MKS Gen 1.4 & Thermistors

Good morning!

I have a home made UM2+ which I was running on Ramps1.4/Arduino however I decided to upgrade to a MKS Gen 1.4 as I wanted the 24v input plus the touch screen.  I have got the basics of the printer up and running, using exactly the same firmware that I was using on the Ramps board.  When I go to print, the bed heats up, the auto leveling does as it should but the hotend never gets to full temp.  I have temp set to 215 and it gets up to 208-210 but then doesn't heat any further.  

I have run PID tuning but the temp still jumps around all over the place.  I have PT100 sensors on both the bed and the hotend with E3D amplifiers.  Whatever I try it just wont close yet so far!!  It all worked fine until I bought this board.  

Has anyone experienced similar issues?


  • Check you max pid setting for the extruder. It is possible to limit max. power by setting them to < 255. So in that case go up to 255 and get some more power which leads to higher possible temperatures..
  • Checked the PID setting and it is definitely 255....I didn't think I had changed it.  I wonder if the board is duff....or just not happy with the PT100's.  Temperature does bounce around everywhere
  • Doing a bit more reading, could be the heater itself thats defective.  I only have one 24v heater which came with my Chinese E3D v6 (which I have since upgraded to proper E3D)... Reckon its probably a 25 or 30 w heater so will order a 40w and see how it goes!
  • In host/server temperature graph you see if output is using 100%. If it is your power is just too low. 25W with some cooling of heat zone can really be just enough for pla.
Sign In or Register to comment.