Adaptive Cooling Technology uses three operating modes:

•In free-air mode, the module uses outside air for equipment cooling.

•In DX assist mode, DX units reclaim exhaust (warm) air to mix and re-circulate with outside air.

•In full DX mode, DX units provide full cooling by re-circulating and dehumidifying all inside air.

Figure 7 shows the airflow of each operating mode and the PUE that each can achieve.

Figure 7: This illustration shows airflow for the HP POD 240a.

ACCA

BB

AFree-air mode air flow

BDX assist mode air flow

C Full DX mode air flow

Adaptive Cooling Technology intelligently adjusts to the most efficient operating mode for maintaining the cooling parameters you set. A typical daily routine would be for the system to use free-air mode in the morning when it is cooler outside, and then automatically switch to DX assist mode as the day gets warmer. In the afternoon when the outside temperature is hottest, the system would switch to Full DX mode. When the weather gets cooler in the evening, Adaptive Cooling reverses the process.

While you can get the best PUE with free-air mode, even full DX mode can yield a PUE of 1.3. That is far better than the 2.0 to 2.4 PUE that traditional facilities try to achieve.

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