Change the range of data displayed on a trend chart

Change the minimum data value, maximum data value, and time span of a trend chart to change the range of data displayed. By default, trend charts show data with values between 0 and 100. The default span of time of a trend chart is one second or 1000 milliseconds.
IMPORTANT:
A trend chart clears all traces and resumes when the MaxValue or MinValue property of a trend chart changes on the HMI device. For example, changing the MaxValue or MinValue property value of a trend chart through a Text Input graphic element causes the trend chart, even while paused, to resume at the current time. Historical data, if available in a data log, appears for data before the current time. The trend chart discards all other data and plots new data.
To change the range of data displayed on a trend chart
  1. Select the trend chart on the screen.
  2. In the
    Properties
    window, select the
    Properties
    tab.
  3. Expand the
    General
    category.
  4. In the
    MaxValue
    box, type any numeric value greater than the
    MinValue
    property value.
  5. In the
    MinValue
    box, type any numeric value less than the
    MaxValue
    property value.
    TIP:
    The value in the
    MinValue
    box must be less than the value in the
    MaxValue
    box.
  6. In the
    TimeSpan
     box, type the span in seconds. A valid time span is between 1 and 3600 seconds. 3600 seconds equals one hour.
  7. In the
    SampleRate
    box, type the rate, in milliseconds, at which the trend chart requests data from the controller. Valid sample rates are between 500 and 60000 milliseconds which equal one-half second and 60 seconds.
    TIP:
    Tips:
    • If the trend chart requests data more frequently than data updates in the controller, the data plotted may not appear in a linear fashion on the trend chart.
    • To avoid slow panning on a trend chart that has a time span over 30 minutes, enter a minimum of 1000 milliseconds, or 1 second, in the
      SampleRate
      box.
    • Trend charts automatically display data from a data log for the specified tag. Tags may exist in more than one data log. The trend chart uses the data log that contains a matching sample rate. If there is more than one data log with a matching sample rate or there is no data log with a matching sample rate, the trend chart uses the first data log.
    • Data displaying in real time on the HMI device uses the sample rate of the trend chart.
    • Data displaying historical values on the HMI device uses the sample rate of the data log for the project.
    • The range of signed integers that is represented without losing precision is –(2^53)..(2^53). All integer values outside this range are rounded to 15 significant digits. For example, 8765432109876543210 is rounded to 8765432109876540000, losing the precision for the last four least significant digits.
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