Liebert XDP Setpoints, MIN Temp SP, High CW Temp, HI AIR Temp, LOW AIR Temp, Active Alarms

Microprocessor Control

4.3.2SETPOINTS

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

Table 13 Setpoint functions, default values and allowable ranges

Menu Item	Function	Default, °F (°C)	Range, °F (°C)
MIN TEMP SP	Minimum room temperature setpoint	72 (22)	50-80 (10-27)
HI CW TEMP	High chilled water temperature setpoint	55 (13)	35 to 95 (2-35)
HI AIR TEMP	High room air temperature setpoint	80 (27)	35 to 95 (2-35)
LO AIR TEMP	Low room air temperature setpoint	65 (18)	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.

MIN TEMP SP

Minimum Room Temperature Setpoint—This is used to keep the room temperature above the set- point. The Liebert XDP 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.

NOTE

This is not a true room temperature setpoint. The Liebert XDP has no heaters; it 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.

HIGH CW TEMP

High Chilled Water Temperature Setpoint—There could be many reasons that the chilled water tem- perature is above this setpoint (e.g., chiller problem, control valve failure, etc.) This is the setpoint at which the HIGH CW TEMP alarm will be activated.

HI AIR TEMP

High Room Air Temperature Setpoint—This is the setpoint at which the HIGH REMOTE TEMP and HIGH LOCAL TEMP alarms will be activated.

LOW AIR TEMP

Low Room Air Temperature Setpoint—This is the setpoint at which the LOW REMOTE TEMP and LOW LOCAL TEMP alarms will be activated.

4.3.3STATUS

The user can check the status of the control valve, pump operation, and refrigerant and chilled water temperature.

CONTROL VALVE—0-100% PUMP 1—On/Off

PUMP 2—On/Off

REFRIG T—Refrigerant temperature 0-100° F CW TEMP—Chilled Water temperature 0-100° F

4.3.4ACTIVE ALARMS

This submenu allows the user to review any present alarms. If no alarms are present, the screen will read “No Alarms Present.” If any alarms are occurring, the screen will display “Alarm XX of YY,” followed by the alarm text (“XX” is the reference number of the alarm shown, “YY” is the total number of alarms).

If more than one alarm is present, use the Up or Down arrow keys to scroll through the alarms.

4.3.5ALARM HISTORY

This submenu allows the user to review the 60 most-recent alarms. The first line of the screen will show the alarm number—01 being the newest—and the name of the alarm. The second line of the screen will show the most recent alarm’s date and the time in 24 hour format. Use the Up or Down arrow key to scroll through the alarm history list.

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