Emerson 20/20 Manuel D’Utilisation

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Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.8.5153
Section 15 • Trend Chart
Overview
This screen allows the operator to view and adjust set-
tings for the trend chart, see Figure 15-1. Trend Chart 
Screen. Trending feature can be started & stopped from 
this screen. Up to four variables can be selected for plot-
ting on screen. Each variable is assigned one of four 
colors; the plotted trace and the vertical axis labels for 
a variable will be in its assigned color. The operator can 
select from viewing the plot to selecting which variables 
and time intervals to show as often as necessary. The 
vertical axis scaling and offset for each variable plotted 
is based on its range of values over the entire data plot-
ted on screen. The data available for display is 120 hours 
maximum.
Chart Operation
Pen Selection:
•  Pen selection allows operator to select different pens 
for plotting of data on the screen. The operator can 
select “None” as an option for disabling plotting of 
data for particular pen. Options in pen selection 
drop-down box will depend on channels selected in 
Trend Setup screen.
Start/Stop:
•  This button allows the operator to start/stop trend 
feature. When trend feature is not running, button 
will display “Start” and will be green in color. While 
trend feature is running, button will display “Stop” 
and will be red in color. When “Stop” button is 
pressed, trend data is saved to a fi le.
Zoom In/Out:
•  These buttons allow the operator to adjust the num-
ber of data points plotted on the screen. At maximum 
Figure 15-1. Trend Chart Screen