Liebert AC4 User Manual

The hold delay timer also takes effect when the Liebert AC4 is powered up. All alarms are ignored until the
hold delay time expires.
• From the Setup Operation Menu, choose Hold Delay, as shown at right, and press Enter.
• To change the time delay in minutes and seconds (in the range of 00:00 to 99:59):
• For minutes (MIN), press and hold one of the arrow keys scroll through the numbers
00-99.
• Press Enter to advance to seconds (SEC).
• For seconds (SEC), press and hold one of the arrow keys scroll through the numbers
00-59.
• When finished, press Enter again.
7.8.5 Specify Restart Time
The restart delay timer directs the Liebert AC4 to wait a specified time
before changing the state of an output. This feature can prevent needless
responses to transient conditions.
If two or more outputs change state simultaneously, the Liebert AC4 begins
a new countdown between each output change of state.
The default is 6seconds (displayed as 00 MIN : 06 SEC).
• From the Setup Operation Menu, choose Restart, as shown at
right, and press Enter.
• To change the time delay in minutes and seconds (in the range
of 00:00 to 99:59):
• For minutes (MIN), press and hold one of the arrow keys
scroll through the numbers 00-99.
• Press Enter to advance to seconds (SEC).
• For seconds (SEC), press and hold one of the arrow keys scroll through the numbers
00-59.
• When finished, press Enter again.
7.9 Override Output
The Override Output feature allows you to manually change the state of any digital output to ON or OFF,
overriding automatic control by the Liebert AC4 (the default setting for all outputs). This menu also
allows you to release the manual override, returning any output to automatic control.
There are two ways to override automatic control of outputs:
• Use the Override Output menu, as described in this section, to turn any output ON or OFF.
• Use the hardware switch on the circuit board to force all four outputs ON at the same time
(see Controller Board Overview on page9).
After an output is forced manually ON or OFF, it remains in that state until returned to automatic control
through this menu.
Table 7.9 on the facing page summarizes the four types of control, including the abbreviated message
that appears on the LCD and in log reports.
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Liebert AC4 Specifications

General

Brand	Liebert
Model	AC4
Category	Control Unit
Language	English