Powering Ramps with 12V and Bed with 24V

Waiting for 10 minutes for my Print Bed to be heated each and every time before priting is just driving me crazy. Now I want to upgrade my rig to 24 V. The first step would generally be making ramps compatible with 24V. Buy the new components for Ramps 1.4 that are rated for 24 volts. Then 2 Step would be taking the old components from the ramps board and third step would be to solder the new 24V rated components. This will for sure help me head my Print Bed a lot faster.

But this would take lot of time and effort. The simplest would be to use a Buck converter and a external MOSFET. It would literally cost the same as buying the individual components for ramps. Step down the 24V to 12V and connect it to Ramps and use the external Mosfet to power the Print Bed with 24V.

I searched in the Internet and found many articles on upgrading the Ramps to 24 Volts. Is there any danger on using buck converter and a Mosfet over upgrading ramps to 24 Volts? Or is there any advantages by upgrading Ramps to 24V?

see [reprap.org] for some information


For just 24v bed:
Ramps is already split into 2 power rails.

You plug 24v in the 12v 11amp side, replace the 11amp 16v fuse, plug in a 24v bed and your done.

Just power the 12v 5amp with a 12v supply. Use two supplies, is easyest.

NB a 12v bed and a 24v bed take the same time to heat up!

The normal issue that slows a 12v bed is people have under powered (current) supplies or the voltage is simply not reaching the heated bed (to thin wire to the bed)
With 24v you need less current and thinner wires work fine.

People also seem to forget to insulate under the bed... If you don't insulate your just trying to heat up the room.

If you want a much simpler solution. Use 13.5v on a 12v bed and step that down to for the rest of the ramps.
It doesn't sound like much but it is 12v at 11amps is 132 Watts, 13.5v at 12.27amps is 165.645 Watts

If your trying to plug 24v into a 12v bed... thats going to need lots of current (21.8amp at 24 for a standard 1.1 ohm bed)

Rather than upgrade the RAMPS to 24V I opted to go with separate 12V & 24V supplies and use the RAMPS to switch an external mosfet for my 24V bed. It was straightforward to implement and it meant I could easily control the max current to the bed so as to not exceed the PSU limits during initial heating.