Don't get confused with a prusa mk2/mk3 heated bed, as that is a different thing... the prusa heated bed is not square like this one.
This bed is designed to be dual voltage, most are not.
The English is dreadful and misleading.
If you notice the table on the top of the bed. this is a wiring diagram.
For 12v you wire +12 to pin1 and gnd to both pins 2 and pin 3
For 24v you wire +24 to pin 2 and gnd to pin 3.
This works as the headed bed is two resistors
____ ____
Pin3 ____|2R2 |____ Pin1 ____|2R2 |____ Pin2
|____| |____|
When you use 24v connected to pins 2 and 3 the resistors are in series and has a resistance of 4.4 ohms
When you use 12v, the wiring puts the two resistors in parallel resulting is a resistance of 1.1 ohms
You cannot normally put 24v on a 12v bed because it will draw 4 times the current and probably burn out.
4 times the current will probably exceed your power supply current ratings and the current ratings of the driving MOSFETS
Raising the voltage 1-2 volts is often done and helps with heat up times a lot.
Edited 1 time(s). Last edit at 12/19/2019 09:21PM by Dust.