Liebert CHALLENGER 3000, Operation And Maintenance Manual

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Operation with Advanced Microprocessor with Graphics Control
20
3.5 Operating Status
The Operating Status is intended to provide the user with displayed information about what the con-
trol is calling for the system to do.
For example: The display indicates the chilled water valve is 68% open. On a new call for cooling, it
takes several seconds for the valve to travel from full closed to 68% open. So when the display reads
68%, it may take a few seconds for the valve to actually open 68%. Also, if the display indicates a com-
pressor is operating but the compressor has not turned on yet, it may be off because of the short cycle
control (see 4.4.1 - Short Cycle Control ).
3.6 View/Set Control Setpoints
Control setpoints can be reviewed and/or changed through the display. Refer to the following table to
see the list of default setpoints and their allowable ranges.
3.7 System Setup
Selecting SYSTEM SETUP will step to the following menu:
• SETUP OPERATION
• SELECT OPTIONS
• CALIBRATE SENSORS
• CALIBRATE VALVE ACTUATOR
• SELECT CONTROL ALGORITHM (chilled water or SCR Reheats only)
• SELECT HUMIDITY SENSING MODE
• SET STATUS DISPLAY
• CHANGE PASSWORDS
3.7.1 Setup Operation
The SETUP OPERATION menu permits the review and/or adjustment of the unit configuration. This
may include:
Cold Start Delay
This feature, also referred to as Positive Start or Winter Start Kit, allows for the low pressure switch
to be ignored for the programmed time during a cold start of the compressor. Entering a “0” for this
time will bypass this feature. A “1” will bypass the low pressure switch for one minute, a “2” for two
minutes, etc. The programmed value can be from 0 to 3 minutes. This delay is factory set to 0 for
water cooled, glycol cooled, and GLYCOOL units. Typically, only air cooled units need a “Winter
Start” time.
NOTE
There may be some time lapse before a specific component matches the displayed number.
Table 8 Default setpoints and ranges
Setpoint Default Range
Temperature Setpoint 72
°
F 40 to 90
°
F (5 to 32
°
C)
Temperature Sensitivity 2.0
°
F 1 to 9.9
°
F (0.6 to 5.6
°
C)
Humidity Setpoint 50% 20 to 80% RH
Humidity Sensitivity 5% 1 to 30% RH
High Temperature Alarm 80
°
F 35 to 95
°
F (2 to 35
°
C)
Low Temperature Alarm 65
°
F 35 to 95
°
F (2 to 35
°
C)
High Humidity Alarm 60% 15 to 85% RH
Low Humidity Alarm 40% 15 to 85% RH