Window Motor Doubles Voltage At The Power Supply [Overunity ?]

[powercat]

Vid from DadHav / John
http://www.youtube.com/watch?v=xBpir5azwTo
When the power from the bridge rectifiers are switched onto the input, the motor increases speed and the voltage on the power supply readout doubles. I am not claiming this is over unity but I don't know how to explain what is going on. If you have any ideas chime in.
John.

[patmac]

@powercat

Good work your motor looks very nice....

You can put a amp meter between power supply and the motor, then when you switch on to send energy to the source this amp meter must to show negative current.

Good Luck.

[gyulasun]

Vid from DadHav / John
http://www.youtube.com/watch?v=xBpir5azwTo
When the power from the bridge rectifiers are switched onto the input, the motor increases speed and the voltage on the power supply readout doubles. I am not claiming this is over unity but I don't know how to explain what is going on. If you have any ideas chime in.
John.

Hi John,

MAybe two possibilites:

1) I think your motor setup and the power supply becomes an oscillator when you switch the diode bridge feedback on.  If you could hook up an oscilloscope to the DC output of the power supply, you would see oscillations on the DC level line when the feedback switch is on. IF you cannot see any oscillations, then next use the scope AC coupled instead of the previous DC to be able to switch to more sensitive input ranges.

2) Well, if you cannot see any oscillations during the feedback, then the explanation may be in the power supply's inside circuit: somehow it measures the voltage that gets added to its output like in your case the diode bridge surely have an additional 20-21V output over the supply output and the meter circuit inside senses this.  It should not but it may do in this case.

The best test would be you load the diode bridge output with an independent load resistor and changing its value for the optimum power match, compare the input power consumed by the motor (and the H bridge) to that of dissipated in the load. This way you can see you are under or over unity.

rgds, Gyula

[powercat]

Hmmm first of all I am not John
I did point this out in my first post     Vid from DadHav / John
and the writing underneath the Vid that I posted was from his YouTube video description.
My apologies for any confusion caused.
cat

[gyulasun]

Ok cat,  sorry for my misunderstanding.

rgds, Gyula