Lulzbot/E3D Toolhead heatsink fan speed problems
redalenca last edited by
So I recently tore the rambo out of my TAZ 5 and I've replaced it with the Duet2 WIFI. Overall this has been pretty great (the noise reduction is sublime) but taken some finagling to get right. The problem I haven't been able to figure out is how to properly control the heatsink cooling fans on the hotend. I have them all connected correctly but I can't seem to accurately control the speed. When I take the fans on the lulzbot aerostruder or on the HS 0.8 toolhead (essentially titan aero extruders) and set them to 100% they blow like freaking crazy. Like these fans sound like they are coming from the back of a fighter jet. There's turbulence all around the extrusion zone and I can hear it from the next room over. When I turn the fans to 99% they hardly blow enough to even move. I can feel the heat creep up the extruder and I'm just waiting for the extruders to jam super bad. If I go any lower than about 90% the fans won't even move. Is this a settings problem or is this just how these fans work? The only 2 controls I see is speed and frequency, I have the speed at 99 or 100 percent and the frequency @ 500Hz.
zapta last edited by
Some fans don't respond well to PWM. See the thread here https://forum.duet3d.com/topic/13936/how-to-limit-the-speed-of-the-hot-end-heatsink-fan?_=1587447391085
I connected 3 diodes in series with the fan to reduce the voltage from 12v to 10v.
No problem though with my material cooling turbo fan, it response well to PWM.
deckingman last edited by
@redalenca Also check that the vfan jumpers are set to match the voltage required for the fans.
Try lower PWM frequencies. You may need to go as low as 80Hz. If that doesn't work, you can reduce the fan voltage as @zapta suggested. And yes, check that you are supplying the correct voltage to the fan.