Print FAN PWM control issue

[elmensy]

Hello all,

I migrated from a F6 board to the S6 board and was testing my functionalities. I encountered an issue in which my print fan is not controlled properly. When controlling the fan via repetier or the LCD, it does not start until I reach 95% of the PWM. In the region from 95-100% the fan just turns on with maximum speed. No PWM change is observed. I did not change any settings (except the correct pin assignment within the S6 fan connections) between the firmware for the F6 board and the S6 board. What can cause this issue?

Below are some specs of my setup:

• Firmware: Marlin 2.1.2.1
• Board supply: 24VDC
• Fan supply/type: 12VDC (also connected the jumpers on the board to 12V)
• Normal PWM mode (i.e. No fast PWM defined)

Please let me know if you need any extra info.

Thanks in advance!

[maralb1970]

I migrated from a F6 to a S6 a long time ago in my Hiprecy Leo printer. I had a similar problem. The S6 PWM frequency for the fans was set to 20kHz. I changed the frequency to 500Hz in the variant.h file to be found in \buildroot\share\platformIO\variants\MARLIN_FYSETC_S6 folder. Not sure if this is the way to do it, it worked for me.

[elmensy]

I migrated from a F6 to a S6 a long time ago in my Hiprecy Leo printer. I had a similar problem. The S6 PWM frequency for the fans was set to 20kHz. I changed the frequency to 500Hz in the variant.h file to be found in \buildroot\share\platformIO\variants\MARLIN_FYSETC_S6 folder. Not sure if this is the way to do it, it worked for me.

This did the trick for me 👍 Dont know if more people encouter this issue and/or if this is typically something for a particular case. Otherwise I guess it should be something to take into account in future releases/updates.

Thx @maralb1970 for the help!