You could construct the conducting rotor as a sandwich of many very thin layers of conducting metal separated by thin layers of anything non-conducting. Aluminum foil is about .0005 inches thick and most metal is available in thin sheets or rolls from .001 on up. Using the cheapest and thinnest, aluminum foil, you could fit 125 layers in a mere eighth inch with a comparably thin insulation between them. 125 x 3 volts per layer = 375 volts right from the starting gate. I don't believe the amperage could be very high from such thin conductors.

Does this make any sense given what you know from your experience?

-Zooby

P.S. I am still curious about how the magnetic field was oriented in your machine. You haven't explained the orientation of the poles yet.

 

[Binki]

Zooby

Dont forget that in order to get two disks mounted on the same shaft each had to be completely contained in opositely oriented fields because they were rotating in the same direction. This is more complicated than it seems, I will try to send a diagram.

Binki

 

[Binki]

Zooby

Voltage is directly related to flux density.

Here is a very quick sketch, it is not very neat but maybe you will get the drift from this sectional view. The two units are magnetically independant which is the only way to put them in series and double the voltage.

As to you other comment on the current drawn fron a thin conductor: The current is only limited by the load capacity of the conductor before losses i.e. copper has a limit before heating of 3000 Amps per square inch of conductor. If you were able to draw more current than the capabilities of the conductor you obviously reach a meltdown point.

Binki

 

[zoobyshoe]

Thanks for the sketch, Binki. Your machine is much more complex than I thought, and I still don't quite understand how it worked, but I'm more clear on the setup.

You say the voltage is tied to the flux density. In a normal generator voltage is tied both to the number of turns and the speed of rotation. What does faster rotation do in the homopolar dynamo? Increase the amps?

 

[Binki]

Zooby

Revise a little bit the calculation for generating a VOLTAGE: Speed, Field strength, Conductor Length.

Speed relates to only one conductor on the faraday disk as oposed to being multiplied by the number of turns in a conventional generator.

Field strength (Gauss) is the same for both systems - although optimizing is recomended in the farady disk for the above reason.

Conductor Length is the radius of the disk (within the field) whereas in the conventional generator this is multiplied by the turns.

Amperage can be drawn from both systems up to the limits of the conductors (Before they burst/burn out. Lower resistive load=Higher Amperage drawn.

 

[Binki]

Zooby

From the textbooks

Voltage=number of lines of force cut per second divided by 100,000,000

Binki

 

[zoobyshoe]

Thanks, Binki, that makes sence.

My impression from your sketch is that the coils created a pole over the whole area of each side of the disks, all north on one side and all south on the other side of the disk. Is that how it was?

I'm still working on that other test. Something blew in my lathe motor controls and I have been playing with ways to make a new control system. Figured it out tonight and will put the lathe back together tomorrow. (It's almost one A.M. here.)

Zooby

 

[Binki]

My impression from your sketch is that the coils created a pole over the whole area of each side of the disks, all north on one side and all south on the other side of the disk. Is that how it was?
Zooby

Yes, but don't forget that the faraday disk was also iron like the rest of the magnetic circuit, the only gap in the magnetic circuit was the famous 5mm gap all the rest was iron, so you get a perfectly even magnetic field.

Binki

 

[zoobyshoe]

Oh. I didn't catch that about the disk being iron before. That certainly complicates what was going on.

Do you think that in a conventional Faraday generator, which has the magnetic field in just one spot, like Faraday had, would work with my notion of the sandwich of thin conductors to multiply the voltage?

 

[Binki]

Zooby

Here's a fresh and better diagram of just one side of a rotor

Binki

 

[Binki]

Oh. I didn't catch that about the disk being iron before. That certainly complicates what was going on.

Do you think that in a conventional Faraday generator, which has the magnetic field in just one spot, like Faraday had, would work with my notion of the sandwich of thin conductors to multiply the voltage?

Zooby

the disk being iron or any other conducting material is not imortant, if we had placed a copper disk in the centre we would have had to increase substantially the field windings in order to keep the field strength at a maximum.

About your sandwich idea, remember you will achieve oposite charges between axis and outer edge of the disk, you can only invert this direction by inverting the field and then you can place each disk series with each other like a pack of batteries +-+-+- and the only way you can invert the field without influencing each other is to isolate each unit magnetically, which is what I did in my experiment but two disks is allready mechanically cumbersome.

Binki

 

[zoobyshoe]

Yes, I understand the problem now. Each layer of my sandwich will have its own voltage, but they will simply combine in parallel, and the total voltage will be only be equal to that in anyone layer, not more. Thanks for saving me the trouble of testing that idea.

What do you expect would happen if I rotated the magnets if each magnet had both a North and South pole facing the opposit pole through the conductor? Do you think it would produce alternating current? Or would everything just cancel out and produce no current?

 

[zoobyshoe]

Here's a fresh and better diagram of just one side of a rotor

I'm still completely confused. Why are the brushes on the inside? I also have no idea about what elements were rotating and which were stationary. The plate sticking through the gap is labeled as copper. I though you said it was iron? Totally confused. Sorry.

 

[zoobyshoe]

My lathe is now running again (though not as well as it used to) and today I machined the four pulleys. I also turned the ends of the drive shaft down to fit into the ball bearings in which they will run. Tomorrow I need to make supports for the bearings and then get everything mounted together on a board. I plan to simply chuck the driveshaft into an electric drill to power the thing for the test. If all goes well I should be able to see if I can get any current out of it tomorrow.

 

[Binki]

I'm still completely confused. Why are the brushes on the inside? I also have no idea about what elements were rotating and which were stationary. The plate sticking through the gap is labeled as copper. I though you said it was iron? Totally confused. Sorry.

I have explained all this before, but in order to make it clearer:

The copper conductor is the support for the coils and the brushes and it is stationary(the coils and brushes also).

The brushes draw current from the edge of the (so-called)F/Disk but you are seeing also is the iron keep surrounding the brushes and coils giving the whole rotating assembly a much larger aspect. The iron keep is essential in order to give a return path for the field and therefore maintain the field strength. The whole iron keep rotates(because it is part of the f/Disk), therefore it is necessary to have a gap in order to pass out the current. As I have already stated I cannot prove that the generation of current is in the f/Disk or in the gap, this depends on whether the field rotates or not!

Binki

 

[zega]

Here i will attach a picture of my experiment with homopolar generator...
I have NdFeB magnet 7cm diametar and 1cm thickness, field is around 0.4Tesla at the edge little bit lower at center, it is zinc coated, that zinc i used as conductor...
In this setup i spun a magnet that holds itself on fan steel cup rotor, RPM is around 1500...
Voltage i get from it range from 50-100mv depending on speed (how mutch i press the copper wire contact, rotor slows down, voltage drops) oscilloscope input is straight (no probe) terminated with 50ohm terminator to avoid static, and spikes on waweform are there on purpose to avoid confusion regarding people that don't believe that voltage is available from this setup (so they cannot claim that i just rise a line on scope via zero/offset knob on scope), so i pressed wire contacts little bit lighter for you to see both zero and max voltage because of weak contact, if i use proper force to obtain good contact line becomes solid...
Here is a pic...
ZEGA

 

[zoobyshoe]

OK, I finally understand. It is quite a bit more complicated than you realize. No doubt you are used to it, but it is nothing like any other homopolar generator I have read about.

I can see how it is so difficult to tell if the field is rotating or not.

 

[zoobyshoe]

zega,

Did you check for how much amperage seemed to be available from it?

Yours is like my second set up: magnet + conductor, in which I did manage to get a very tiny voltage and current. You got much more. I have no way to measure the strength of the magnet I used, but yours is probably stronger. My magnet was slightly larger in dia. : 7.459 cm.

Question: what is the material of the brushes you are using to make contact with the rotating magnet?

Edit: I see you already mentioned that "copper wire contacts". This is one difference. I used carbon brushes.

So let me ask what the orientation of the magnetic field is on the magnet? Is this magnet from an audio speaker?

 

[zega]

I have tried to shunt it with 0.1ohm and manage to get around 1/3 of the no shunt voltage, that is around 0.2 amps...
Limiting factor was thin wires, thin zinc coating, and overall high internal resistance of the system (it is all known in electrical engineering).
Magnet is full disc (as you can see) custom fabricated in China for me, i bought a big bunch of Neodymium magnets in china for some stuff and added this round magnets for experimenting...
It is very strong, i have borrowed gaussmetar and measured them, and i constructed and made my own gaussmetar with quad OP and hall from VCR, some magnets i got can pull 500KG (around 1000lbs) dimensions 10cmx3cmx1.5cm orientation trough 10x3 thickness and magnets are VERY dangerous...
These round magnet i oriented trough thickness (1cm) as you can see in experiment via contact placement and waweform...
All in all i plan to make two faraday generators combo in one that has edges rubbing each other at 20000RPM-s and brushes at the centers to minimise power loss due to the friction...
In center there is no high angular velocity so frictional power loss is mutch mutch reduced...
Even then if i manage to get 1-2 Volts i do not expect to run full circle because it is not that efficient...
If there is OU effect in this device i count for at least 5V out and high current (around KA) capability that can be used to close a loop...
But that kind a device is very expensive and i cannot afford it...
I plan to use this small device to test it to the power increase regarding no current drawn spinning condition, and increase in mechanical load when i increase loading of the device, to see if there is a proportional ratios, if there are no proportional ratios i will then consider making larger device to satisfy my curiosity and maybe something else...
ZEGA