User guide

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addVANTAGE Pro 6.2 User Guide CHAPTER 4
The Trend Viewer
display, click the OK button. The Trend viewer displays the tags and their data in
a graphic form.
Figure 36. Selecting, Adding, and Removing Tags
Note: If no plots are displayed, check the date and use the arrows and the calendar in
the Trend viewer to move to a date and time where you have data.
You can also use the extensive features available in the Trend Options dialog to
customize the way your graph looks by viewing and changing the options on the
Y-axis, Plots, Thresholds, and Display tabs.
Y-axis Tab
Following is an explanation of the options on the Y-axis tab shown in Figure 36.
• Use sensor color as Axis color. The Y-Axis and sensor colors are assigned by
addVANTAGE Pro and are identical by default. If you leave this checkbox
unselected, you can use the color chooser you see to change the y-axis
color, but the corresponding color of the tag on the graph will not change. If
you select this checkbox, the color of the y-axis will be the same as the
sensor color (as displayed on the Plot tab).
• Scale
• High /Low: The scale refers to the tag’s value range—in other words,
the maximum or minimum value that is expected. If the tag can
deliver data only in the range of
-60°C to +40°C, for example, you need not enter +1000°C for the
High and -200°C for the Low because no one would see the trend
curve.
Normally, only people who know that their value is within a certain
range use the Scale fields. For example, say you have a special Temp
sensor in a production process. Its range is always between 20°C and
25°C but it is very important to see small changes. For this sensor, you
would choose settings of Low=20 and High=25.
•The Defaults button resets the High/Low settings to the tag’s default.
• If you select the Autoscale checkbox, the minimum and maximum values of
the sensor will be determined automatically within the current time range.
The Scale High and Low fields are ignored in this case.
• If you select the Always show y-axis checkbox, the y-axis for the current
sensor (meaning the sensor whose y-axis properties you are viewing) will
be shown on the grid always, even when another sensor is selected.
Normally, when you select a sensor in the Legend section, the y-Axis is