Liebert 50 & 60Hz - Manual (Page 45)

Microprocessor Control
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3.7 Time
The controller time clock must be set to allow for the setback control. The clock uses the 24-hour sys-
tem (i.e., 12 midnight is entered 24:00). To change the time press ENTER to select the function, then
use the UP/DOWN arrow to change the first character, press ENTER to store, then press the UP/
DOWN arrow key to change the character, press ENTER to store, etc. The real time clock is backed-
up.
3.8 Date
The controller date must be set to allow for setback control. To change the date press ENTER, then
use the UP/DOWN arrow to change the first character, press ENTER to store, press the UP/DOWN
arrow key to change the second character, etc.
3.9 Setback
The microprocessor can be programmed for night and weekend setback. Two (2) events can be pro-
grammed for a five-day workweek and two (2) events can be programmed for a two-day weekend. The
following table can be used to devise a setback plan.
3.10 Setup Operation
Selecting SETUP OPERATION from the Main Menu will display the following selections:
• RESTART TIME DELAY
• C/F DEGREES
• HUMIDITY CONTROL METHOD
• LEAD COMPRESSOR
• SHOW DIP SWITCH
• VALVE TIME (if valve present)
• CW FLUSH (if valve present)
Use the UP/DOWN ARROW to scroll through the submenu. Press ENTER to select a particular
function.
3.10.1 Restart Time Delay
This function delays unit restart after main power is restored to the unit. If several systems are oper-
ating, the time delays should be set to different values to cause a sequential start. Delay can be set
from 0.1 minutes (6 seconds to 9.9 minutes. Setting the value to zero (0) will prevent unit restart
when power is restored. In this case, the unit must be restarted manually by pressing the ON/OFF
button on the keypad.
Table 11 Night and weekend setback plan
Event Weekend Weekday
Time 1
Temperature1
Sensitivity 1
Humidity 1
Humidity Sensitivity 1
Time 2
Temperature 2
Sensitivity 2
Humidity 2
Humidity Sensitivity 2