duex5 PWM/servo pins as parts cooling fan help
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I need to use the servo pins on the duex5 to control the parts cooling fan. the fan is going to be a 5V since the PWM pin seems to only provide 5v. F3-7 are fans to cool the extruder so PWN1-5 will be what i plan on using as parts cooling fan for each tool. if I use PWM1 for example to do this, do I add this in config.g?
M950 H2 C"nil" ; disable heater 2 and free up the associated pin. H2 is heater for Tool 0.
M950 P0 C"PWM1" ; P0 assigned to PWM1 pindoes that mean "P0" is the parts cooling fan from now on?
Another question is the fan i have are 2 wires. the PWM connector has 3 terminals. which pins do I use? I assume GND is required but does the positive go to 5V or to PWM?
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@tekstyle If you use the PWM pins on the Duex, you can't use the associated heater pin, and vice versa; eg if you use PWM1, you can't use E2 heater. So why not use the heater connection, and use a VIN fan? 5V fans are not ideal, as it's easier to short VIN to 5V if connected incorrectly. It's why there's no 5V fan support on Duet 3.
Ian
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@droftarts said in duex5 PWM/servo pins as parts cooling fan help:
@tekstyle If you use the PWM pins on the Duex, you can't use the associated heater pin, and vice versa; eg if you use PWM1, you can't use E2 heater. So why not use the heater connection, and use a VIN fan? 5V fans are not ideal, as it's easier to short VIN to 5V if connected incorrectly. It's why there's no 5V fan support on Duet 3.
Ian
Yea, I figured out not too long ago what it meant by pwm and heater pin sharing the same channel and that it is either or no matter what you do.
I wanted an alternative to using the fan output because I am building an IDEX with 5 tools corexy and my design has 2 fans for each tool, parts cooling fan and extruder fan. I knew I was going to use up 5 fan output for the extruder so I needed another set of 5 output. Duex5 gives me 5 I think and duet2 only gives me 3 output total 8.
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@tekstyle Maybe mount the part cooling fan on the carriage? Would simplify the wiring, and the tool as well. Or switch to Duet 3!
Ian
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@droftarts said in duex5 PWM/servo pins as parts cooling fan help:
@tekstyle Maybe mount the part cooling fan on the carriage? Would simplify the wiring, and the tool as well. Or switch to Duet 3!
Ian
That's how I originally designed it but it got in the way with a revision. I think I figured out a way. Planning on putting a mini microswitch on each tool that will trigger when tool is picked up by the carriage. Once triggered, it will close the circuit to the fan. As long as every other tool's microswitch is in the open state, the fan output will only drive a single fan at a time.
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@tekstyle So all the tool fans will be wired in parallel? Exciting!
Ian
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@droftarts said in duex5 PWM/servo pins as parts cooling fan help:
@tekstyle So all the tool fans will be wired in parallel? Exciting!
Ian
all the parts fan in parallel. its a lot of wiring. hopefully it works. tool fans are all to their own fan output