M201 hotend fan control

[mark2]

Hi all,
I am using my M201 (firmware 1.0.4) with RepetierHost 1.6.1 and slic3r 1.2.9

So slic3r is setup for auto cooling, but the fan on the hotend never stops. Instead the fan on extruder 2 stop for the first layer, making me think there is a firmware issue here.

The fan to the hotend only has two leads, so presumably is not speed controllable anyway, but should the control gcode generated still attempt to control it, and at least turn it on and off?

The connection of the fan is to the top right of the control board, extruders 1 and 2 go to connectors down by the extruder drivers. Is it possible to tweak the firmware settings to switch the fans around?

Thanks

[Mark]

when control the PWM fans using the manual control in the repetier host, you can only control the default one P0. If you want to control each of them seperately, then you can use the gcode command, for example: "M106 P1 S150" , this means you can set fan P1 to speed 150 (0-255).

Catch3FD5(04-25-15-28-22).jpg (518.52 KiB) Viewed 9879 times

[mark2]

Right. So as per the wiring diagram, the little hotend fan is wired to P4, meaning it is not directly controlled, but P0 goes to one of the extruders.

The little hotend fan is only two wire (power, gnd) so wouldn't be affected by the PWM gcode anyway.

Since in the M201 the extruders are so far away from the hotend there is actually no point in even running the two extruder fans is there? certainly the motors themselves don't need cooling and the filament is at least 30cm from the hotend so doesn't need cooling itself.

Can't I just disconnect these two fans and save some noise?

[Mark]

yes you can, I didn't use them too. But the truth is, the little fan on the hotend is used for cooling down the tube, not for the nozzle/filament when printing, so no need to control it too. And though it only has two wires, it can be controlled by the PWM fan connector too, cause it only use the + and - pins to control the fan, the signal pin is not used.