Working Magnetic Motor on you tube??

[Omnibus]

@blue_energy,

Sorry to bother you with this boring stuff after such an inspiring evening you had. Yes, I understand that but my only goal was to see if we can connect somehow the rpm with the spectral pattern. We can't, it turned out. As for the 174Hz you're right, the conditions have to be kept the same to "hear" that tone. Unfortunately, I don't have anything here to accomplish that save the fact that things such as a Dremel will introduce additional noise which will interfere (not sure it can be filtered good). Anyway, I don't see comparing the acoustic characteristics of the device being of much use for its successful replication but I may be wrong. Do you think any successful machines would sound the same? Do, say, working internal combustion engines have common major acoustic patterns?

[Yadaraf]

RE Harmonics

I performed an FFT on the 4700 RPM audio (4733?) and then applied a harmonic ruler to the far left peak (176.6 Hz). 

The peak at 871.7 Hz looks 5th to me.   


Cheers,   

Yada..
.

EDIT:   Hmmm.  I didn't do anything and now I notice the figure is missing.  Mods?  What happened?  Dunno, so reposted, but had to create a new image name.  FYI previous image(s) had been viewed 136 times.

EDIT:  If there is a 5th, where are the 2nd, 3rd, and 4th?  In any event, during acceleration a frequency shift is observed in both the low tone and the high tone, so they are coupled.

EDIT:  Note the vertical black lines are superimposed harmonic ruler lines.

[Yadaraf]

RE:  CSI Yadaraf and the Fifth Harmonic

While investigating the Fifth Harmonic in rotating devices, I found an article in Mechanical Engineering Magazine that discusses "unusual speeds" in motors .  There might be some relevance.

=====
"For the fifth harmonic of the incoming current, 300 electrical degrees separate the pole/phase groups, Bourne said. That's five times the separation of the fundamental phases. But 300 degrees is really minus 60 degrees for a periodic function, Bourne explained.

So adjacent phases of the fundamental and the harmonic frequencies are exactly opposite. For a three-phase machine, that means that the fifth harmonic creates a field of the same number of poles as the fundamental, but with a negative phase sequence, Bourne said. And that field rotates counter to the fundamental, at five times the speed.

Similar arguments apply to other harmonics, Bourne said. In a three-phase machine, multiples of the third harmonic are neutral, producing no negative effect, but making no contribution either. Harmonics 5, 11, 17, and so on produce reverse sequence currents. Harmonics 7, 13, 19, etc., produce nonsynchronous forward sequence currents, he said.

"Ask any motor person in the world what happens when you run a motor on the fifth harmonic," said Isaiah Cox, CEO of Chorus. "They will tell you it runs in reverse at five times the speed. It is gospel."

====

... http://www.memagazine.org/mepower01/5thharm/5thharm.html

CSI Yadaraf on the scene.   

Cheers,   

Yada..
.

[Yadaraf]

RE: CSI Yadaraf and the Fifth Harmonic (redux)

I took 25 samples of the HI and LO tones during acceleration in the WMV file.  Here's the data.

S      LO          HI       Ratio
=====================
01   164.19   826.34   5.03
02   166.88   826.34   4.95
03   166.88   820.95   4.92
04   166.88   831.72   4.98
05   166.88   839.79   5.03
06   166.88   839.79   5.03
07   169.57   831.72   4.90
08   169.57   837.10   4.94
09   169.57   845.18   4.98
10   169.57   847.87   5.00
11   170.92   841.14   4.92
12   170.92   843.83   4.94
13   170.92   857.29   5.02
14   170.92   846.52   4.95
15   172.27   847.87   4.92
16   172.27   850.56   4.94
17   172.27   850.56   4.94
18   172.27   864.02   5.02
19   174.96   866.71   4.95
20   174.96   864.02   4.94
21   174.96   869.40   4.97
22   174.96   866.71   4.95
23   174.96   866.71   4.95
24   177.65   866.71   4.88
25   177.65   872.09   4.91

Note the ratio at each sample is very similar.   The average ratio is 4.96 (i.e. 5:1).  To me this suggests a fifth harmonic. 

If the HI and LO tones were related to the speeds of the rotor and stator, then I think we should expect a ratio closer to 4:1, not 5:1.



Cheers,   

Yada..
.

[CLaNZeR]

Some new Videos, these new Stator bearings are great!

First big one for Yada, some sound samples.
http://www.overunity.org.uk/ocpm/CLaNZeR-OCPM-YADA.wmv

Or Youtube: http://uk.youtube.com/watch?v=D9v9ISMlj1g


Next one shows how easy it is to latch into AGW, including all 3 stators going AGW at over 1500RPM.
http://www.overunity.org.uk/ocpm/CLaNZeRSNewBearingsLatch.wmv

Or Youtube: http://uk.youtube.com/watch?v=VE3aboJWhY0

New Rotor Dimensions, ummm why did I bother LOL.
http://www.overunity.org.uk/ocpm/CLaNZeRSNew18mmRotor.wmv

Or Youtube: http://uk.youtube.com/watch?v=9XG9MaLXVVg

Cheers

Sean.