Dual power supply

With a RAMPS 1.4 I plan to run dual power supplies, is this possible?

I have an industrial 24v 3.5A and a 12v 3.5A laptop brick power supply.

I do not have a heat bed at the moment, but I plan to upgrade to one once I can get more a power supply with more amps.

I plan to power the electronics and the extruder on the 12v and run the gantry (cartesian robot) on the 24v.

Am I off base? Will these power supplies cut it?

I don't know if it's straightforward to use separate power supplies for the heaters and the motors. Since you don't have a heated bed, you should be able to run everything with the 24V 3.5A power supply. Just make sure that you don't install D1 or you might fry your Arduino Mega board. You will also need to use a lowerhigher resistance on your extruder tip: Around 1.7 4x6.8=27 ohm instead of the usual 6.8 ohm.

Edited 2 time(s). Last edit at 08/24/2011 09:50AM by brnrd.

brnrd Wrote:
-------------------------------------------------------
>You will also need to use a lower
> resistance on your extruder tip: Around 1.7 ohm
> instead of the usual 6.8 ohm.

Lower resistance will draw more power...

24V across 1.7 Ohms will draw over 14 amps

Edited 1 time(s). Last edit at 08/23/2011 03:34AM by NewPerfection.

For twice the voltage you need 4 times the resistance to get the same power, i.e. 27R.

---

[www.hydraraptor.blogspot.com]

Right, I got it backwards.