[SOLVED] Wiring colour codes

[sargan]

I have a number of ARCTIC F12 fans .... these have standard 3 pin connector for plugging onto a mobo.

Anyone able to confirm the wiring of these fans as I will not be using with a PC, but a separate PWM controller.

Plug has RED, BLACK & Yellow
I need to confirm which is +V, Gnd and Tacho
Assume it will be the order I listed above - but thought worth checking.

The PWM controller does not have 3 pin plug, it has screw connectors.

 

[dudio]

Look here:

https://allpinouts.org/pinouts/connectors/motherboards/motherboard-cpu-3-pin-fan-connector/

 

[Paperdoc]

Unfortunately, the photo in that link has the positions of the wires wrong, but it IS correct about the colour codes.

Pin #1 - Black - Ground
Pin #2 - Red - +VDC (varies 12 to 5, typically)
Pin #3 - Yellow - pulsed Speed signal from motor back to header

Note that RED is in the MIDDLE, not on either edge.

You can NOT control the speed of a 3-pin fan with a PWM controller, though. The ONLY way to control the speed of a 3-pin fan is by varying the voltage supplied from Pin #2 (red) from 12 VDC (full speed) down to about 5 VDC (min before it stalls and will not re-start unless voltage it raised). A 4-pin fan, and the PWM controller system used with it, gets a fixed 12 VDC from Pin #2 at all times, and uses its own chip with the PWM signal from Pin #4 to modify current flow through the motor windings. If you plug a 3-pin fan into that kind of controller's output, it gets constant 12 VDC from Pin #2 and gets NO PWM signal from pin #4, which it could not use anyway.