Automatically control E3D cooling fan. Azteeg X5 v2.0

[Rick]

Connect the E3d cooling fan to the other fan connector on the Azteeg X5 v2(Fan connector 1, one on the left)

With this simple change to the config.txt you can get the e3d fan to turn on once the hotend gets above 50c. It will also turn the fan off once the temp drops below 50c.

Find the following lines and edit as shown.
1. edit the two lines in the first section
2. un-comment all the temperatureswitch lines as below (remove the '#' from the beginning of each line)
3. edit the temperatureswitch.hotend.threshold_temp value to set the temp you want the fan to come on at.
4. Save the file back to the board and power cycle the board.
5. Enjoy the silence!

Once the board boots up the fan should be off. load up your app of choice and heat up the nozzle and see what happens..
Notice the last two lines, it controls how often the board will check for a temp change. So, on heatup the board only checks the temp every 15 seconds, it may take 15 seconds for the fan to come on after reaching 50c. Also on cooldown the board only checks every 60 seconds so it might take that long to shut it off.

switch.misc.enable                           true             #  <*******  Edit this Line *********>
switch.misc.input_on_command                 M42              #
switch.misc.input_off_command                M43              #
switch.misc.output_pin                       1.25             #  <*******  Edit this Line *********>

# automatically toggle a switch at a specified temperature. Different ones of these may be defined to monitor different temperatures and switch different swithxes
# useful to turn on a fan or water pump to cool the hotend
temperatureswitch.hotend.enable              true             #
temperatureswitch.hotend.designator          T                # first character of the temperature control designator to use as the temperature sensor to monitor     *********************************
temperatureswitch.hotend.switch              misc             # select which switch to use, matches the name of the defined switch *
temperatureswitch.hotend.threshold_temp      50.0             # temperature to turn on (if rising) or off the switch * Un-comment these lines
temperatureswitch.hotend.heatup_poll         15               # poll heatup at 15 sec intervals *
temperatureswitch.hotend.cooldown_poll       60               # poll cooldown at 60 sec intervals *********************************


[scottadams]

I made this tweak too, but chose a lower temperature. I think 28C or so, no particular reason. It works great to keep that crazily loud fan on as little as possible.

But a warning: I found that it doesn't *always* activate on heating up. It would sometimes require the Azteeg to be reset before it worked. So I just added a M42 command to the custom start G-code to turn the fan on before starting to heat for a print. Turning off seems to work reliably and wouldn't hurt anything if it didn't.

In Slic3r Printer Settings, custom start G-code:
M140 S[first_layer_bed_temperature] ; Start heating bed
M42 ; turn on extruder fan
M104 S[first_layer_temperature] ; Start heating nozzle
G28 ; home all axes
... etc

You need to specify the bed and extruder temperatures with the bracketed commands otherwise the fan won't turn on until too late. Repetier runs the custom G-code after it's sent the temperature commands. Specifying them with the brackets overrides that behavior.

[carlos]

This would have been awesome for the v1.1 board.

[Rick]

Mar 25, 2016 4:36:56 GMT scottadams said:

But a warning: I found that it doesn't *always* activate on heating up. It would sometimes require the Azteeg to be reset before it worked. So I just added a M42 command to the custom start G-code to turn the fan on before starting to heat for a print. Turning off seems to work reliably and wouldn't hurt anything if it didn't.

Ok, I figured out what is going on.. If you or or slicer issues a M109 command to set the extruder temp then problem you describe happens. M109 heats and does not return control to the system until it reaches the target temperature. As soon as the command is finished the fan will start up...   If you use the M104 command to heat the extruder(which does not wait) then the fan switch will workas expected.
 
Sounds like a bug in the smoothie firmware.

[Rick]

I just received a reply from Aurthur from Smoothie and it is a bug that they plan to fix.

[scottadams]

Oh good. Glad to know it was a bug and that it's known and planned to be fixed. Thanks for letting us know.

[Rick]

This is finally fixed! Get the latest firmware from the Smoothieware web page.


Enjoy the silence....