Emerson Liebert iCOM Manual De Usuario

Teamwork Mode 3 can be selected when the units are set to operate in Optimized Aisle Control mode 

and have been connected in a unit-to-unit network. Teamwork provides coordination between the 

units that will prevent “fighting” by not allowing units to operate in conflicting modes of operation at 

the same time by selecting which mode to operate within based on the average of the collective unit 

sensors (Cooling vs. Heating and Humidifying vs. Dehumidifying). For additional details, see 3.9 - 

Liebert Optimized Aisle Control.
Teamwork Mode 3 allows the cooling capacity (Supply Sensor) to operate as a local control by 

removing only the amount of load required to maintain the discharge air temperature at each unit. 

This allows for an unbalanced room load while maintaining a consistent discharge air temperature. 

The fan speed is controlled by the remote rack sensors of all units, providing a controlled delivery 

method of the air to the cold aisle. In raised floor applications, Liebert iCOM units will share sensor 

information to achieve even under-floor air distribution. This distribution is achieved by operating all 

fans in parallel, which will also yield the greatest energy efficiency.
Figure 65 shows the difference in both under-floor air distribution and energy consumption when 

Variable Fan speed and Teamwork Mode 3 are applied to the Liebert cooling units. The example on 

the left is using the standard standby configuration; the example on the right is utilizing Teamwork 

Mode 3. The units below are assuming that the fan power consumed at each unit is 8.1kW when 

operating at 100%.

When data center environments require the cooling equipment to modulate from very low loads to the 

full design load, iCOM can coordinate unit capacity and unit activation in accordance with the 

Teamwork Mode 3 operation described above. The Liebert iCOM optimized aisle controlled units that 

are placed into Standby mode will activate as the room environment demands more cooling capacity. 

iCOM will monitor the rack sensors and current operating state of each unit to determine when to 

activate a standby unit. 
To provide the most efficient operation from a system perspective, the Liebert iCOM will first ramp 

the operating units fans and chilled water valve to compensate for the increased heat load. Once the 

operating units have reached a set fan speed, the supply compensation (see Figure 107) may be 

activated to determine if a lower supply temperature can compensate for the load increase. Once the 

supply compensation routine has reached its threshold then the Liebert iCOM will activate a standby 

unit within the group.

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Variable Speed

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Area within dotted lines is 

being cooled by CRAC units 

controlled by Liebert iCOM