Fan Controller Read-Out Fluctuations -- Normal?

[D001]

Hello folks,

I wonder if anyone can tell me whether some fluctuation in the readings on the display of a fan controller is normal.

After I set a voltage dial (or "knob"), the values often fluctuate. For example:

* if I set a dial so that the voltage is "about 8 volts", the voltage typically fluctuates over a range of 7.8 to about 8.2 volts from then onwards.
* if I set all the dials to their maximum, the voltage typically floats over a range of 11.8, 11.9, or 12.0 volts.
* if I set a dial to "around 6.5 volts" the voltage typically fluctuates over a range of about 6.3 volts to 6.7 volts.

And so forth.

Is this normal? I had previously thought that after setting a voltage, it would always stay constant after that point.

I have taken a video here (60 seconds): http://www.youtube.com/watch?v=Vvh-RQ20Ui8 (The video features voltages that are quite low from the range I tend to pick from.)

Any thoughts are most welcome.




PS:

Fan controller: Lamptron FC5 V2 (molex powered) (I have been very happy with this unit overall by the way.)
Power Supply: Corsair AX860 (exhibits "coil whine", sadly)
Fans: 2x Corsair 650D 200mm stock, 1x Corsair SP120 Quiet Edition (standard/non-PWM).

[chuckskull]

Perfectly normal for there to be some variance, just the nature of the motors in the fans. Don't worry about it unless you start seeing big swings in voltage or your fans stop.

[D001]

Thanks again chuck!

[Pob255]

All sorts of things could be causing that, it will depend on where and how the controller is getting that voltage number from.
I'm not so sure about the fans causing it, they should be causing amp variation not voltage, but it could be that those numbers are just estimated voltage based on the knob position.

If you really want to be sure you need to get a multi-meter out and take actual readings

[D001]

Thanks for the tips Pob.