Emerson Rosemount 3051CF Series Reference Manual page 128

Advanced pressure diagnostics
July 2020
SPM_StDev
Current Standard Deviation of the process variable.
SPM_StDev_Change
Percent change between the Baseline Standard Deviation and the Current Standard
Deviation.
SPM_Timestamp
Timestamp of the last values and status for the SPM.
SPM_Status
Current state of the SPM Block; possible values for SPM status are as follows:
SPM_Status
Status value
Inactive
Learning
Verifying
Monitoring
Mean Change
Detected
High Variation
Detected
Low Dynamics
Detected
Not Licensed
In most cases, only one of the above SPM status bits will be active at one time. However, it
is possible for Mean Change Detected to be active at the same time as either High
Variation Detected or Low Dynamics Detected.
7.5.5 Alerts
When any of the SPM detections (Mean Change, High Variation, or Low Dynamics) is
active, SPM generates a Fieldbus NE107 or Plantweb
Change Detected (SPM)
SPM NE107 or Plantweb alert.
128
Description
User command in Idle, SPM not enabled, or the function block is not
scheduled.
Learning has been set in the user command, and the initial baseline
values are being calculated.
Current baseline values and previous baseline values are being compared
to verify the process is stable.
Monitoring the process and no detections are currently active.
Alert resulting from the mean change exceeding the threshold mean
limit. Can be caused by a set point change, a load change in the flow, or
an obstruction or the removal of an obstruction in the process.
Alert resulting from the Stdev change exceeding the threshold high
variation value. This is an indicator of increased dynamics in the process
and could be caused by increased liquid or gas in the flow, control or
rotational problems, or unstable pressure fluctuations.
Alert resulting from the Stdev change exceeding the threshold low
dynamics value. This is an indicator for a lower flow or other change
resulting in less turbulence in the flow.
SPM is not currently purchased in this device.
and sends it to the host system. Note that there is just one
Reference Manual
00809-0100-4774
®
alert in the device Variation
Rosemount 3051