Noctua fan RPM Crazy number's

[matej1006]

Hello

i am seeing on my printer before i press HOME ALL my Fan Rpm is around 1500. when i press home and my printer home them self my Fan Rpm readings are all but normal from 20000 up to 100000 steps around 15000 up.

What could be wrong:

Here is part of code for Noctua fan's

;Water temp
M308 S5 P"e0temp" Y"thermistor" T10000 B10000 A"Water temp."                  ;configure sensor 5 as thermistor on pin e1temp
                                                         
; Water colling NOCTUA FAN'S
M950 F1 C"!duex.fan7+exp.pb6" Q30000 							; fan 0 is a 4-wire PWM fan so invert it, use high PWM frequency, tacho connected to PB6 on expansion connector
M106 P1 H5 I1 T20:25 L125                                       ; set fan 0 value. Thermostatic control is turned on

; Water colling PUMP
M950 F2 C"!Fan0" Q30000 										; fan 2 is a 4-wire PWM fan so invert it, use high PWM frequency, tacho connected to PB6 on expansion connector
M106 P2 H5 I1 T20:25 L255                                       ; set fan 2 value. Thermostatic control is turned on

[A Former User]

3 wire fan, 4 wire fan?

[matej1006]

sorry i missed that is 4 wire

i have 3 fan's connected to one fan output but only from one tacho wire.

[matej1006]

also i just found that when i put mouse over symbol for FAN RPM write Fan0

[Phaedrux]

Can you provide the results of M115 please?

[dc42]

Do you have the fan wires running in the same bundle as the wires to a stepper motor?

[achrn]

30kHz is outside Noctua's spec for the PWM - it's nominal 25 kHz, and Noctuas documentation says "acceptable range 21kHz to 28kHz". I admit, however, that I'd expect 30kHz to work.

[matej1006]

Hello
i will provide M115 results just that i will be home
no in bundle is no wire's for stepper motor noctua in same bundle is just power for water pump

and 30kHz or 25kHz what i had before set in no different

[dc42]

M950 F1 C"!duex.fan7+exp.pb6" Q30000

Try this instead, note the added ^ character:

M950 F1 C"!duex.fan7+^exp.pb6" Q25000

If that doesn't work then I suggest you try connecting a pullup resistor of between 1K and 5K between pin exp.pb6 and +3.3V.

[matej1006]

@dc42 Thanks i will try

[matej1006]

i try all change code, add pullup resistor i remove wire from bundel change all just that show Fan0 where i place mouse over Fan RPM instead of fan7

[dc42]

@matej1006 said in Noctua fan RPM Crazy number's:

all just that show Fan0 where i place mouse over Fan RPM instead of fan7

I'm sorry, I don't understand - please explain what you mean.

[matej1006]

that why is Fan0

if i have Fan0 for colling filament