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Hi guys,

I got a question regarding the ultimainboard (ultimaker 2 electronics) i want to control the small 5v fan with pwm instead of always being on, but which connection can i take for this, if there's any left?

So i'm looking for a 5v output with pwm signal.

Thanks in advance :)

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On mainboard rev. 2.1.4 it is controlled via a transistor connected to the atmega pin PJ6 (integrated in the circuit).

On rev. 2.1.1 it is directly connected to 5v without any way to control it.

If you have the old revision and if you are keen on modifying the firmware and a little soldering you can buy a BC817, a 1k resistor and a diode (a small 1n4148 or similar will do), and build a little pin driver (just like the one for the cooling fans and LED stripes) and move the fan ground to the transistor and connect everything (for easy access) to pin 3 of the EXP3 header (which is the atmega PB7 pin, which is PWM capable).

You should not directly connect the fan to PB7 as it would exceed the power delivery capabilities of that pin (the fan can easily draw 100mA which is way to much for any atmega pin).

Edited by Guest

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Changed my version 2.1.1 board today with the electronics used in de the 2.1.4 version. Now I have a silent Ultimaker 2 while not printing!

Changed the firmware:

Fan on at 40C (EXTRUDER_AUTO_FAN_TEMPERATURE) and turn off at 35C. Otherwise at cooldown around 40C fan goes off and on. Now a hysteresis.....

See you,


Edited by Guest

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