Cooling Fan Wiring?

[RogerR]

I have a cooling fan, it works fine on my server rack, but i'm confused. Yesterday I saw sparks from it. I pulled it apart and there is a cooling fan with 3 wires. Red for positive, Black for negative, and a green wire. The red and black are connected so the fan works, but the green doesn't seem to do anything. Any ideas what this could be? Can i cut it?

[B.Maclean]

Sounds to me like the green is a ground wire. I think you could connect it to the case, or the server rack, and the sparking would probably stop. I'm sure someone will correct me if I'm wrong.

[NetworkManager]

But if the black wire is the negative, wouldn't that be the ground wire? Maybe it's some sort of monitoring or control wire?

[B.Maclean]

But if the black wire is the negative, wouldn't that be the ground wire? Maybe it's some sort of monitoring or control wire?

Again, I could be wrong, but my understanding of wiring (mainly from replacing ceiling fixtures) is that there is a "hot" (positive) wire, another main power wire (usually the black), and a ground. I don't know why it is that way, but that seems to be standard.

[DataCenterStaff]

I agree. That's what most setups are.. It's gotta be a ground. Got any pictures? Where is it leading to?