I would like to know whether Trends in PI Process Book display multiple Y axis (max of 6) and can I programmatically access this in a.net application
Yes in the trend definition, you can select single or multiple scales.
ProcessBook symbols are accessible via VBA. Specifically, you can do this via the Trend object. See the ProcessBook Programmer Reference Guide from the PB menu under Help.
To access Processbook symbols from .NET. I believe you can use the interops to do that. You will need the Processbook library in your .NET project. Specifically, look at the Trend class. I have it here for your convenience.
The MultipleScales property is a Boolean property that determines whether all the traces of the plot use the same vertical scale or not. It serves the same function as the Single Scale and Multiple Scales option buttons in the Trend Definition dialog.
object.MultipleScales = Boolean
.MultipleScales = Boolean
Return type is boolean.
If TRUE, a separate upper and lower limit for the Y axis for each trace in the trend is displayed. If FALSE, all traces are plotted against the same Y axis upper and lower limits.
If this property is set to TRUE, the current settings of Trend.ScaleMax and Trend.ScaleMin are used for all traces. If this property is set to FALSE, then each trace acquires the current setting of Trend.ScaleMax and Trend.ScaleMin as a starting value subject to subsequent changes.
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