How to add fans to RTPS shells

      How to add fans to RTPS shells

      Hi ya!!

      So, I don't know if this would work for other masks? However I wrote up a quick photo-tutorial for how to add fans specifically to RTPS masks using their existing padding and with no permanent modifications to the shell itself. Click on the link below to check it out!

      Photo Tutorial for Adding Fans to RTPS masks

      Anyway, let me know what you think or if anyone has any questions!! Thanks and take care all!! ^^

      -Afrodyte
      Be YOU!!! The world will adjust. ;)
      Maybe that could be built on so that the fans only turn on when it is sufficiently warm enough?

      I made this little circuit design back in June 2017, with improving battery life in mind; maybe that's a step further to increase the mean time between battery changes? Might be able to stay on a con floor longer. I guess with the convention I attended two days ago, the environmental temperature really worked in my favour.
      Oh nice BritKig!! That's really cool that you made your own circuit to solve your problem, lol!! You must be an EE!! =) I'm always up for trying new things, lol! Though to be honest working on any circuitry is way way above my skill level, lol! See comments about big, blobby soldering!! =)

      So you're using this circuit now?
      Be YOU!!! The world will adjust. ;)
      No, but it's there as a reference design if anyone feels the need for it, be it for LED warning indication, or, in the case and the reason for me linking back to it, for controlling fans! Now that's a breath of fresh air, no? ;)

      Considering logistics, one-off prototypes of this size are not cost-effective. I'd say bulks of 50-100, so what use would I have for the other 49-99, eh?

      Further Reading
      It is simply a heavily-truncated Velleman MK138 with the 14-pin quad-op* LM324 replace with an 8-pin single-op CA3140E and the (clicking) relay replaced with a 2N2222A power transistor (rated at 800mA) to make the circuit totally silent (0dB). The relay and its indicator LED was the reason why Velleman's design only worked properly at one voltage.

      I have simulated this circuit at 4.5v so it should work with your idea because 5-volts is well within the CA3140E chip's operating voltage range and that most of the circuit itself is just potential dividers with variable resistors, which are voltage agnostic (up to certain voltages) and of which voltage fluctuations (due to load switching) should have little impact. I should mention that other op-amps might work if they are pin-for-pin compatible, but might perform less reliably, less accurately or not work at all.

      My design does have one drawback though: no hysteresis functionality to counter rapid-switching when operating close to the designated temperature threshold, which I plan to revise when I get the time (see component R7 in the circuit diagram of this document).

      * Only two of the four available amps were used
      I need to revise the circuit control design, looks like the current incantation is prone to rapidly-switching on and off when the detected temperature (R3) is very close to the threshold (R4 and R5).

      This is the diagram, this one is designed to specifically turn on at ~35C and then turn off when the detected temperature drops to ~30C by having the output "tug" the target temperature about when changing between on and off state.
      revised.png
      Note: Motor (MT1) is just a stress-test placeholder for a 1.5A load and actual loads with what is mentioned in @Afrodyte 's article mentions will be significantly lower than this.

      I'm currently having some teething problems wiring this up as a single-sided* PCB board due to the two extra resistors and additional transistor because I have to get things as low profile as possible, and the main chip pinout isn't making things easier either.

      * Double-sided are considerably more expensive.

      Amari Kig wrote:

      *giggles* looks like a google map to me :D *doesn't understand electronics* lol But having something like that would be useful though, especially during conventions to make sure you don't overheat.

      See this post for a virtual render of it:
      Basic "Heat Safety" Alarm