Hey there! So I've been playing around with this fan module built for the X46YM and have finally figured out the positive and ground wires after dissecting one (turned out that the module has dual fans and each one has their own positive and ground.) Here's some pictures of it and a diagram I made (there is supposed to be a blue wire connected to the empty joint on each fan. It broke off. The blue wire is still shown in the pictures though, just detached):

The thing is, this module has dual fans and each of them have 5 wires: red/red-white, black/black-white, yellow/yellow-white, green/grey-white, and blue (which is actually shared between the two fans.) I've never heard off a 5-wire fan before so I tried to research "5-wire fans" with virtually no info. I also tried to research the chassis model that the fan belongs to (x46ym) as well as every other number I could find printed on the module's chassis (mfg# 72160, r80j12bs1nc-07a02, 3617d n1, cn-0x46ym-72160-36h-11ia) also with very little relevant info (only comes up with refurbished resales.) Poking around at the wires with a multimeter, I figured out that the resistance between the yellow and red is around 30 MΩ, between the green/grey-white and red is around 70 kΩ, and between the blue and any other wire, there is no continuity at all. Therefore, I can conclude that the yellow/yellow-white and green/grey-white wires are the pwm and speed control. All I can't figure out is what the blue wire is for and why it's shared between the two fans.

If anyone has any info on this, it would be a great help. I have a box of about 75 of them and I want to sell them off with the pinout details so that even people without bladecenter servers can find uses for them.

 

BTW, these fan modules blow like CRAZY! They're rated at 12v 5A, though idk if that's the rating for both fans together or if each one only utilizes 2.5A.

 

The question is at the bottom of the first post. Sorry for the bad formatting.

 

5 wires- At a minimum you need power, ground, and return pulse wire. Normally, the blue wire returns a pulse. This is how they tell how fast a fan is spinning, because it uses a Hall sensor to generate a pulse once for every revolution. The other wires, may be (and are likely) related to temperature-- say for monitor inlet and outlet temperature, which would let them know if they need to increase/decrease fan speed.

I find it odd that they tied the blue wire together, unless they don't care about specific RPM, but rather simply care about whether or not the fan is spinning at all.

It's easy to test the blue wire- connect it to an oscilloscope and spin the fan and see if you get a pulse on every revolution. You can do the same with each other wire individually and place one side or the other of the fan near heat and see if you get a rising voltage signal-- this would answer the temp-sensor issue.

 

Oh wow never thought of trying that! Thanks!

 

AC fans with tach outputs have three extra wires, tach power, tach output, and signal gnd. Since these are DC fans ...

My guess is that the three extra wires are a speed control input signal, a tach pulse output signal, and a ground for the signal set that is separate from the ground for the motor. Servers like variable speed fans to meet acoustic noise requirements, and they are paranoid about cooling so there always is either a tach output or a pre-digested fan fail output. As of 2015, Dell FX blade server monitors could show the speed of every fan in the box. Servers also frequently have a separate fan power output from the supply system to isolate motor noise from the rest of the system.

I have no clue what a X46YM is, mainly because you provided no clues. Who makes the server the fans are used in, and who makes the fans? What are the voltage and current statements on the fan hub?

ak

 

This is a Dell fan, for a PE-M1000E 10u Blade server. Fan Model: X46YM Fans are hot-swappable.

Okay, here is likely the layout. I just down know what the green/grey-white is, unless it's a thermal sensor return. I'd check it for an analog output. Or it's for indicating fan removal/insertion...? Not sure.

Wire-Color      Purpose
-----------------------------------------
RED             +12VDC
BLACK           GROUND
GREEN           ?
BLUE            PWM control
YELLOW          RPM return (Hall Sensor)

Hope this helps.

 

Thanks everyone for the input! Like BobaMosfet said, the server model is PE-M1000E 10u and is made by Dell. The voltage rating is 12v DC and the amperage rating is 5A across the module.

In terms of the green/grey-white wire, I don't think its for removal/insertion sensing because I can run the module without it. It may be a thermal sensor return, but again, I feel like the module wouldn't run at all without power going to it if that were the case. I'll try tieing it to the gnd or positive wire and see if that causes the module to shut off. If it shorts, that ok because I got at least 50 more.

The modules might actually be powerful enough to convert to a small leaf blower! Or maybe a heat gun. I'll probably try it sometime.

I really wish my oscilloscope still worked! If I can fix it, I'll try to test the green/grey-white wire. I'm actually worried the yolk on the crt might be damaged. :/

 

Thanks everyone for the input! Like BobaMosfet said, the server model is PE-M1000E 10u and is made by Dell. The voltage rating is 12v DC and the amperage rating is 5A across the module.

In terms of the green/grey-white wire, I don't think its for removal/insertion sensing because I can run the module without it. It may be a thermal sensor return, but again, I feel like the module wouldn't run at all without power going to it if that were the case. I'll try tieing it to the gnd or positive wire and see if that causes the module to shut off. If it shorts, that ok because I got at least 50 more.

The modules might actually be powerful enough to convert to a small leaf blower! Or maybe a heat gun. I'll probably try it sometime.

I really wish my oscilloscope still worked! If I can fix it, I'll try to test the green/grey-white wire. I'm actually worried the yolk on the crt might be damaged. :/

So does it work? does it spin just hookec 12 and ground?