Working principle of the AirLull^®

The AirLull is a 19" rack mounted 1U device and has a “shortcut tube” in which three sensors are measuring the temperature. Between sensors 2 and 3 a heat resistor generates a very low heat dissipation. Sensor 1 is used for calibration purposes. The pictures below show the design of the AirLull and explain how it works. The AirLull knows 3 different situations:

1. Air flow from the front to the back

TT2 < TT3
This means that the temperature measured by sensor 2 is lower comparing to the temperature as measured by sensor 3. And thus air is flowing from the front to the back. In this situation the color indicators of the AirLull will appear blue.



2. No air flow

TT2 = TT3
This means that the temperature measured by sensor 2 is equal to the temperature asmeasured by sensor 3. And thus no air is flowing. In this situation the color indicators of the AirLull will appear green.

3. Air flow from the back to the front

TT2 > TT3
This means that the temperature measured by sensor 2 is higher comparing to the temperature as measured by sensor 3. And thus air is flowing from the back to the front. In this situation the color indicators of the AirLull will appear red.