QU-BD Heated Bed - Second PSU?

I'm finishing up my Prusa i3 build with RAMPS 1.4 and a 225mm x 225mm silicone heated bed from QU-BD. I need to decide on how to power it.

Will I need a relay to power the bed since it's 24v?

How powerful would a single PSU need to be as opposed to two separate ones?

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My (rarely updated) Prusa i3 build log: [3dtheorist.wordpress.com]

Theorist, I would contact the supplier regarding this. They should have first hand knoladge. You can get 24v out of a PC power supply by using a +12 and -12 line. There is a difference of potential of 24v. An analog device like this heater won't care about half of it being -12. I'm not sure how to wire this up though so seek help. You will probably tie one of the two heater wires form the pad to the +12 11 amp positive lug on the RAMPS and the other directly to the -12v line on the supply. You will have to make sure that is a high current -12 line from the supply. You can reference [reprap.org] for help with that.

Again, confirm this with supplier or another reprap user who has messed with 24v on a heater bed. Go into #reprap and you will prob find someone there.

I too have a qu-bd 24v heater with ramps. I havnt setup my ramps or hb yet. Ive planned on using a SSR with a 24volt 16amp psu. I am using a 16.5 amp xbox psu to run the rest of my setup. If anyone has furtyer knowledge of this build it would be gr8 to know as I am new to ramps.

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