Adding an extra NIDEC Fan
Hi All,
Having a bit of trouble configuring a new fan on my 400mm VCORE4 IDEX machine. I want to add a PWM fan to the enclosure wall so I can create negative pressure within the enclosure and vent the fumes out of the house. I did some math (may be incorrect) and want to try the NIDEC fan used for the parts fans as apparently, I only need to run it at 20% during printing to create negative pressure then run it at 100% for a few minutes after the print to completely vent the chamber. I don't know if this will work, not the subject of the post, but wanted to give background.
My question is; how can I add another 12V PWM fan to the printer? I seem to get a PWM signal when I plug in to the 12V power for the existing part fans, but I can't find another 12V source to plug in to on the board, and trying to wire it like in the RatOS guide by pulling 12V +ve from a fan plug and putting the negative wire into HE1 -ve only provides 10V and the fan won't turn on. Any suggestions to put me out of my misery?
Solution:Jump to solution
For those that may come here for the answer, this is the code that I used. I realized that I only needed one enable_pin as PA15 wasn't in use, only the Fan15+ pin for power.
[fan_generic enclosure_fan]
pin: PD14
enable_pin: PA3...
17 Replies
Did you called the PA3 (HE1) pin in the printer.cfg?
Which is already being called in RatOS.cfg btw
This is what I have in my printer.cfg
I have the PWM hooked up to PA8, but have no idea what else to code.
Ignore my # sections, I just copied from the ratOS.cfg, which I recognize is likely a source of my issue.
PA8 is also being used in RatOS.cfg if Iām not in mistake, maybe try to null and call it in printer.cfg
pin: PA8
pwm: true
cycle_time: 0.01
shutdown_value: 0
Only so the exclamation mark if the fan behaves the opposite way, like if you set it to 0 and it turns on and vice-versa, the ! Is used to invert the signal
I had to change that code to hardware_pwm: true as it said pwm: was an invalid command, and I also ditched the shutdown_value for the same reason (and the default is 0 anyway).
Sadly, no love. Still only getting 10.3V across the pos and neg terminals. No activation when I change the PWM % on the ratOS control screen.
Tried changing the pin to PD14 as it dosen't seem to be referenced in the RatOS.cfg, but also no love.
Post a picture how you connected the fan to the mainboard
You need a 12 volt supply for it, the other always-on fan plug can be used, ground to a heater port and PWM signal from a controllable fan port or another heater port.
later edit: just saw you mentiond that it is an IDEX, so most probably, both always-on ports are already used. A solution would be to splice toghether the part cooling fans so that they run from a single port and have the other one free for the third fan. Another would be to use a regular fan port set to 12v but the downside would be that it would run at 100% until klipper starts
Your current config does no contain that the heater port should be turned on when activating the enclosure fan and the PWM part, you are only pulsing the ground pin from the fan plug which is not used since you mentioned that the ground is connected to HE1
I can't get a photo, but this is how it is wired in,
It does pull 10.3V though
The corresponding jumper on the red wire is set to 12V
I do agree that I am missing something, as when I ran power from the top two fan ports (that are running the part fans) I still couldn't get it to start up, though there was a voltage
Give me a few minutes, I'll make a config based on that picture for you to try
[fan_generic enclosure_fan]
pin: PD14
enable_pin: PA3
enable_pin: PD15
cycle_time: 0.00004
hardware_pwm: False
shutdown_speed: 0
give this a try, not sure if it will work with 2 enable_pins, never tried it with 2 different fan ports
I'll give it a go once I get the kids to bed. Can you explain the parts? As I understand, pin: controls the the PWM, while enable_pin: turms on the power?
Exactly
Will it make a difference if I am currently getting a green light behind HE1 while the fan is wired in this configuration?
I'll make sure to take a photo of the board when I go and try your code above.
No difference, from what I know the led shows it is wired
Ok š I'll give it a go shortly and post the result.
You sir are a saint. You have solved the issue I've been struggling with all day.
Solution
For those that may come here for the answer, this is the code that I used. I realized that I only needed one enable_pin as PA15 wasn't in use, only the Fan15+ pin for power.
[fan_generic enclosure_fan]
pin: PD14
enable_pin: PA3
cycle_time: 0.00004
hardware_pwm: False
Awesome, glad it worked