Has anyone seen Lasersabers new motor runs on 1000uf cap

[Pirate88179]

Mags:

Have you seen this stuff?

http://www.batterystation.com/curtisium.htm

Cutisium.  I bought some of these tiles a few years ago and, to me, it is the state of the art in glow technology.  Stick a few tiles in the sun for a minute, and they glow very brightly for 12-20 hours.  Incredible!  I can charge them with the light from a cfl, or LED light and they glow so brightly and for such a long time, it is amazing.  One day, I will build a house that has a wall of these that gets sun exposure during the day, and lights the room at night.

Bill

[conradelektro]

conradelektro,

I believe the reason why (your motor requires more power) is the amount of energy needed to overcome the inertia. Your rotor with the magnets is larger in diameter, weighs more, etc. It's a matter of greater mass and weight, I would think would be the reason why your motor requires greater energy to turn vs LaserSaber's motor.

What if you were to make your rotor out of Balsa Wood structure capturing the magnets, held in place with super glue? And the diameter was the same as LaserSaber's? (Note: Cut out as much material from the rotor as possible without weakening it to make the rotor as light as possible)

To run an equivalent energy efficient device you'll need to match or improve on it's ability, no?

@Billxx: I like if someone speaks up, only the exchange of opinions allows us to learn. I was thinking along this line as well (inertia, mechanical problems, wrong dimensions,..) but now I believe:

If a magnet of the rotor is near the Reed switch current flows. And this current is mainly determined by the DC resistance of the coils as long as we have very low frequency (like one rotor turn per second). So, measuring this current (when a magnet is in front the Reed switch) gives us an upper limit of the power draw of the motor.

For my motor this upper limit at 1 V supply Voltage is 1/540 = 1.8 mA (6 coils in series with 90 Ohm DC resistance each).

When the motor turns the Reed switch ON-time is about 20%, so, 1.8/5 = 360 µA. In fact I am measuring about 500 µA because the ON-time is may be a bit more than 20%, more towards 25% (results in 450 µA average power draw).

My motor turns with about 150 rpm with 1 V and 500µA, so all mechanical and wrong dimension problems are overcome with this power draw. By introducing a resistor into the circuit, e.g. a 5.6 K resistor I could bring the average power draw down to about 50 µA, but then the motor hardly turns (about 30 rpm and every disturbance stops it). So, the mechanical problems can be overcome with 1 V and 50 µA.

The reverse current of 10 1N60 germanium diodes (about 20 µA at 1 Volt) were not enough to make my motor turn. So, I would say that my motor needs at least 1 Volt and 50µA to turn, but I can not bring its power demand below 1 V 500µ A without introduction of further resistance into the circuit.

Sorry for the delay.  The coils seem to very between 1.6 to 1.7K.  The resistance on the six coiler is 9.9K.

No lets do the upper limit calculation for Lasersaber's motor with 6 coils in series 9.9 K DC resistance at 1 Volt supply Voltage:

1/9900 = about 100 µA

with about 20% Reed switch ON-time we get about 20 µA average current.

My motor runs nicely with 500 µA and very slowly with 40 µA, so, therefore it is plausible that Lasersaber's very well and precisely  built motor runs fast with 20µA and rather slowly with 1 µA average power draw.

I would say the explanation of the low power draw of Lasersaber's motor lies in the 9.9 K DC resistance of his coils, and then once we have this low power draw the mechanical advantages come into play as well.

What I want to say:

First one needs that very high DC resistance (impedance) of the coils and then a good mechanical build.

Let's say I get such 1. 6K to 1.7 K DC resistance coils and put them into my motor. It could happen that it will not turn (because of the bad build), but its power draw (after pushing it along by blowing a bit of air over it) will be as low as in Lasersaber's motor.

And I will build a motor with 1.6 K DC resistance coils from relays which I already found:

http://www.conrad.at/ce/de/product/503091/Serie-36-DC-Printrelais-Finder-361190244001-24-VDC-1-Wechsler-10-A-30-VDC250-VAC-AC1-2500-VA (R-Spule = 1600 Ohm, R-Spule = DC resistance)

http://www.conrad.at/ce/de/product/503614/Miniatur-Print-Relais-AZ943-15-A-Zettler-Electronics-AZ943-1CH-24DE-24-VDC-1-Wechsler-Max-15-A-Max-30-VDC300-VAC

It may be will not turn (because of mechanical problems) but it will have a similar low power draw.

But of course I hope it will turn at least slowly.

Greetings, Conrad

[gyulasun]

Hi Conrad,

Thanks again for doing the tests across the reed with the scope on it I still digesting your conclusions from it, pondering on how the diode reverse resistance plays its role.

On your latest post:  I assume those 1.6 kOhm relays from Conrad include a ferromagnetic core, can you remove them easily or no problem with them. 

Yes, the some uA current draw can only be explained by the huge impedance of Lasersaber coils (besides the big DC resistance the residual inductance must be in the some 10 times Henry range) and the small mass of the rotor.

Thanks, Gyula

[conradelektro]

I did some scope shots over the diode in order to show what happens while charging the cap. No battery in the system, the cap was first discharged and the charge up to the given Voltage by blowing an air jet over the rotor rim area.

One sees that the charging happens when the Reed switch is on (positive bump is cut of because the current runs into the cap) and the again with the BEMF spike. The positive bump of the AC current generated in the coils is cut off at the momentary cap Voltage.

Greetings, Conrad

[conradelektro]

Hi Conrad,

Thanks again for doing the tests across the reed with the scope on it I still digesting your conclusions from it, pondering on how the diode reverse resistance plays its role.

On your latest post:  I assume those 1.6 kOhm relays from Conrad include a ferromagnetic core, can you remove them easily or no problem with them. 

Yes, the some uA current draw can only be explained by the huge impedance of Lasersaber coils (besides the big DC resistance the residual inductance must be in the some 10 times Henry range) and the small mass of the rotor.

Thanks, Gyula

@Gyula: I hope that the scope shots over the diode will enlighten you. Feel free to indicate further scope measurements, I want to understand this motor fully. But I am not very skilled at electronics, so any help and any ideas are appreciated.

I have to first order the relays. Then I can dismantle them and look at their design. I hope that I can remove everything from the coils including the core. It was possible with the two types of relays I use so far (I called them "black coils" 280 Ohm and "white coils" 90 Ohm DC resistance). I still have the cores from the "black and white coils" and could reinsert them if needed. The motor in my old YouTube video (http://www.youtube.com/watch?v=MEEjlYvZ5OM) has the "black coils" with the cores still in place. Also my "ring magnet spinner" features the "black coils" with cores, see e.g. http://www.overunity.com/11350/confirming-the-delayed-lenz-effect/msg359314/#msg359314

I will order the two relay types indicated, 10 each, the loss will not be overly high in case of problems. I can break four and still have six.

Greetings, Conrad