Microprocessor Control

5.3.2 SETPOINTS

Selecting SETPOINTS from the Main Menu will reveal the following menu items:

Table 21 Setpoint functions, default values and allowable ranges

Menu Item

Function

Default

Range

 

 

 

 

MIN TEMP SP *

Minimum room temperature setpoint

72 (22)

50-80 (10-27)

 

 

 

 

HI AIR TEMP

High room air temperature alarm

80 (27)

35 to 95 (2-35)

 

 

 

 

LO AIR TEMP

Low room air temperature alarm

55 (13)

35 to 95 (2-35)

 

 

 

 

* For optimal cooling performance, the minimum temperature setpoint should be at least 1-2° below the expected temperature at the remote sensor, which may require additional consideration of the remote sensor location or minimum temperature setting. If the minimum temperature setpoint is set above the typical remote temperature sensor reading, this will reduce the Liebert XD cooling output and, in extreme cases, cause erratic Liebert XD performance.

To reach the SETPOINTS menu:

1.Press the MENU button.

2.Press ENTER when the SETPOINTS menu is displayed.

3.Use the up and down arrow keys to move through the menu and view the setpoints.

To change a setpoint, follow the steps above, then:

1.Press the ENTER key to change a setpoint. (The control will ask for a setpoint password if passwords are enabled. Use the up and down arrow keys and ENTER key to enter the three-digit password when prompted.)

2.Use the up and down arrow keys to change the setpoint.

3.Then, press ENTER to accept the new setpoint. When finished, press the ESC key two to three times to return to the main display.

NOTE

Setpoints and system setup parameters are kept in non-volatile memory.

The user setpoints and ranges are:

MIN TEMP SP

This setpoint is used to keep the room temperature above the setpoint. The Liebert XDC can lower the room temperature too much depending on the room dew point and load. This setpoint will back off the cooling to keep the room temperature above this temperature, see 5.3.1 - Viewing or Changing Settings.

NOTE

This is not a true room temperature setpoint. The Liebert XDC will try to cool as much as possible. If it is able to cool the room to this setpoint, it will back off its cooling capability to try to keep the room temperature at or above this setpoint, but the Liebert XDC has no heaters, so it cannot warm the room.

HI AIR TEMP

This is the temperature at which the HIGH REMOTE TEMP and HIGH LOCAL TEMP alarms will be activated, see 5.3.1 - Viewing or Changing Settings.

LO AIR TEMP

This is the temperature at which the LOW REMOTE TEMP and LOW LOCAL TEMP alarms will be activated, see 5.3.1 - Viewing or Changing Settings.

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Liebert XDC Setpoints, MIN Temp SP, HI AIR Temp, LO AIR Temp, Setpoint functions, default values and allowable ranges