Emerson Liebert iCOM Manual De Usuario

Outdoor Sensor Sharing
When multiple cooling units with Liebert iCOM and Liebert Air Economizer are networked, the 

control can be set up to share the outside air sensors of all the units connected in the U2U group. 

Outdoor air sensor sharing is enabled on SA16. When set to Shared, all the outdoor temperature and 

humidity readings are averaged among all connected units. The average calculation is used to 

determine air economizer eligibility on lines SA04 through SA06. 
Upon startup after a loss of power to the Liebert iCOM control board, the main fan will operate at 

100% for 5 minutes. After the fan has run at 100% for 5 minutes, the standard fan control will be able 

to modulate the fan. For other control modes, refer to Variable Speed Fans—EC or Variable 

The Liebert Air Economizer can be disabled using a hard-wired deactivation switch, through the 

iCOM display, or through a remote monitoring system using a Liebert IntelliSlot

®

 card. 

A field-installed and wired normally closed deactivation switch may be connected to Terminals 24 and 

51 in place of the factory-supplied jumper. Removing a factory-installed jumper will deactivate the 

unit’s air economizer function (see Figure 41) and produces an FC Lockout warning. A normally open 

deactivation switch may also be used. Line S227 of the Service Menu > Set Alarms must be changed 

from Opened to Closed.
The Liebert Air Economizer may be disabled by changing SA02 Enable Economizer to No. 
The Liebert Air Economizer may be disabled through a remote monitoring system by writing a 

disable command to data label Air Economizer Control. When disabled, SA02 status will read No. The 

building management system may override SA04 through SA07 by writing an enable command. 

When the enable command is written, SA02 will read Remote. Refer to the Liebert IntelliSlot

®

 

Modbus 485, Modbus IP and BACnet IP Reference Guide, SL-28170, for additional information. The 

manual is available at the Liebert Web site: 

Deactivating the Liebert Air Economizer will transfer all cooling to the secondary source.

The K11 relay can be activated when the Liebert iCOM determines that the conditions are acceptable 

for the Liebert Air Economizer

™

 to operate. This relay will remain active during a BMS remote 

deactivation of the Liebert Air Economizer.

24

    

  51

Liebert Air Economizer
Deactivation Switch
Terminals 24 and 51

Factory-Installed Jumper
Customer must remove jumper
and connect normally closed
contact to Terminals 24 and 51.
Open the contact to deactivate
the Liebert Air Economizer
functionality.
Main unit will continue to run without
the Liebert Air Economizer feature.

DPN001449
Pg. 6, Rev. 2