Comments on: Accessing the RPM sensor on a pc fan

By: strider_mt2k

strider_mt2k — Thu, 10 May 2007 06:19:59 +0000

Hey, the folks at Hackaday were humorous and good natured enough to post my stupid string tether for the game boy micro hack, and that was a piece of string!!

They can hang and are open-minded, which is more than I can say for many of you.

By: ScrappyLaptop

ScrappyLaptop — Wed, 02 May 2007 07:47:44 +0000

Hey! I just tried to wire up this LED-thing like you said (“omg we can apply power to these leds and they give light.”). It flashed really bright and then popped & now it won’t light up again -WTF?!?!? That’s a crappy hack if it only works 1x…

On the other hand, I just today discovered that what I thought was a junk box full of old two-wire fans is actually a junk box half full of old two-wire fans and half full of fans with the potential to be three-wire, rpm monitor fans. That made my day. ;)

By: werejag

werejag — Mon, 30 Apr 2007 06:52:11 +0000

@heter

i suspose your right :/ just dont see how its more complicated than wiring up an led

By: heter

heter — Sun, 29 Apr 2007 11:47:34 +0000

@ werejag

im not attacking you, im just saying that to get this feature on most fans you have to either open them up or cut a bit of plastic away to get to the solder pad, to solder a lead that wasn' supposed to be on that model of fan

i do respect your opinion, i just can't see how this is like wiring up an LED ;)

By: Jakeh

Jakeh — Sun, 29 Apr 2007 06:01:03 +0000

@Heter and shadowslayer: Sing it, brothers!

@bking: Uh, yeah, well, I work at Initech and I don't consider myself a pussy, OK?

@egonis: well, you could do that actually. Just program a PIC or something to count the pulses coming out of the wire. Multiply the number of pulses-per-second by 60 and you've got RPM!

By: Egonis

Egonis — Sat, 28 Apr 2007 23:36:08 +0000

I was hoping this was a way to grab the RPM's and use it in our own projects or something.

Wouldn't that be handy? Have a relay trigger a powerdown when the RPM's drop below 1000 or something.

By: werejag

werejag — Sat, 28 Apr 2007 23:21:16 +0000

@heter – this is hack is on par with my led comment. the fan came with the rpm sensor built in. if he told how to add rpm sensor or how to read that rpm sensor that would be a hack worth reading.the fan was designed to do that from the moment you buy it. the wiring is a non issue.

and attacking me because i complain about this is shallow and superficial. i plan to provide a hack soon but its not this add a wire and get on hackaday type.

By: Shadowslayer

Shadowslayer — Sat, 28 Apr 2007 22:12:15 +0000

Come on guys I know we all love the i built the huge complex stuff outta nothing post but this is a legit hack. Did that fan come with the wire No he added it to unlock an unused feature. Sure it was simple but it worked, and now we know that some of these fans we buy with just 2 wires DO have the solder point for the rpm sense wire. This is a useful hack so stop bitching. Even if your one of those guys that built a cellphone outta radioshack parts you still gotta respect this guy for taking the time to look and figure this out. Lets thing before we flame.

By: heter

heter — Sat, 28 Apr 2007 19:17:39 +0000

from answers.com:

hack

[very common]

1. n. Originally, a quick job that produces what is needed, but not well.

this is a quick job that gets RPM monitoring from a fan that didnt originally have the connector for that function.

@ werejag - this is not the same as applying power to an LED. and LED is designed to do that from the moment you buy it, the FAN is not, you have to add the connecter yourself. didnt see you complain about and of the other "add a few wires + connector" hacks

@ atrain, def, wewjag and bking - got a better hack? submit it or post it in the comments. please don't just whine about other people's hacks

By: bking

bking — Sat, 28 Apr 2007 11:01:12 +0000

honestly this hack is for pussies

By: werejag

werejag — Sat, 28 Apr 2007 07:04:20 +0000

next you will how to tell us how to “hack a led”. omg we can apply power to these leds and they give light.

By: Jakeh

Jakeh — Sat, 28 Apr 2007 04:12:10 +0000

I have to say, this is actually the exact type of hack that got me into hack-a-day in the first place. It’s all about unleashing the hidden potential of tech, no matter how simple!

By: m1k30rz

m1k30rz — Sat, 28 Apr 2007 01:26:47 +0000

this hack is from 2003 lolz

By: def

def — Fri, 27 Apr 2007 22:38:39 +0000

This is a shit hack. I read “add your own rpm sensor” – Err fuck off, he just soldered on a wire. You’ve got to be a retard to bother posting this on the net.

By: Stephen

Stephen — Fri, 27 Apr 2007 20:55:32 +0000

I actually just tried doing this the other day with a fan I ripped out of a dead psu. It had only 2 wires, because it didn’t need monitoring in the psu. But, alas it reported 6000 rpm all the time. I might have fried the ic’s while soldering, I suppose.