Confirming the Delayed Lenz Effect

[gotoluc]

It must be in the several Henry range.  A google search brought this:
primary L=68.2mH 
HV secondary L=15.5H
(from this link: http://sci.tech-archive.net/Archive/sci.electronics.cad/2008-02/msg00082.html )

Maybe the laminations could work up to some hundred Hz for the older type transformers (nowadays there are ovens with switch-mode power supply to get the HV too).

Cheers,  Gyula

PS: just recall this pdf file member poynt99 uploaded that includes info on oven transformer, page 17:
Primary: R= 0.35 Ohms; L= 44.4mH
Secondary: R= 88 Ohms; L= 19.3H
(from this: http://www.overunity.com/index.php?action=downloads;sa=view;down=209 )

Hi Gyula,

I have a Microwave oven transformer and the Primary is 69mH and Secondary is not measurable since my Inductance meter can measure 20H max, so it must be just a little over 20H.

I'll give it a try with my Signal Generator to see if I can find a frequency that the load is not reflected to the Primary.

Luc

[gotoluc]

Hi everyone,

here is a video demo of a possible Delayed Lenz Effect with attached scope shots below.

A Microwave Oven Transformer Primary is connected to the output of my Signal Generator. The Primary of this Transformer is 69mH and the Secondary is around 21H. I tested the Secondary in three different conditions, not connected (open circuit), connected to a Neon bulb and Short circuited.

First scope shot is MOT with no Load on Secondary
Second scope shot is MOT with Neon Bulb Load on Secondary
Third scope shot is MOT with Secondary Shorted

Link to video: http://www.youtube.com/watch?v=ne-wJqZVDvs

Please post your comments please

Luc

[Magluvin]

Hey Luc

Good show.  ;]   Seems like the freq is high for 20h.  Maybe try a 1uf or .5uf cap across the sec to lower the freq.  Marius and I have seen more power out when using a cap in series with a load. Larger cap, lower freq.

Its very cool that the mot works here as many seem to have them, or can be had easily, and can get to work on these ideas. ;]

Mags

[gyulasun]

Hi Gyula,

I had to pickup my Digital Caliper from storage to re-check the diameter of the wire. It is actually 0.50 mm with enamel coating. The DC resistance is correct @ 4.4 Ohms so you should be able to figure out the wire length and approximate amount of turns.

Let me know if something does not look right.

Thanks for your time

Luc

Well, the 4.4 Ohm coil made from 0.5mm OD copper wire has a wire length of about 49 meter.  This has a better chance to fill onto that core. Using the Mini Ring core calculator, for such sized toroid core 142 turns gives a full single layer coil directly on the surface from the 0.5mm OD wire and alltogether roughly 5 to 5.7 times more layers above the first one could give the 811 turns needed for the 7.5 Henry inductance.
( http://www.dl5swb.de/html/mini_ring_core_calculator.htm )

Gyula

[gotoluc]

Hey Luc

Good show.  ;]   Seems like the freq is high for 20h.  Maybe try a 1uf or .5uf cap across the sec to lower the freq.  Marius and I have seen more power out when using a cap in series with a load. Larger cap, lower freq.

Its very cool that the mot works here as many seem to have them, or can be had easily, and can get to work on these ideas. ;]

Mags

Hi Mags,

I actually can get the delayed Lenz effect at 900Hz or even lower using a MOT but when I would change the load on the Secondary like I did in the video demo (no load, Neon bulb then shorted) Lenz would appear in one of the condition if I didn't re-adjust the Frequency. Maybe that's why Overunityguide did not demonstrate a short in his Transformer video. However, I found that at 4.9kHz it had no effect what so ever on the primary with what ever I did to the Secondary, so I decide to used that Frequency to make the video demo simple.

I will be experimenting with capacitors but that will be to get the Primary into Resonance and hopefully at a Frequency the Secondary will have Lenz delay. Should be cool when that happens

Luc