Yokogawa YVP20S - Manual (Page 117)

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<Toc> <Ind> <12. TRENDING SERVICE>
IM 21B04C50-01E
The Trend Window is opened by right clicking on a device in the Device Tree, or by selecting
View>Trend in the IVI or PID dialogs. The trend window can display selected historical data
for up to 12 hours. The selected parameters may be actual valve position, target valve
position, PID process variable, and PID process setpoint. Click the Start menu button to
start trending and click Stop to stop trend. While the trend is stopped the time axis contin-
ues to increase. When trend is restarted, the time that it had been stopped will appear as a
blank. The vertical axis of the graph area can be zoomed by dragging a rectangle around
the area of the interest. A right mouse click returns the display to full scale.
Use the View menu to customize the trend.
Select which parameters are to be trended with Trend Selection. Set the duration of the
trend (up to 12 hours), and the time scale (45, 90, or 180 seconds) in scope settings
(Figure12.4).
Figure 12.3 Trend selection from View Menu