ABB SM3000 User Manual page 15

...2.3 Chart Views
Chart Annotation
 Alarms
 Operator Messages
Chart Duration
9 minute chart
30 minute chart
 1 hour chart
2 hour chart
3 hour chart
4 hour chart
6 hour chart
8 hour chart
12 hour chart
15 hour chart
16 hour chart
24 hour chart
2 day chart
4 day chart
7 day chart
32 day chart
If an alarm or operator message is obscuring part of a chart trace, use the Chart
Annotation option to hide or display alarms and messages on the screen.
Select the annotation required.  indicates the annotations selected.
The possible combinations are:
– No annotation (Alarms and Operator Messages both disabled)
– Alarm annotation only
– Alarms and Operator Message annotation
Operator Message annotation cannot be enabled unless Alarm annotation is also enabled.
Notes.
• If more than 40 icons are present on the screen, chart annotation is disabled
automatically.
• When chart annotation is disabled, new operator messages and alarms are still added
to the Alarm Event log – see Section 2.9.
Note. Applicable only to Circular Chart view in Historical Review mode and is greyed-out
in the menu until 'Historical review' is selected.
Use 'Chart Duration' to change the amount of data displayed on the screen in historical
review mode. A longer chart duration displays more data, a shorter chart duration displays
data over a shorter time period, but in more detail. In both cases, the full trace is preserved
by plotting the maximum and minimum samples for each display point.
Unavailable chart durations are greyed-out.
The chart durations available in the menu are determined by the faster of the primary and
secondary sample rates set for the process group during configuration – see Section
4.5.1. Unavailable chart durations are greyed-out.
Table 2.1 on page 14 shows the relationship between sample rate and chart duration for
the Circular Chart view.
Notes.
• A 'Please Wait' message appears in the status bar while the instrument retrieves data
from storage.
• Selecting a different chart duration does not affect the rate at which data is sampled.
• Changing the chart duration causes the time at the cursor position to change.
• If the chart duration is changed when in historical review mode, it reverts to that set
during configuration (see Section 4.5.1) upon exiting historical review mode.
2 OPERATION...
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