Geeetech

Hello everyone,,
So i just bought a Geeetech i3 Pro B and finally finished building it, only to do a test run on the heaters to check if they were working, the extruder worked a charm however the heat bead( MK2a) i was heating to 50 degrees, at about 45 the mosfet started smoking... so disconnected, and now the mosfet just constantly supplies current, and everytime i connect the heat bed same thing. I've done some reasearch and its because my heat bed has only .8ohms resistance and not 1.3-2ohms causing nearly 15.5 amps to run through the mosfet hence burning out. Now i bought it on ebay, and have requested to have the Sanguinololu board and the heat bed replaced ( the seller just imports them... so hopefully he says yes, others wise i have to pull it all apart and send it back). Now question http://tradevenue.se/ is, when/ if i get an new board and heat bed, how do i stop this from happening, in case the heat bed still has low resistance around the 1 ohm mark?

I'm only new to 3d printers, and really want to get this working, i have had a few other issues related to firmware, and getting it to work on mac and also arduino but i'm slowly getting there...
if someone could please help!

Hi, at present, the motherboard corresponding to PRO B models is the motherboard of GT2560 A +.
If the resistance of the hotbed is too small, printing may be affected.

When you change the hotbed, you can first measure the resistance of the hotbed. It's about 1 ohm.