Power an 8.4v Fan from Variable speed fan header?



  • Is it possible to control a 8.4v fan? Can I specify a current output to match 8.4v from my native 24v?

    I think I can drop a 12v line to the 8.4v with a 35.7kOhm resistor but that is static, not varying.

    The RC industry has very impressive 8.4v 30mm fans but Say they run loud.

    I am building a machine to print a range of stuff and want to control the fan speed to be at 5v for low temp filaments, but control it as needed for high temp materials (PC, and Peek will be printed on the machine)

    Or should I just run it off of 5v and call it good?

    Fan for reference is Linked here

    Note, the machine isn't built yet so I cannot confirm if this off of 5v will be enough air or not but would like to set it up if it is possible.



  • @Fickert said in Power an 8.4v Fan from Variable speed fan header?:

    Is it possible to control a 8.4v fan? Can I specify a current output to match 8.4v from my native 24v?

    Yes and no? You can chop the 24 volt output and get 8.4v average, but it'll still be 24v pulses so odds are it'll fry any driver electronics in the fan.

    Easiest is to get a DC-DC converter to create a positive 8.4v output and use the switched ground from the fan output. It's described in detail in the wiki


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