Emerson 3000/ITR Benutzerhandbuch

The Liebert iCOM will audibly and visually annunciate all enabled alarms. Alarms are wired from 

Terminal 24 through a normally open contact to locations 50, 51, 55 and 56, respectively, for alarms 1 

through 4. 
The alarms can be delayed from 0 to 255 seconds.
The alarms can be designated as WARNING, URGENT, or DISABLED. Alarms designated as 

WARNINGS are annunciated after the Time Delay, but do not energize the Common Alarm Relay. If 

designated as URGENT, they are annunciated after the Time Delay as a WARNING alarm and then 

re-annunciated after a user programmable period from 0 minutes to 999 hours as an URGENT alarm. 

When annunciated as an URGENT alarm, the Common Alarm Relay is activated. 
When a new alarm occurs, it is displayed on the screen and the audible alarm is activated. If the Lie-

bert Challenger 3000/Liebert Challenger ITR with iCOM is communicating with a Liebert site moni-

toring product, the alarm is also transmitted. The display will also show a message to “PRESS 

ENTER KEY TO SILENCE” the alarm. After the alarm is silenced, the display will return to the Nor-

mal Status Display. 
The alarms can also be silenced through communications with a Liebert site monitoring unit. Most 

alarms will reset automatically when the alarm condition is no longer present and only after it has 

been acknowledged by being “Silenced.” The exceptions are:

• The three software alarms: Loss of Power, Low Suction Pressure, and Short Cycle, which reset 

automatically 90 minutes after being “Silenced” or acknowledged.

• Some alarms, such as overloads and high pressure switches, may require a manual reset depend-

ing on your model. 

An alarms history is retained in nonvolatile memory.

Periodically, the return air filters in the environmental units must be changed. The Change Filter 

alarm notifies the user that filter replacement is necessary. A differential air pressure switch closes 

when the pressure drop across the filters becomes excessive. The switch is adjustable using the proce-

dure on the switch label.

An optional tri-block overload device can be used for the compressor. Compressor overload may be 

manual or automatic reset, depending on your model. Overload is located at the electric connection 

box on the compressor.