Liebert Extreme Density Chiller XDC - Manual (Page 44)

Microprocessor Control
38
5.3.2 SETPOINTS
Selecting SETPOINTS from the Main Menu will reveal the following menu items:
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.
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.
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.
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.
NOTE
Setpoints and system setup parameters are kept in non-volatile memory.
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.