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  • Hi Uusedman,

    When you say "collecting the back EMF" how are you doing the load part exactly? Are you just connecting a light bulb after the diode?

    It has many advantages to collect that Back emf (fly back or inductive collapse really) into a low impedance source like a cap or battery and connect your load on that. Not straight to the back emf recovery diode. It tends to often be a too high resistance for the fast spike to dump into. And can cause because of that rpm drops. (And amp draw increases)

    In my view one wants to collect that flyback as quick as possible, meaning it must be able to dissipate itself fast into a load/cap/battery. You want the core in each cycle to also have time to 'relax' and reset itself to a more neutral polarity condition before the next pulse happens. You want to do it all in one cycle: Pulse the core with for example 33%duty, then somehow collect all the flyback in 33% duty and in the final 33% duty time you want the core to do nothing and relax back to a zero magnetic state as much as possible. If the core is not relaxed/reseted and still has like a 75% remanent magnetic field from the last attraction cycle you will have very little real field change and because of that bad performance. So it is important that you dump the flyback in a low resistance load, so a cap would be best. Your bulb can be connected to the cap. Hell even better would be having a circuit that dumps the cap to the load in between each dc pulse.



    Regards,
    Steven
    Last edited by nali2001; 04-23-2009, 04:52 PM.

    Comment


    • I am dumping the inductive collapse into a 12V car battery. The source is a normal power source with a 50V 6Am max.



      Originally posted by nali2001 View Post
      Hi Uusedman,

      When you say "collecting the back EMF" how are you doing the load part exactly? Are you just connecting a light bulb after the diode?

      It has many advantages to collect that Back emf (fly back or inductive collapse really) into a low impedance source like a cap or battery and connect your load on that. Not straight to the back emf recovery diode. It tends to often be a too high resistance for the fast spike to dump into. And can cause because of that rpm drops. (And amp draw increases)

      In my view one wants to collect that flyback as quick as possible, meaning it must be able to dissipate itself fast into a load/cap/battery. You want the core in each cycle to also have time to 'relax' and reset itself to a more neutral polarity condition before the next pulse happens. You want to do it all in one cycle: Pulse the core with for example 33%duty, then somehow collect all the flyback in 33% duty and in the final 33% duty time you want the core to do nothing and relax back to a zero magnetic state as much as possible. If the core is not relaxed/reseted and still has like a 75% remanent magnetic field from the last attraction cycle you will have very little real field change and because of that bad performance. So it is important that you dump the flyback in a low resistance load, so a cap would be best. Your bulb can be connected to the cap. Hell even better would be having a circuit that dumps the cap to the laod inbetween each dc pulse.



      Regards,
      Steven

      Comment


      • prewound coils

        Hi

        I was hoping someone could give me advice on prewound coils. I made a polycarbonate jig, similar to Jetijs's. I am having trouble getting the coils off. On my first setup I used Teflon tape between the coil and the jig. The epoxy managed to get through some cracks and made it difficult to get off. Second I used a silicon spray, but i didnt use the teflon tape. I still got some of the epoxy bonding with the jig.

        Would rounded corners on the jig help? I was thinking of using some kind of thin cardboard that I can use silicon spray on and put that in between the coil and the jig.

        With Gratitude,
        Chris Corkum
        Progress comes to those who train and train. Reliance on secret techniques will get you nowhere.
        -Morihei Ueshiba

        Comment


        • Chris,
          round corners help a lot. First I wrapped the acrylic core with several layers of non stick baking paper, the one that is used for baking cookies. Then two layers of electric tape. I put some plastic tape also to the walls of the support end plates. This works well. After the epoxy is cured, the coil pulls of with a light push and the electric tape that sticks to the coil comes off easily.
          Hope this helps.
          It's better to wear off by working than to rust by doing nothing.

          Comment


          • @Jetis

            My reed switch keep on blowing, I am going to try to trigger the attraction through a bedini style circuit. You think it is a good idea to excite the base of the transistor through inductor magnet spining?

            Comment


            • uusedman, I don't know why your reed switch keeps blowing, I had no problems with that circuit when I worked on my first attraction motor, I even used much smaller and weaker reed switches and they worked just fine, the onlu problem was that the contacts were getting magnetized because of the use of strong neo magnets. That is why I switched to optical switching.
              I don't know about the inductor switching, but you can try this out and see how it works. Good luck!
              It's better to wear off by working than to rust by doing nothing.

              Comment


              • I am going to buy some more reed switches and transistors, they keep blowing .

                The following is a circuit I tried to make for the switching, it was not working. give me your thoughts on it.



                Originally posted by Jetijs View Post
                uusedman, I don't know why your reed switch keeps blowing, I had no problems with that circuit when I worked on my first attraction motor, I even used much smaller and weaker reed switches and they worked just fine, the onlu problem was that the contacts were getting magnetized because of the use of strong neo magnets. That is why I switched to optical switching.
                I don't know about the inductor switching, but you can try this out and see how it works. Good luck!
                Last edited by uusedman; 11-25-2010, 06:00 AM.

                Comment


                • don't know. maybe the induced current in the trigger inductor was too low. I think lighty or Eric could answer this better
                  It's better to wear off by working than to rust by doing nothing.

                  Comment


                  • Bedini G-Field Generator?

                    Is there a thread or a link to a document that describes the Bedini G-Field Generator?

                    I read something about this device that it actually speeds up when under load..... Excellent....

                    Thank you and have a most excellent weekend!

                    Tj

                    Comment


                    • This is my latest update with the transistor firing position. It shows some progress toward getting the results we are yearning.

                      Next step is to put 16 gauge inductor, 50 - 75 turns.

                      P.S. I canceled the idea of triggering a inductor to pulse the motor, it was easier to do with a reed switch. Last night, All components stay intact and functioned properly

                      YouTube - Rotary Attraction 2-1

                      Comment


                      • nice!

                        Originally posted by uusedman View Post
                        This is my latest update with the transistor firing position. It shows some progress toward getting the results we are yearning.

                        Next step is to put 16 gauge inductor, 50 - 75 turns.

                        P.S. I canceled the idea of triggering a inductor to pulse the motor, it was easier to do with a reed switch. Last night, All components stay intact and functioned properly

                        YouTube - Rotary Attraction 2-1
                        congratulations!!
                        a couple of suggestions
                        1. if you are going to disconnect the kick back while running the motor put an NE2 600v neon light bulb (like the ones recomended in bedini circuits) accross the emitter to collector. this bulb will only light up if you have no load connected with which to dump the spike. that large ticking sound is the kickback trying to discharge accross the next easiest pathway, most likely your tranny, so if you proceed with out it and say, up the voltage, you can ruin the tranny. i know, i have!!

                        2. keep in mind that as you improve the motor and up the rpms, your magnets are not glued down or otherwise very secure. this could be hazardous to you or your magnets if one should fly off!!

                        3. an annalog meter is a much better way to view the amperage ebay has some very nice cheap 2, 5, or 10 amp meters with shunts if you want them. i recomend all 3 so you can choose the best range for your tests. a digital meter has a sampling rate at a fixed frequency so it will give you irratic readings.

                        4. while an analog meter will give you a better reading, keep in mind that that it is an "average" reading, the goal with this motor is a large amp spike with a short duty cycle. and while the amp meter on the power supply is giving you an average consumption keep in mind the initial spike might require well over 5 amps in a short period of time. your supply might be current limmiting it. i know, because my first motor was a small fan motor about the size of my hand and while on average it ran at 150 to 300 milliamps it require more than the 3amps my supply could provide at the initiation of the "ontime". to fix this you can eather use "good wet cell auto, motorcycle, or ups batteries" these will not limit the current. or what i did for my power supply add some 1.2 farad audio caps in paralell with the power supply. the caps can handle the spike and the supply can more continually charge the the caps. just keep in mind that caps are leaky and you have to account for that when determining overall efficiency.

                        5. try moveing the reed slightly back and forth while the motor is running you will be suprised that this changes the timeing and the rpms will increase or decrease.

                        hope that helps!!
                        Eric

                        Comment


                        • @Eric

                          I installed a neon bulb from the emitter to the collector to protect my transistor (Thanks ! ). My transistor runs well and does not go out easy anymore.

                          Once I get the 16 gauge copper wire, i will have to glue my magnets, since that will increase my RPM. Plus, I want to play it safe so I have to do it any way. I did buy a photo trigger component, maybe, that will be better once i get the hang on this motor.

                          I put 2 analog DC Ampere, the first 3 AMP and the second 1 AMP.

                          The spike problem will have to be solved once I have the basics done

                          Now get this, When Dr. Lindemann placed his hand on the rotor that did not increase the AMP, however, my motor increase the AMP according to the pressure i apply. What should I do?

                          I did upload a video of the improvements, once it is done, I will post the link.
                          Thanks for your help.

                          Comment


                          • uusedman, mu motor and also Stevens motor also increases the currentdraw under load. But with the increased current, the recovery also increases. So I guess that is ok.
                            It's better to wear off by working than to rust by doing nothing.

                            Comment


                            • This is the video with the improvements

                              YouTube - Rotary Attraction 2-2

                              @ Jetis, I thought when Dr. Lindemann did his video the AMP did not increase. We got to ask him.

                              Comment


                              • When you check your RPM's they are only be 1/4 your actual reading because your getting a reflection off all 4 magnets. You can either divide the total by 4 to get the actual RPM or put some non reflective coating on 3 of the magnets.

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