Fan speed control w/ tach sensor and LabView

[gronk]

Hello,

I have acquired a Delta FFB1212EH fan with a tach output and have an Agilent n6705B power analyzer lying around. I want to use Labview to control the fan speed, but am unsure how exactly to go about this. I have the drivers, and can control the voltage easy enough. But I am having trouble understanding the concept of how the tach sensor outputs information and how I can utilize it to control speed .Also, would the tach output go into a digital port on the power analyzer?

Are there any easy references I can start off with? Any help I could get would be greatly appreciated. Thanks.

- Rob

[CCornish]

The tach sensor outputs may be RPM -> Voltage.

So, for example,  if the fan is spinning at 500 RPM the sensor would output .5V.

This may or may not be how the tach output on the fan you have functions; you will ned to verify that.

If this is the case, you can monitor the voltage at the tach output, scale it accordingly, and use it as part of a control loop to control the fan speed.