Performance Indices - ABB 800xA Operation

Performance indices

The weighted signals are summed that represents a health value for the loop
performance. This value is compared to predefined alarm thresholds to decide if an
alarm is necessary.
Performance indices
The performance indices used in CLAM are described in the list below. The result
from the index calculations can be reached in the following way:
1.
2.
Click on the tab Logic Block Parameters to see the results of the Index
calculations, pre-conditions.
Sl.No Name
1. Mean Loop Error
2. Standard Deviation
Loop Error
(Normalized)
3. Standard Deviation
Loop Error
(Engineering units)
4. Mean Process
Variable
96
Open Asset Reporter.
Right-click on the preferred row and choose Asset Monitor Status.
Table 9. Indices used in CLAM
Calculates the control error mean. Should be
close to zero if no permanent off-set is present.
Normalized to the interval [0-100 %].
Calculates the standard deviation of the
normalized control error. Presented as [0-100
%]. Should be as small as possible, usually [1-5
%].
Same calculations as index 2, but in absolute
engineering units. [min-max]. Should be small.
The mean process value documents the actual
operating point used during data collection (no
performance index). The mean value can be
used to analyze if certain control problems are
related to certain operation points. [min-max].
Section 8 Control Loop Asset Monitor (CLAM)
Description Index class
Basic statistics
Basic statistics
Basic statistics
Basic statistics
3BUA000150-600