Thane Heins Perepiteia Replications

[i_ron]

@i_ron

Regarding your scope shots, can you explain like in slow motion, what is happening to make the curve go up then down. Seems to me that since the magnets are separated having either north then south facing the core all moving in the same direction, would it be correct to say the north magnet makes the top half curve and the south magnet then makes the bottom half curve and so on (or vise-versa depending on the core winding direction). Does this mean each two magnets makes one full wave and therefore the overall frequency should be (total magnets divided by two, times the rpm).

But then as the second half of the north leaves the core, the first half of the south is already on the core so there has to be a doubling curve somewhere to show the south starting before the north leaves the core. So it is rather weird to see such a smooth curve as you are showing. Or am I confusing the issue.

Last question. I saw there are some neo magnets that have a nice conical center hole for easy mounting. Could these be used with conical headed aluminum screws to simplify the magnet mounting on a rotor. I am considering this for a trial build but am wondering if such a mounting would be secure enough when exposed to such rotations. I am thinking of using a 1/2" or 3/4" thick aluminum rotor (to have some good mass in the wheel) so there is no drag potential between an energized coil core and the metal of the wheel.

Hi wattsup,

Yes, you have it nearly cased... the gauss meter outputs a positive voltage for a north pole and a negative voltage for a south pole.

So looking at the bottom trace you see the voltage generated by a single magnet and the zero crossing in the middle is TDC of the pickup coil's core with the first positive going peak triggering the display.

The top trace is exactly as you think, the top part of the sine wave being the rising level of flux in the core from the north pole magnet and the same then with the bottom half from the south pole.

So to see it more clearly have another look at the link posted previously...

http://www.koehler.me.uk/animation/e_and_m_magnets.htm

here you can see how the flux and the voltage relate.  In the animation you see the one north pole causing the one flux hump but both sine's
But the next south magnet in my case should be right on top of the south sine and extend and/or double it. Therefore, if it is not an "M" wave you can say that the receding N and the approaching south cause the negative half of the sine wave and the receding south and the approaching north cause the positive half of the sine wave.

Clear as mud?

But it is interesting also to view my previous posts on voltage generation, 'cause all sorts of weird things take place under load... and shorting.

Ron

oh, nearly forgot... take a magnet with you and look for SS screws/bolts, they are much stronger that aluminum and some are quite non magnetic, hence the magnet to check...

Of course a better way would be to pocket into the aluminum disc for the magnet... a one inch magnet will sit nicely in a 1/8th pocket made with a  1 inch wood working spade bit... if you have a nice slow turning drill press.

[CRANKYpants]

http://jnaudin.free.fr/images/magconfig.gif

Something like the scope shot on the right?

I know this has been discussed quite a few pages ago but I felt like pointing this out.

IT WAS DISCUSSED INCORRECTLY THEN AS IT IS NOW.

YOU SHOULD NOT BE LOOKING AT THE VOLTAGE - YOU SHOULD BE LOOKING AT THE CURRENT SINE WAVE!

AND THE CURRENT AND VOLTAGE ARE IN PHASE ACROSS A PURELY RESISTIVE LOAD...
AND THE LOAD POWER FACTOR IS TRANSFERRED BACK TO THE COIL AND IT = 1.

THE CURRENT (AND VOLTAGE) ARE MAXIMUM AT TDC AND START TO CHANGE DIRECTION ONLY WHEN THE MAGNET STARTS TO MOVE AWAY FROM TDC BECAUSE THE CURRENT AND VOLTAGE ARE IN PHASE.

AND AS I SAID BEFORE - IT IS A MISTAKE TO LISTEN TO I_JUDAS AT THIS POINT BECAUSE EMOTION AND EGO HAVE REPLACED SCIENCE AND REASON.

THE BLIND SHOULD NOT LEAD THE BLIND
TO THE ABATTOIR.

T

[minde4000]

Here is my double sided rotor - half setup. Still looking for laminates.

[aladinlamp]

Here is my double sided rotor - half setup. Still looking for laminates.

Hi
whats the diameter of the rotor

thanx

[derricka]

...IT IS A MISTAKE TO LISTEN TO I_JUDAS AT THIS POINT BECAUSE EMOTION AND EGO HAVE REPLACED SCIENCE AND REASON.

THE BLIND SHOULD NOT LEAD THE BLIND
TO THE ABATTOIR.

T

So which blind mouse do I follow:  "I_JUDAS"  or "CrankyLUKE6:42" ?


Trailblazers creating new trails need to put up more markers and create better maps
than they think is probably needed for the job. Likewise, hikers on new trails, without a well worn path to follow, need to be able to read maps and follow markers, all while resisting the well intentioned urge to fill in perceived missing markers. Any failure in this system, and the hiker will never agree that they reached the same destination as the trailblazer. Ideally, the first hikers should compare notes with the trailblazer, and be able to mutually accept ideas for improvement.

"BlindMouse3"