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  • Mario
    replied
    Originally posted by Turion View Post
    Uh, yeah. I just gave THREE examples of coils that speed up under load in my last post.



    That is exactly the purpose of all my testing. With the size magnets and size rotor I have, and at a given RPM of 1850, what is the best coil that will produce the most energy for my setup with the LEAST amp draw on the motor. That is what I am working on, so that when folks put together the:
    1. Rewound pulse motor design of Matt's
    2. Run circuit schematic to recover better than 80% of what is used to run the motor
    3. Generator design specs
    4. Flywheel specs
    Folks have enough information to replicate and get a machine that easily produces more than it takes to run. I have already posted ALL of that information, but we are constantly improving it. Even a two coil build IS COP>1 with iron cores. Not necessarily with air cores yet, which is what I am working on.

    Dave
    Dave, sorry. I misread and didn't realise the three examples were about air cores… Well, this means I'll have to investigate further.
    I was kind of surprised of how many amps would flow through a small shorted air coil I used for testing..


    @Erfinder

    I can't quantify how much power yet. First I want to be able to test an AIR coil that speeds up under load or when shorted… or at least doesn't slow down.

    Mario

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  • Turion
    replied
    Originally posted by Mario View Post
    Hi Dave, thanks for all the input. I haven't been able to see speed up with air core coils, have you?
    Uh, yeah. I just gave THREE examples of coils that speed up under load in my last post.

    That is exactly the purpose of all my testing. With the size magnets and size rotor I have, and at a given RPM of 1850, what is the best coil that will produce the most energy for my setup with the LEAST amp draw on the motor. That is what I am working on, so that when folks put together the:
    1. Rewound pulse motor design of Matt's
    2. Run circuit schematic to recover better than 80% of what is used to run the motor
    3. Generator design specs
    4. Flywheel specs
    Folks have enough information to replicate and get a machine that easily produces more than it takes to run. I have already posted ALL of that information, but we are constantly improving it. Even a two coil build IS COP>1 with iron cores. Not necessarily with air cores yet, which is what I am working on.

    Dave

    Leave a comment:


  • erfinder
    replied
    If possible......could you "quantify" "a good output..."

    Regards

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  • Mario
    replied

    Leave a comment:


  • Turion
    replied
    That plastic used to make the rotors is called Delrin. Sorry. I had the name wrong. 3 12x12 pieces of it, and 12" of that round stock to cut two more spacers out of was $130.00 without any of the machinist's costs, so building the coil stand is not a cheap enterprise. The rotors that are on there now had 2" holes cut in them for 2" magnets and I had to have two NEW sets of rotors made with MM smaller holes that the magnets were pressed into and the iron cores STILL sucked the magnets out of the plastic. I went through three sets at $60 worth of materials a pop before I FINALLY have a set of rotors on my big generator that the magnets are staying put in, so I have lots of spare rotors around here for test bed setups to do different things with. As long as I use a crap load of ugly epoxy to hold the magnets in place, and spend the time to re-balance them.

    I am having two iron/steel rotors made to back those plastic rotors to see the effect on the flux path. They won't be ready until next week sometime, so I am on hold until then with my coil testing. I will say that Matt and I have tested a few things that dramatically change the output of the coils we have been experimenting with. I have three sizes of coil I am working with.

    My original coil was 3 strands of #23, 800 feet long, and it produced 130 volts at just under one amp per coil at 1850 RPM run by the razor scooter motor with an iron core in the coil. And it would speed up under load. But 12 coils like that was too much magnetic lock for the little Razor scooter motor to overcome, forcing us to build a complicated circuit which ran the generator as a motor until it got up to speed and the razor scooter motor could take over. This was overly complicated, so I became interested in air cores, and have since removed all the welding rods from the 12 coils on my big generator in favor of air core coils that I allow me to easily spin the three rotors with the razor scooter motor.

    To figure out what was the best coil to be used on the big generator I decided I needed to do some testing. I made a video of the output of the existing coil, but forgot to measure the amp output on the video. I believe it was something like .71 or .72 amps. Not nearly what I hoped, but about 25 watts per coil under a small load. Video here: https://www.youtube.com/watch?v=PCfmkQ0_zBk

    I had a single rotor test setup that I could place a coil next to and see the amp and voltage draw of the motor and the amp and voltage output of the coil under a small load. I tested several coils with a simple bulb attached as a load and only ONE coil out of all the ones in my box would speed up under load. As it happens, this coil had 10 strands of #23 which were each 80 feet in length, so exactly 1/3 of what was on the coils on my big generator and it would ALSO speed up under load. So, I doubled the length of the strands. I now have a medium sized coil that has 10 strands of 160 feet or 1600 feet of #23. This is 2/3 the size of my original coil, and it ALSO speeds up under load. I put this on a longer bobbin so that the area exposed to the magnet was the same size as the smaller coil, and I intend to test output of all three coils on the coil test rig when it is completed next week, along with an original coil. I also plan to rewind the medium coil on a shorter fatter bobbin and see if that makes an output difference. (Same air core size, just more turns on a shorter coil.)

    Just to be clear, you can ENGINEER a coil speed up under load, and when Matt and I began work on the big generator, we worked with several different coil sizes, wire sizes, number of strands and lengths of wire. That original coil was ENGINEERED to BARELY speed up under load. We had coils that would cause the motor to speed up MORE, but what we wanted was the MOST OUTPUT under load without causing the drive motor to SLOW. So NONE of these coils cause the motor to speed up more than 10-12 RPM, but they also do NOT slow it down when loaded.

    Anyway, that is where I am now. Will the iron on the rotors make enough difference in magnetic flux to compensate for the cost in amp draw on the motor turning them, or would it be more beneficial to add one or two more plastic rotors that the motor can spin at high speed with no problem and 12 more air core coils that cause it to speed up under load. Those are the kind of things I want to know and intend to find out.

    We have a couple of VERY interesting roads of research to go down with this that are giving us interesting results.

    Anyway, that's the update. Probably nothing more from me until I get my coil tester back from the machinist next week.

    I appreciate all the GOOD information guys, and the ideas to try. I will post some videos when I start testing coils.

    Dave

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  • wayne.ct
    replied
    Thanks

    Yeah, thanks for the additional description, comments and the video. I was trying to visualize it and now I get it.

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  • Turion
    replied
    The disks in the video are 1/4 inch thick derlin (sp) plastic. The magnets are also 1/4 inch thick, so not recessed.

    I also have steel and aluminum rotors all that same size. Gonna get some steel rotors to back those plastic ones so I can see the effect on the flux in the coils. These are the same rotors I have on my big generator, which is why I am using them for this testing.
    Originally posted by dragon View Post
    It's actually N*A*R*B*P*2 = voltage. Yes doubling turns doubles voltage. This is for finding open circuit voltage only - no loads.

    Your quite right it doesn't include any dimensional variables but as long as all the variables are correct then it will determine voltage output reasonably well. What I mean by correct variables is that once dimensioned, the numbers used in the formula conform to the actual build. I've used it to design alternators for many years and for the most part it is quite accurate within a couple volts +or-.

    Very nice test rig Turion ! Are those steel discs? It looks like the magnets are recessed in the disc, am I seeing that right?

    Leave a comment:


  • dragon
    replied
    Originally posted by wayne.ct View Post
    Hi Dave, I'd like to see a picture of your coil testing stand, if you would be willing to share it. The NARBP*2 formula looks appropriate, but what does the factor of 2 represent? Should it be NARB times P squared? Does doubling the number of turns really double the voltage? I don't think so because you are not considering the size of the load, the resistance of the wire in the coil and the orientation of the coil. NARBP represents five factors, N, A, R, B and P. Where are the factors that represent the physical arrangement of the components? I would think the list of questions could be expanded.

    With so many factors to consider, why don't knowledgeable people share more details of what works and what doesn't? (It's probably fear of MIB, but I digress.) I hope some good ideas and concepts find there way into this thread.
    It's actually N*A*R*B*P*2 = voltage. Yes doubling turns doubles voltage. This is for finding open circuit voltage only - no loads.

    Your quite right it doesn't include any dimensional variables but as long as all the variables are correct then it will determine voltage output reasonably well. What I mean by correct variables is that once dimensioned, the numbers used in the formula conform to the actual build. I've used it to design alternators for many years and for the most part it is quite accurate within a couple volts +or-.

    Very nice test rig Turion ! Are those steel discs? It looks like the magnets are recessed in the disc, am I seeing that right?

    Leave a comment:


  • Turion
    replied
    Coil test stand

    Coil stand - YouTube

    This is a little video of the stand. I have it in the back of my car to take it to the machine shop to have spacers cut that are slightly bigger than the bobbin.

    Leave a comment:


  • wayne.ct
    replied
    Coil testing stand

    Hi Dave, I'd like to see a picture of your coil testing stand, if you would be willing to share it. The NARBP*2 formula looks appropriate, but what does the factor of 2 represent? Should it be NARB times P squared? Does doubling the number of turns really double the voltage? I don't think so because you are not considering the size of the load, the resistance of the wire in the coil and the orientation of the coil. NARBP represents five factors, N, A, R, B and P. Where are the factors that represent the physical arrangement of the components? I would think the list of questions could be expanded.

    With so many factors to consider, why don't knowledgeable people share more details of what works and what doesn't? (It's probably fear of MIB, but I digress.) I hope some good ideas and concepts find there way into this thread.

    Leave a comment:


  • DavidE
    replied
    Turion

    Love your post - questions, questions so many questions. But I think your answer is contained more by the kind of energy that you wish to manifest... and why.

    The kind of energy that you want to manifest first will build the energetic foundation before you get to transforming this energy into another more usable form (depending on devices to power).

    Honestly this is one of my favorite topics of late... and I think that there are many hints located in the current grid system about how this works. Certain forms of energy are created for distribution, others components are employed to transform frequency of this signal and condition this same power to a lower frequency power for use at the plug. And also a footnote to consider, where in the system are earth grounds utilized? At the point where the opposing distance between potentials needs to be the widest (to deliver the appropriate output).

    Technically I speculate that higher frequency power signals have an offsetting linked component that consist almost entirely of an ambient energetic... a connection with a form of primordial energy. As soon as you on purpose or by mistake lower the frequency accordingly, the ambient component is then replaced with amperage. Voltage in a line simply provides the pushing force which to deliver to X location.

    If you take a look at what some successful inventors have done to get X results, they focus on range of opposing potentials, and resonance... then condition power for use.

    Even more controversial, I further speculate that resonance opens the energetic door to potential beyond local, to that of non-local space. Different gradients of resonance may open even denser forms of energetic potential.

    There used to be a YouTube up that was demonstrating a commercial class Russian device that at the collection point utilized 30 gauge wire. Now how much typical conditioned house power can you put through this hair fine wire? You know the answer to this, not very much. So what WAS IT collecting?

    This for me suggested that collection or formation of source energy might require us to better understand the most elemental forms of power first.

    Then the rest of the circuit ends up being a series of math problems (voltage/frequency reduction) which is far easier to grasp with current technology/tools.

    Leave a comment:


  • bistander
    replied
    Originally posted by dragon View Post
    Magnets have a flux rating regardless of their thickness, .......
    Hi dragon,

    Actually magnet would have a flux density rating (B), which is the material residual induction, Br. Also the rating would include the material's intrinsic coercive force, Hci. And the flux will depend on the thickness (typically called the length along the axis of magnetization) as well as other parameters of the space surrounding the magnet.

    Here is a link to a pdf tech-notes which explains quite a lot about magnets.



    Regards,

    bi

    Leave a comment:


  • dragon
    replied
    Magnets have a flux rating regardless of their thickness, getting the coil to move through the maximum flux is the main objective. The magnets rating includes both sides, for instance if it has a rating of 10000 gauss then the surface reading of one side will be 5000 gauss.

    You can increase the gauss of one side by placing it on an iron or steel backing. This will shift a considerable amount of flux to one side. So instead of only 5000 gauss you may get surface readings of up to 7500 gauss.

    Using a dual rotor system where the magnets are placed on steel discs and placed face to face with the only gap being the stator you create a near perfect flux path where the coil sees nearly the entire flux rating of the magnet.

    The general rules of thumb: The thickness of the steel mounting disc should be equal to the thickness of the magnets. The spacing of the magnets should be no less than their thickness other wise they will start fringing therefore closing the path between them drawing flux away from the coils.

    The overall efficiency of the alternator is related to how well you direct the flux through the coils, amperage has a direct relation to resistance.

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  • Turion
    replied
    dragon,
    You make it all sound so cut and dried, but I am not convinced that it is. Take your statement that amperage is controlled by wire size. Are we sure that the THICKNESS of the magnet has no effect on amperage, and if so, what effect. Plus there is the matter of the air gap between coil and core as well as whether you have rotors at both ends of the coil or not. That does not even take into account what might be the minimum core size for producing maximum magnetic flux in a coil of this specific size so as NOT to offer any more attraction to the magnets on the rotor than necessary. And then there is STILL the matter of what is the optimum core material to produce amperage as well as voltage. Variables upon variables is what we are dealing with here. At least those are the things I am taking into consideration in my testing of coils. Perhaps needlessly, but I continue to see changes in results with adjustments in specific variables.

    Dave

    I'll leave what I wrote, but add this edit because sometimes I speak without really thinking it through. When I was talking about thickness of the magnet, what I really meant was weight, which is essential when producing the most output. An N42 neo will not produce as much flux as an N52 of the same size. (both may be overkill) So you might have to have a "thicker" N42 or one with more surface area to produce the same effect as an N52, if that makes sense. And that would add weight to the rotor which could cause more amp draw. I know you mentioned strength of the magnet in your variable, but it is strength in relation to size that I am thinking of here. Sometimes, depending on design, having large magnets out at the rim of a big rotor adds to the flywheel effect and can be a positive thing.
    Last edited by Turion; 08-12-2015, 07:28 PM.

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  • dragon
    replied
    NARBP*2 is the equation for finding voltage of a given coil

    N= number of turns
    A= area of magnet (sq inches * .000645 - 1 magnet)
    R= revolutions per second
    B= strength of magnet in tesla's
    P= total number of poles

    This is a basic formula for an air core alternator - iron core's present another group of variables.

    For the basic experimenter and/or where some variables are unknown you can wind a test coil and measure voltage at a known rpm, for example....

    Wind a test coil with, say 10 turns, spin it up to the rpm you want your design to produce peak output, measure the voltage. For this example we'll say at 1000 rpm the coil produced 2 volts. We need to know the volts per turn so 2 volts / 10 turns = 0.2 volts per turn. Let's say I want 24 volts output and there is only one coil needed, 24 volts / 0.2 volts per turn = 120 turns needed.

    If you have a 12 pole single phase with 12 coils with the coils wired in series then the 120 turns can be shared between them or 10 turns per coil

    If you want a 3 phase unit using 12 poles and 9 coils (3 coils per phase) wired in star you can reverse engineer the outcome by taking the 24 volt goal / 1.73 = 13.87 volts per phase, then divide this by the number of coils in series.... 13.87 / 3 = 4.62 volts per coil. 4.62 volts per coil / 0.2 volts per turn = 23.1 turns per coil to achieve the 24 volt goal.

    Amperage is controlled by wire size, the size of wire is determined by the area you have to work with in a given design.
    Last edited by dragon; 08-12-2015, 06:21 PM.

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