Emerson Rosemount 3051CF Series Reference Manual page 121

Reference Manual
00809-0100-4774
Figure 7-2: Changes in Process Noise or Variability and Affect on Statistical
Parameters
A. Normal.
B. Increased noise.
C. Reduced noise.
D. Standard deviation increases or decreases with changing noise level.
E. Mean is unchanged.
The device can provide the statistical information in two ways. First, it can make the
statistical parameters available to the host system directly via F
communication protocol or FF to other protocol converters. Once available, the system
may make use of these statistical parameters to indicate or detect a change in process
conditions. In the simplest example, the statistical values may be stored in the DCS
historian. If a process upset or equipment problem occurs, these values can be examined
Reference Manual
Advanced pressure diagnostics
July 2020
™
Fieldbus
OUNDATION
121