Book Contents

Options on the Display tab of the Trend Object Properties dialog box

The following table shows the options on the Display tab of the Trend Object Properties dialog box.

Options

Descriptions

Time format

Specify in what time format the trend shows. This setting affects every time display in the trend object.

The available options are:

  • 12-hour (AM/PM)
  • 24-hour
  • Use system time setting

    If system time format is selected, the format specified in the Windows Control Panel's Regional Options is used.

Chart radix

Specify the number base used to show numeric values on the chart. The available options are:

  • Decimal
  • Hexadecimal
  • Octal

    This setting affects the numbers on the y-axis and the x-axis if XY plot is selected. If the number of decimal places on the Y-Axis tab is set to anything other than 0, it overrides the radix selection and shows numbers as decimals.

Data point connection

Specifies whether data points on the chart are connected with a line or not connected.

The available options are:

  • Connect points. Shows data points connected with a line.
  • Show disconnects. Plot lines are disconnected between the start and end of a discontinuity in data. A discontinuity in data indicates a communication error or a break in a model’s data logging.
  • Show only markers. A marker is shown for each data point. Lines do not connect the data points, so the chart shows only those pens with assigned markers. Any pen without an assigned marker does not show on the chart.

Display milliseconds

If you select the standard chart style in the General tab, select this check box to include milliseconds in the time stamps shown on the x-axis legend at the bottom of the chart.

Display pen icons

Specifies whether pen icons show on the right side of the chart.

Pen icons indicate the last read value of each pen. Pen icons move to show the current value, even if the chart is not scrolling, so some pen icons might not appear to be at the end of a line.

Background color

This box shows the background color for the chart. Click it to select another color.

Use gradient style

Select this check box to show the background in a gradient color.

When this check box is selected, clicking the color square brings up the Gradient Fill dialog box.

Text color

Specifies the color of the text for the labels above and below the chart.

The labels on the vertical axis use the color of the first pen, unless you select Each pen on independent scale on the Y-Axis tab. In that case, the label's color matches the pen whose range is currently shown on the vertical axis.

If you select Isolated graphing on the Y-Axis tab, each pen is shown in a separate section of the chart with its own color labels.

Font

Click this button to open the Font dialog box and specify the type style used on the runtime chart display.

Allow scrolling

Select this check box to continually update the trend chart with new data at runtime. If this check box is selected, the Start Date and Start Time properties are not available. The available Scroll mode options are:

  • Continuous scroll. The trend chart scrolls from the right to the left for each new data reading.
  • Half Screen scroll. The trend chart scrolls half a screen at a time. Pens scroll from the middle of the chart to the right. When the pens reach the right side of the screen, the screen scrolls left and the pens continue from the middle of the chart.
  • Full Screen scroll. The trend chart scrolls a full screen at a time. Pens scroll from the left to the right, starting at the left-most side of the screen. When the pens reach the right side of the screen, the entire screen scrolls and the pens scroll again, beginning at the left side.

    If this check box is clear, the trend chart fills with new data up to the limit specified in its buffer size. Beyond that point, the trend chart does not update with new data until the operator manually toggles the scroll mode using the Pause Pen button.

Buffer for extra data

Specify the number of data points to be stored outside of the chart display area. The operator can view these data points by manual scrolling. The buffer size is limited to 32,767 data points. When the buffer is full, old data drops off.

To set the buffer size, specify the number of extra points to retain for each pen. For example, if a trend chart has 10 pens and the records per pen is set to 20, the trend chart stores 200 extra data points - 20 sets of data points for each of the 10 pens -outside of the display area. The more data points held in the buffer, the faster the trend can be strolled. However, larger buffer sizes also require more system resources. If you notice runtime trend performance slowing down, consider reducing the number of data points held in the buffer.

See also

Set up how the trend looks

Options on the Pens tab of the Trend Object Properties dialog box

Options on the X-Axis tab of the Trend Object Properties dialog box