5v vs 12v fans and the Rambo connection

[LorenOlepi]

I ordered up some 5v 25mm fans and some 12v 40mm fans to do some side by side comparsions for the hot end but got some questions about connecting the 5v fans...
Is there away to control the voltage coming out fan outputs via software? I measured the voltage coming out of the fan output and got 12v and I'm assuming that's because I got 12v going to the mosfets input on the board which I need for the extruders heat. I was hoping there would be a setting in EEProm but didn't see one.

Any help would be appreciated..

[Polygonhell]

I ordered up some 5v 25mm fans and some 12v 40mm fans to do some side by side comparsions for the hot end but got some questions about connecting the 5v fans...
Is there away to control the voltage coming out fan outputs via software? I measured the voltage coming out of the fan output and got 12v and I'm assuming that's because I got 12v going to the mosfets input on the board which I need for the extruders heat. I was hoping there would be a setting in EEProm but didn't see one.

Any help would be appreciated..

No the Mosfet is 12V out, the outputs use PWM to reduce the speed, you might get away with reducing the maximum PWM value either in the firmware or in the Slicer for the fans and putting a reasonably large capacitor across the power pins.

[foshon]

I ordered up some 5v 25mm fans and some 12v 40mm fans to do some side by side comparsions for the hot end but got some questions about connecting the 5v fans...
Is there away to control the voltage coming out fan outputs via software? I measured the voltage coming out of the fan output and got 12v and I'm assuming that's because I got 12v going to the mosfets input on the board which I need for the extruders heat. I was hoping there would be a setting in EEProm but didn't see one.

Any help would be appreciated..

If your using the original power supply just hook it to the red wire for the test.

[LorenOlepi]

[quote="foshon"

If your using the original power supply just hook it to the red wire for the test.[/quote]

Thats what I'm going to do...just stinks that they will be on full blast all the time

[foshon]

[quote="foshon"

If your using the original power supply just hook it to the red wire for the test.

Thats what I'm going to do...just stinks that they will be on full blast all the time[/quote]


Yeah. If you determine the the 5v is the way to go you can regulate via PWM like was suggested or make a little voltage converter.