I have an old PSU for an Fanhao D4X printer that has an output of 350 Watts (24 volt / 14.6 amps).
It’s no longer functioning but I do have another PSU that is the same in design except it produces 300 watts (12Volts / 25 Amps) which can be adjusted up to 350 Watts by increasing the voltage by 2.
Although the Wattage is the same will it damage the Wanaho MightyBoard as the voltage and amps are different?
In terms of damage, it’s the voltage that matters most. The voltages must be the same. The power supply with 300w may work just fine, or it may struggle, it depends how much power you printer needs. But the voltages must be the same to avoid damage. Tom
Just to clarify, the old PSU that no longer works was 24V / 14.6 Amps - 350 Watts
The new one that i’m potentially looking at putting in is 12V / 25 amps - 300 Watts, but it can be adjusted up to 14V bringing the Wattage back to 350, like the old PSU.
This new PSU would struggle to provide enough energy as it has half the voltage?
On the contrary, the MightyBoard accepts any voltage input from 12v to 24v. In fact, I’ve yet to see a single 3D Printer board that doesn’t accept 12v, though some don’t like anything above 15v or so.
It’s entirely fine electrically to switch out the power supply to a 12v unit, since the Mightyboard accepts inputs of between 12v and 24v, but the problem may be in your heaters for both your bed and your hotends. Typically hotend heater cartridges dissipate 40W under whatever voltage they’re designed for (though 25W cartridges are also pretty common), so under 24v, the resistance is 24v^2/40W or 14.4 Ohms. Putting 12v through that reduces the power down to 12v^2/14.4 Ohms or just 10W, meaning you’d notice an approximately four-fold increase in heating times. This also goes for the heated bed. Using the same math, your typical 180W heated bed at 24v would be reduced to just 45W at 12v-nowhere near enough to even get the bed to a temperature suitable for ABS, let alone reach it in a timely manner. (Most of the heat would just be dissipated into the air.)
The heater cartridges are pretty easy: just buy a new set of 12v heater cartridges (they’re cheap and most are standard sized). The bed depends a lot on whether or not it’s dual powered, or capable of accepting both 12v and 24v inputs. If it is, then all you would need to do is resolder the bed wires to the proper ones for a 12v input. If not, you’d have to replace the bed entirely, which may not even be possible depending on whether or not a 12v bed exists for your model.
