Page 1 of 1

Ramps Board Running Hot

PostPosted: Wed Aug 28, 2013 5:17 pm
by dave3d
I have more or less completed my Ord Bot build and I am presently held up by my QU-BD extruder playing up. While I am waiting for a new extruder pulley I have been running the printer through some dry runs to fine tune the settings and the calibration.

I noticed the RAMPS board runs very hot and I was thinking of installing a cooling fan. I measured the temps with an infrared thermometer. The stepper drivers vary from 39 deg C for the Z axis (not used much I guess) to 79 deg C for the X axis. However the copper heat sink on the power end of the board read 220 deg C !!!! Anybody fit a fan?

Re: Ramps Board Running Hot

PostPosted: Wed Aug 28, 2013 8:52 pm
by peter_
Hi Dave,

That's normal -- you definitely need a cooling fan that pushes a good amount of air over the Pololu stepper driver heatsinks as well as the MOSFET heatsinks for the heaters/heated build plates for the RAMPS controller to work. If it's not there, (1) the extruder and/or heated build plate may not be able to supply enough current to get up to temperature, (2) the steppers may not have enough current to move the axes, or especially push the filament through the extruder. Almost all the RAMPS cases I've seen include a mount for a very large fan.

best of luck!
Peter

Re: Ramps Board Running Hot

PostPosted: Thu Aug 29, 2013 7:55 pm
by dave3d
i have now fitted a 12v computer fan and it has brought the MOSFET temp down to 160 deg C.

Re: Ramps Board Running Hot

PostPosted: Thu Aug 29, 2013 9:58 pm
by peter_
That still seems warm to me. You might end up needing a fan with a little more air flow. That being said, I'm not sure what the optimum temperature is, but something tells me its well below the boiling point of water. I think I can put my finger on the MOSFETs while they're in use (with the fan, of course) without too much issue.