Duet wifi: fans wont stay on

Mklein23 · 12 Feb 2019, 22:09

When I power on my duet, the AO fan turns on as it should and stays on. However the Part cooling fan only turns on for a few seconds then turns off. I can not get it to turn back on with any combinations of M106, or the slider in the machine control.

If I unplug and replug in the duet, the same behavior is observed.

Any ideas?

Phaedrux · 12 Feb 2019, 22:39

Can you post your M106 fan configuration from config.g?

Mklein23 · 13 Feb 2019, 14:24

M106 P0 S0.3 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P1 S1 I0 F500 H1:2 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on
M106 P2 S1 I0 F500 H1:2 T45 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on

I have this fan NF-A4X10-FLX 5V

I did get it to turn on while printing. which means that simplify3d is posting the correct codes for it; but the Slider in the control panel does nothing. Thoughts?

dc42 · 13 Feb 2019, 15:44

What do you mean by the "A0 fan"? Which fan output have you connected the part cooling fan to?

Note our recommendation in https://duet3d.dozuki.com/Wiki/Connecting_and_configuring_fans#Section_Overview:

"Our intention is that in a 3D printer with a single print head, you use the Fan0 output for the print cooling fan and the Fan1 output for the heatsink fan. This is the easiest configuration to use because it's what the firmware expects by default."

Phaedrux · 13 Feb 2019, 16:01

I took it to mean AO as in Always On

Phaedrux · 13 Feb 2019, 16:04

@mklein23 said in Duet wifi: fans wont stay on:

I have this fan NF-A4X10-FLX 5V
I did get it to turn on while printin

That's a 5v fan? Do you have the v fan jumper set to 5v and all your other fans 5v?

Mklein23 · 13 Feb 2019, 21:27

AO is what I meant be always on fan.

It appears that the jumper is on the V-in Pins. Which means that the part fan is getting a full 12V instead of the rated 5V. Will this impact the board at all? not too concerned about the fan... Is that fan controlled by PWM? The fan looks like it's just a DC based off of the amazon listing so if I run it at 40% would that be just shy of 5 volts or is it controlled via PWM?

I'll look into getting a 40mm 12v fan in the mean time. I just happened to have this fan lying around at the time.

EDIT: looks like noctua makes a 5v and 12v variant of that same fan. Ill buy the 12v version.

Phaedrux · 13 Feb 2019, 22:21

@mklein23 said in Duet wifi: fans wont stay on:

EDIT: looks like noctua makes a 5v and 12v variant of that same fan. Ill buy the 12v version.

Definitely the way to go. Using PWM to undervolt is not a good way to operate because the fan won't be getting 5v it will be getting 12v 40% of the time. It might not damage the board but it won't be good for the fan.