Emerson Rosemount 3051S Series Reference Manual page 93

Reference Manual
00809-0200-4801, Rev DA
Figure 6-13. Adding History Recorder from DeltaV Control Studio
Follow through the Add History Collection dialog
Historian with the desired sampling period, compression, etc. By default the sampling period is 60
seconds, as shown in
want to look at changes in the standard deviation much faster than this. In that case, you will want to set
the sampling period to something smaller.
When adding a standard deviation for history collection in DeltaV, it is recommended that you not use
the default data compression settings. By default, the DeltaV Historian will log a new data point only
when the process value deviates by 0.01 or more. There are many diagnostics applications where it is
useful to look at changes in the standard deviation that are smaller than this. Therefore, it is
recommended that when logging the standard deviation, either the Data Compression should be
disabled (by unchecking the appropriate box) or the Deviation (EU) should be set to a much lower value,
for example, 0.001 or 0.0001.
Figure 6-14. DeltaV Add History Collection
Refer to the DeltaV books online for more details on the DeltaV Continuous Historian.
After the SPM value has been saved to the historian, when the DeltaV Process History View is opened for
the selected parameter, the graph will be populated with the historical data currently in the database
(Figure
Advanced Pressure Diagnostics
Figure 6-14. However, there are many diagnostics applications where one may
General configuration
6-15).
Advanced Pressure Diagnostics
(Figure 6-14), to add the parameter to the DeltaV
Advanced configuration
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