Been runing a RAMPS 1.4 board for about a year but recently run in to trouble, The mosfet controlling the heated bed suddenly started drawing heaps of power enough that it was starting to smoke the wires on the power supply odly though it sort of still worked it would only draw this power when it was turned on in software and the bed still heated up. So I replaced the mosfet and same thing, Lifted the drain pin and checked the current being drawn by the bed about 3 amps, hmmm. Re soldered the the drain and lifted the source to check the current there, turned it on and before I could even check I noticed the mosfet was insanley hot so cleary the issue is one between gate and drain, I would assume this is just a dead mosfet but I have replaced it with 3 known good fets and same issue. I am really lost on this one, any ideas would be really helpfull...
↧