ACE Activity Analysis
The ACE Activity Analysis module developed its roots from the ISA 18.2 / IEC 62682 Clause 16 Monitoring and Assessment. The user interface of the Activity Analysis makes it easy to 1) select the analysis, 2) select a predefined analysis configuration, and 3) select the predefined query of records used in the analysis. And with all TiPSView user presentations, these selections can be saved as a View for easy access later or used for created automated reports. While many of these analyzes are based on alarm management principles, these analyzes are available with other scenarios such as operator workload studies, disabled alarm status metrics, and control loop statistics.
Frequency Analysis
A frequency analysis displays the number of times a field or group of fields occur. As a common example, a count of alarm records, grouped by the point name and associated alarm as specified in the analysis configuration, and sorted most to least frequent. This analysis can be used to evaluate alarm loads as specified under ISA 18.2 section 16.4.5.
Using the previous example, the Results tab is segmented by point name and alarm type depending on the duration analysis configuration. If an Alarm KB is linked to the real-time data, then the Tag Description and Alarm Priority are also displayed in the results as a default. This analysis has an associated drill-down tabs to show the Details of each record in the Results tab. The Details tab also has an associated drill-down tab to review the Source records before and after the Detailed record selected making data forensics an easy process.
Duration Analysis
A duration analysis shows how long events have been in alarm and also includes some problematic categories. There are 5 types of duration alarms:
- Time in alarm – how long an alarm has been in alarm (average time, maximum time, cumulative time)
- Time to acknowledge – how long the operator needed before acknowledging the alarm activation (average time, maximum time, cumulative time)
- Standing – alarm activation at the end of a time period (not return to normal)
- Stale – which alarms were in active alarm over a specific threshold, for example 24 hours
- Fleeting – an alarm that was active for a very short amount of time, for example 3 or 4 seconds, from the time the alarm became active to when it return to normal.
Duration analyses are used to discover alarms that are problematic under ISA 18.2 sections 16.5.6 and 16.5.7. According to ISA 18.2, there should be few stale alarms per operator console, with action plans to address them. No alarm should be intentionally designed to become stale and there is no long-term acceptable number of stale alarms.
The Results tab is segmented by tag and/or alarm type depending on the duration analysis configuration. If an Alarm KB is linked to the real-time data the Tag Description and Alarm Priority are also displayed in the results as a default. This analysis has an associated drill-down tabs to show the Details of each record in the Results tab. The Details tab also has an associated drill-down tab to review the Source records before and after the Detailed record selected making data forensics an easy process.
Chattering Analysis
A Chattering Analysis quickly informs about alarms that are activating and clearing several times in a specific time interval, for example having the same alarm go into alarm 3 times within 1 minute.
Chattering analyses are used to discover alarms that are problematic under ISA 18.2 section 16.5.6. According to ISA 18.2, chattering alarms are often high in the listing of the most frequent alarms. Chattering alarm behaviors should be eliminated via rationalization, and there is no long-term acceptable quantity of chattering or fleeting alarms.
The Results tab is segmented by point name and alarm type.
If an Alarm KB is linked to the real-time data the Tag Description and Alarm Priority are also displayed in the results as a default. This analysis has an associated drill-down tabs to show the Details of each record in the Results tab. The Details tab also has an associated drill-down tab to review the Source records before and after the Detailed record selected making data forensics an easy process.
The Count column is the number of Chattering Alarm occurrences that meet the analysis configuration. The Percent column indicates the percentage of chattering alarms relative to the total number of ALL alarms for the period, chattering or not.
Related Analysis
A related analysis displays alarms that frequently occur together. This exposes potentially duplicate alarms or alarms that are indicating similar conditions.
The Results tab is segmented by the point name and associated alarm state. If an Alarm KB is linked to the real-time data the Tag Description and Alarm Priority are also displayed in the results as a default.
The Count column is the number of Alarm occurrences for the Calendar period. The “Top Related Alarm” is the subsequent alarm that meets the analysis configuration for a specific Deadband and Percent Occurrence. The analysis provides information on alarms that occur together and help to illuminate a potentially causal relationship between them; for example, a tag point may be generating an alarm, not because there is anything wrong at that tag, but because another tag point upstream has an issue that is causing the alarm to activate. This information helps to narrow down the true source of a problem.
Flood Analysis
A flood analysis displays periods of time when alarms were occurring at a high rate. This can be an excellent measure of operator loading, particularly during process upsets, as well as identifying periods where the system is operating outside of industry best practice recommendations for alarm rate.
This analysis helps alignment with ISA 18.2 section 16.5.4. According to that section, alarm floods should be of short duration and low total alarm count, and an alarm system should be in flood for less than one percent of the time.
For each flood period a ‘Start Time’ shows the initial time the alarm rate was exceeded per the analysis configuration. The ‘End Time’ shows the time when the alarm rate fell below the threshold per the analysis configuration. The ‘Count’ column specifies the number of alarm activations during the flood period. The ‘Duration’ column provides the time duration between the Start Time and End Time.
This analysis has an associated drill-down tab to show the specific alarms in each flood time period.
Alarm State Analysis
An alarm state analysis provides statistics on the alarm, clear, and acknowledgment patterns for an alarm or group of alarms. Alarms are grouped by the fields specified in the analysis configuration and sorted most to least frequent. This analysis provides detailed insight into individual alarms and groups of alarms (grouped by area for example).
The ‘Alarms’ column shows the number of alarm activations for the total time range specified in the calendar. The ‘% of Total’ is the percentage of number of alarm activations for a specific tag divided by the total number of alarms during the period.
The ‘Clears’ column is the number of alarm clears (or Return to Normal) for the specific tag or alarm. The ‘Acks’ column is the number of alarm acknowledgments for the specific tag or alarm. The ‘% Ack’ column is the percent of acknowledged alarms over the total number of alarms for the specific tag.
Nuisance Analysis
A nuisance analysis provides a weighted frequency of alarms, grouped by tag, alarm type, and time. The data is rolled up at varying time intervals of Total, Months, Weeks, and Days depending on the length of the time range that the analysis is run for. This quickly highlights alarms that are consistently bothersome over time and also enables the user to quickly zero in on a particular time of activity with the multi-level summary intervals.
The results of the Nuisance Analysis are segmented by the Tag and Alarm Type. The ‘Start Time’ and ‘End Time’ show the initial time and last time the alarm was active during the time range specified. If an Alarm KB is linked to the real-time data, the Tag Description and Alarm Priority are also displayed in the results.
Additional filtering in the Analysis provides a granular approach to identify chronic alarm problems vs alarms that occurred during a process upset.
Overview Analysis
The Overview Analysis is a list of metrics from ISA 18.2 / IEC 62682 Clause 16 that provides a user with a general idea of the alarm system’s health.
