Question about controlling a PWM fan.

[gw3d3]

I use this fan to move air over my chamber heating element.

The RPM range is listed as 750-3000RPM and when I start the printer it is on, at full speed. When I look at DWC the fan says that it is at "0" on the slider. When I move the slider to anything other than zero the fan turns off and won't turn back on until I put the slider back to "0". I will post my fans from config.g below.

Is this a wiring issue or did I miss something in my firmware configuration?

Thanks!

; Fans
M950 F0 C"out7" ; create fan #0
M106 P0 C"Part Cooling Fan" S0 L0 X1 B0.1 ; configure fan #0
M950 F1 C"out8" ; create fan #1
M106 P1 C"Hot End Fan" S0 B0.1 H1 T35 ; configure fan #1
M950 F2 C"out4+out4.tach" ; create fan #2
M106 P2 C"Chamber Fan" S0 L0.2 X1 B1 ; configure fan #2

[jay_s_uk]

@gw3d3 if its 4 wire PWM controlled fan , you have to invert the PWM pin https://docs.duet3d.com/en/User_manual/Connecting_hardware/Fans_connecting#firmware-settings

[gw3d3]

@jay_s_uk Oh ok, it is a 4-wire fan. Is the the PWM pin inverted by the "!" sign?

[jay_s_uk]

@gw3d3 yes. see the example at that link i posted
e.g.

M950 F2 C"!out4+out4.tach" ; create fan #2

[gw3d3]

@jay_s_uk So, that did invert the behavior but now anything under 100 is just off.

[jay_s_uk]

@gw3d3 You may need to adjust the Q value on M950

[gw3d3]

@jay_s_uk Thank you, I set the Q value to 25kHz as per Noctua's specs and it is working well now!