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  • #31
    I think Fairdeal's last sentence says something: What is a "real" load for the setup?

    There seems to be some pondering about what happens to the power; there is simply not much created when the wires are shorted. Boscoe says 34 amps and later advises at less than one amp. That equates to to less than 34 watts. One can say that that generator is not working effectively, "cavitating" if you like with a hopelessly mismatched "propellor". Or look at it as if the engine is revving at full power revs but in neutral, say 6000rpm but putting out very little power,

    What happens to the excess power? It is dissipated or shared between the regulator and the windings, as I mentioned previously, in (inverse) ratio to their respective resistance.

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    • #32
      Originally posted by zenoahphobic View Post
      I think Fairdeal's last sentence says something: What is a "real" load for the setup?

      There seems to be some pondering about what happens to the power; there is simply not much created when the wires are shorted. Boscoe says 34 amps and later advises at less than one amp. That equates to to less than 34 watts. One can say that that generator is not working effectively, "cavitating" if you like with a hopelessly mismatched "propellor". Or look at it as if the engine is revving at full power revs but in neutral, say 6000rpm but putting out very little power,

      What happens to the excess power? It is dissipated or shared between the regulator and the windings, as I mentioned previously, in (inverse) ratio to their respective resistance.
      One (1) volt.

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      • #33
        Originally posted by fairdeal View Post

        So the full available amount of amps DOES "go into" the R/R - even though nothing "comes out".

        This is fascinating; so many mysteries.

        If all of the current, is already being "dissipated", why does any of it flow out when a "real" load is connected" ?
        A zener diode is opening and closing to shunt current to ground. To control the voltage.

        Voltage below say 14.6 volts and the zener is open. Voltage rises to above 14.6 volts and the zener is closed.

        When the diode is open current will flow to the battery. When the diode is closed current is shunted to ground. It is all happening so quickly that it appears to be a constant voltage to the battery.

        Two paths for current to flow. Out the R/R to a battery or internally to ground. Or a bit of both at the same time. Or so it seems.

        At my age in life, I am no longer absolutely positively certain of anything anymore. What once appeared to be is, is not. What once appeared to be not, is. And me can't even agree upon what the meaning of is, is.

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        • #34
          what is is?
          Dennis
          Keep life simple, eat, sleep, fish, repeat!

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          • #35
            Originally posted by boscoe99 View Post
            One (1) volt.
            Yeah one volt times 34amp equals 34 watts. I always mistype something.

            I might also take the opportunity, as an analogy to the overloading to the point that the load actually drastically reduces, and that is by jamming an electric motor down until it stops.

            Some torque may may remain but the power consumption goes down. Applicable to most AC or DC or permanent magnet electric motors.

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            • #36
              Originally posted by zenoahphobic View Post

              Yeah one volt times 34amp equals 34 watts. I always mistype something.

              I might also take the opportunity, as an analogy to the overloading to the point that the load actually drastically reduces, and that is by jamming an electric motor down until it stops.

              Some torque may may remain but the power consumption goes down. Applicable to most AC or DC or permanent magnet electric motors.
              I believe he said less than 1 volt, so it depends on how much less than 1 volt as to how many watts

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              • #37
                most the larger Yamaha RR's shunt excess current to ground. that is why most are water cooled.
                at school playing with a 300 HPDI we got almost 1000 volts AC from the stator with no load.
                don't know how much current you could actually make until the windings melted.
                the heat is also why I suspect the F350 rotors fail. man that rotor gets smoking hot in use.

                Comment


                • #38
                  Originally posted by rodbolt17 View Post
                  most the larger Yamaha RR's shunt excess current to ground. that is why most are water cooled.
                  at school playing with a 300 HPDI we got almost 1000 volts AC from the stator with no load.
                  don't know how much current you could actually make until the windings melted.
                  the heat is also why I suspect the F350 rotors fail. man that rotor gets smoking hot in use.
                  I can see ~ 1000 no load volts. 12 magnets smoking (moving quickly) by the lighting coils at 6000 RPM could very well do it.

                  The type of magnets used in the Offshore model are so strong they have to be handled carefully. Let two of them clamp together and it is a bitch to get them back apart.

                  Now if the design was done correctly I can't see the coils melting from excessive temperatures at maximum current flow. Only so much current can be made and the coils should be designed/sized for the electrical load, plus a margin of safety. But coils can and do fail for a number of reasons. Vibration being just one of many.

                  Excessive temperatures are suspected in causing the rubber dampener in the F350 flywheel to fail and in so doing resulting in damage to the crank shaft.

                  Designing a long running high output motor is not as easy as it may seem.

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                  • #39
                    Originally posted by boscoe99 View Post

                    I can see ~ 1000 no load volts. 12 magnets smoking (moving quickly) by the lighting coils at 6000 RPM could very well do it.

                    The type of magnets used in the Offshore model are so strong they have to be handled carefully. Let two of them clamp together and it is a bitch to get them back apart.

                    Now if the design was done correctly I can't see the coils melting from excessive temperatures at maximum current flow. Only so much current can be made and the coils should be designed/sized for the electrical load, plus a margin of safety. But coils can and do fail for a number of reasons. Vibration being just one of many.

                    Excessive temperatures are suspected in causing the rubber dampener in the F350 flywheel to fail and in so doing resulting in damage to the crank shaft.

                    Designing a long running high output motor is not as easy as it may seem.
                    Do you think it is possible that electrical inductive heating could be part of the overheating problem of the flywheel?

                    Comment


                    • #40
                      Originally posted by 99yam40 View Post

                      Do you think it is possible that electrical inductive heating could be part of the overheating problem of the flywheel?
                      I think so. Part of the modifications to the motor when the rotor was changed was also changing the shroud that covers the flywheel/rotor to add ventilation slots.

                      Playing with my generator, it does not get hot when turning if no electricity is being made. Add an electrical load and it will get hot. Real hot. Even with a fan to draw air through it. I suspect the same to be true for the F350 lighting coils.

                      Coils mounted underneath the rotor. In a closed space. Heat rises. To the rotor. Heat deteriorates rubber.

                      Seems a shame to generate heat underneath a flywheel. As opposed to in a separate belt driven automotive style alternator. A shame to use HP to create electrical power that is not needed and which then gets wasted.
                      Last edited by boscoe99; 12-25-2018, 12:20 PM.

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                      • #41
                        There is a good reason why most alternators (cars, trucks, airplanes, etc.) get mounted up front. For better cooling.

                        In some airplane alternators (creating many hundreds of continuous amps) blast tubes are employed to direct cooling air to them.

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                        • #42
                          Originally posted by boscoe99 View Post

                          I think so. Part of the modifications to the motor when the rotor was changed was also changing the shroud that covers the flywheel/rotor to add ventilation slots.

                          Playing with my generator, it does not get hot when turning if no electricity is being made. Add an electrical load and it will get hot. Real hot. Even with a fan to draw air through it. I suspect the same to be true for the F350 lighting coils.

                          Coils mounted underneath the rotor. In a closed space. Heat rises. To the rotor. Heat deteriorates rubber.

                          Seems a shame to generate heat underneath a flywheel. As opposed to in a separate belt driven automotive style alternator. A shame to use HP to create electrical power that is not needed and which then gets wasted.
                          I thought you said the unit has the same amount of AC current flowing thru the coils when loaded or unloaded on the DC side.
                          so why would it matter if the dc side was or was not loaded?

                          And the electrical inductive heating I was trying to refer to was the type that bearing heaters or stove top uses to heat up metal, Just in case you were thinking of something else.

                          and I agree wasting HP to create electricity that you just shunt off is dumb
                          Last edited by 99yam40; 12-25-2018, 01:03 PM.

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                          • #43
                            If the DC side (or the AC side) is not loaded then there is no current flow.



                            If and when loaded, the current will flow.



                            I might have been thinking of something else with respect to inductive heating. I was thinking of the coils heating up when current flows. As opposed to inductive heating of a metal part in proximity to a coil. Perhaps the rotor does experience inductive heating at the same time that it is absorbing heat from the hot coils.

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                            • #44
                              This from a website that offers PMA's.

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                              • #45
                                With Yamaha R/R connected while connected to a battery.

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