Electrical - splicing rpm wire

[amcdonald]

I'm thinking of ways to run an rpm wire to the mboard and the rest to a rheobus.
Here's a few ideas...
Run a Y-splitter off the fan wire and cut yellow off one way, and the red/black off the other (will this work at all like i'm guessing?)
Run this adapter back into a molex to 3-pin adapter, and into the rheobus.
Of these only the second will surely work. but thats a lot of extra wires.

I could splice the rpm into another 3pin connector... but I don't have any of these offhand, plus I'm not sure if that connector needs a crimper or what, I've only messed with molexes.
Any advice?

 

[godmare]

I believe that RPM sensors only operate under 12 volts. Using a rheobus, etc., will cause it to not work.

 

[Drewpy]

RPM wires only work when the fan is connected to ground. This is why the 7V trick messes them up. Take a multimeter to your rheobus, and check that the ground wire is always ground. It should be on a rheobus since they use a variable resistor. If your rheobus uses PWM (pulse width modulation) then the RPM probably won't work.

As for connecting it. I'd cut the red and black wires off the 3 pin connector, and use the bare wires to connect to your rheobus., then just plug the 3 pin into the motherboard header.

 

[amcdonald]

well... I tried it anyway by sticking a rpm wire in between a 3-pin male-female joint, and its working fine.
This is stuck in between the fan and the rheobus.
Its reporting accurate rpm's from low to full voltage.
I just bought a bunch of $0.99 3-pin to molex/seperate rpmwire adapter, ripped the rpm wire off, and replaced it in the chain.
Worked with my corb & ttsmartfan2