Print FAN0 problem, works as always on?
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Hi all.
I have connected 5V tool fans to FAN1 and FAN2, V for fans is 5V. My print fan is 24V, so I've connected black wire to GND FAN0 and red to VIN 24V. When I set S to 255 - fan is running at full. When I set to 0 - it is still running but half the speed... and can't turn it off. What am I doing wrong? Thanks.
Edit: Duet 2 Wifi v1.04 , firmware latest RC5
Edit 2: So it is working, but like from 50% to 100%
Edit 3: Info about fan: 24V , 0.15A, brushless motor -
As I understand that 1.04 has flyback diodes so the problem not in a failed MOSFET ? Anybody?
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Hi. FAN0, FAN1 and FAN2 have pins VFAN and FAN- . If yours is connected to GND, are you sure it isnt "always on" fan connector?
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@aidar Yes, I am sure that air pump is connected to FAN0- (GND) and other wire(red) to 24V IN. And I can control it through web interface, but when I change the speed to 0% - it is actually seems like 50% at the air pump.
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Hmm...and i bet you dont have L parameter in M106 command. I would try to change PWM frequency, F parameter, as suggested in https://duet3d.dozuki.com/Wiki/Gcode#Section_M106_Fan_On.
Also, thermostatically controlled fans min speed is 0.5, so make sure you didnt config it as thermostatically controlled. -
@aidar This is my setup: M106 P0 S0 I0 F100 H-1 (tried different F up to 25000)
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@dc42 help please. Do I need a flyback diode? (I thought 1.04 board don't need them). Do I need current restrictive thermistor? (But fan is running without problems)
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Type M106 P0 and post the output.
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@sigxcpu said in Print FAN0 problem, works as always on?:
M106 P0
Here is the output: Fan 0 pin: F0, frequency: 100Hz, speed: 0%, min: 10%, max: 100%, blip: 0.10, inverted: no
As I understand you have found my error? min: 10% ? How do I set it to 0% and where it was set as I don't have limits in my config.g
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Set it to 0 with L parameter : Fan 0 pin: F0, frequency: 100Hz, speed: 0%, min: 0%, max: 100%, blip: 0.10, inverted: no
Still spinning and fast enough...
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Info about fan: 24V , 0.15A, brushless motor
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Ok, have found a problem. I have 5V FAN1, FAN2 and always-on fan + 24V brushless air pump. So I need to change V_FAN to 24V and use a convertor for my 5V fans or find source of 5V because(as I assume) of flyback diode.
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@briskspirit said in Print FAN0 problem, works as always on?:
Ok, have found a problem. I have 5V FAN1, FAN2 and always-on fan + 24V brushless air pump. So I need to change V_FAN to 24V and use a convertor for my 5V fans or find source of 5V because(as I assume) of flyback diode.
That's right. When using controlled fans/pumps that take different voltages, V_FAN must be the highest one, otherwise the flyback diodes will conduct.