IOM 1281-2 • CENTRIFUGAL WATER CHILLERS 56 www.DaikinApplied.com
Operation
Figure 67: Trend History Screen
Trend History Screen
The Trend History Screen (
Figure 67
) is accessed by clicking
the TREND button at the bottom of any screen. The Trend
History Screen allows the user to view the various parameters
listed on the right side of the screen.
The Trend History Screen can display history for 24-
hour, 4-hour, 1-hour, or 15-minute periods by pressing the
appropriate button, respectively. For any time period, the trend
will display the current time beginning on the right of the screen
with history flowing to the left.
When the Unit Control Processor is powered on after being off,
the Trend History Screen will only display the history starting
from the time the Unit Control Processor was powered on.
Previous trend history can be downloaded but there will be a
gap in the data from when the Unit Control Processor was off.
Trend history is not affected if only the HMI screen (not the Unit
Control Processor) is off or in sleep mode. For details on how
to download the trend history, reference the
“Alarms”
section
Alarms
The Alarm information (
Figure 68 and Figure 69
) is accessed
by touching the ALARM icon at the bottom of the HMI and then
the Active or History tabs at the top of the screen. As noted on
page 37,
an active alarm will turn the icon flashing red.
There are three types of entries in the table:
1.
Critical Alarm (Red Text)
- This is an equipment
protection alarm that will shut a unit or compressor off if
not corrected.
2.
Warning (Yellow Text)
- This alarm limits compressor
loading in response to an out-of-normal condition or
may only be a notification to indicate that the condition
requires attention. This alarm may not cause a shutdown.
If the condition that caused a warning is corrected, the
alarm light will be cleared automatically.
3.
Informational (Black Text) - This notification type reports
actions the unit may be taking while trying avoid a
warning or critical alarm.
The Alarm Active and History Screens display a maximum of
18 alarms for the current date with the most current alarms
listed on top. Each alarm displays the date stamp, action taken,
and the cause of the alarm. See the Alarm tables starting
on
page 59
for specifics on alarms that may occur. Alarm
history data is held for 365 days as shown on the Interface tab
in
Figure 66
.