Fan Controller With Voltage and Temperature Readout




About: I like finding new uses for things, making things, and improving things. I'm a student who is currently looking for a better job, one where I can make an actual difference.

I recently had a computer cd-rom failure and rather than throwing it out, I decided to use its case for a custom fan controller. The fan controller consists of two components, a 10k potentiometer and a NPN transistor. I used a C1984 in place of the npn transistor because I already had it, but any npn should work. The voltmeter and temperature display just need to be connected and mounted in the cd-rom. Both the 4 digit voltmeter and temperature display came from for under $8 free shipping and I already had everything else. I decided to use jst power connectors for the fans because I already had a bunch of them.

Step 1: The Layout and Build

I took out all the internals of the cd-rom drive and used a dremel to cut the openings on the face for the voltmeter and temperature display. I used hot glue to hold them in place, and used more hot glue to hold the jst connectors in place at the back. next I drilled a hole at the front for the potentiometer and mounted it, then used an existing hole to mount the transistor with heatsink to the case using a screw. I taped down some the wires to prevent any strain on them. The layout diagram shows how I connected everything. With the components I used the voltage going to fans can be varied between 7.5-11.5 Volts. I am currently using 4 120mm fans and the transistor warms up but does not get hot, again this will vary based on which npn transistor you decide to use.



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    5 Discussions


    4 years ago

    amazing! I was looking for something like this for a long time! but could you go into more details please as of how you made it?

    2 replies

    Reply 4 years ago on Introduction

    Thanks, sure for the fan controller part of the project its basically two components a general purpose npn transistor and a potentiometer. Its important to use a transistor with a sufficient current rating based on how much your fans need. Also the potentiometer determines the voltage range you will be able to control. The panel mount temp and voltmeter are just connected in as shown in the diagram.