Operational Alarm Definitions – Is Your SCADA System Setup to Respond to Critical Events?
Alarm Definitions are part of an Alarm Management System monitored in an operations or control center. Alarm Definitions play a critical role in creating a safe, reliable, efficient work environment. They are setup and incorporated as part of a well-designed Supervisory Control And Data Acquisition (SCADA) solution. For an alarm definition to be meaningful, it must be actionable and many factors must be first be considered during the planning and design.
This effort starts with answering the questions: what is your process and how will you measure, control, operate, and respond to normal and abnormal conditions?
- First, are the instruments used to control your system part of a SCADA solution?
- Are you able to monitor the data being produced by your instruments?
Managing Instruments Not Read by the SCADA System
An example of instrument that may be part of a process that is not being read by your SCADA system is a Level Gauge, such as an oil level gauge in a transformer. There are advantages and disadvantages to using instruments that are not being read by the SCADA system and it usually comes down to speed of implementation, ease of installation and of course, cost. For systems and processes where a Level Gauge is not sufficient and/or another part of the process requires the value as an input, the design would call for a Level Transmitter. The Level Transmitter would need to be sized, installed, and configured as part of the SCADA system.
Once you have a Level Transmitter that you deemed important to incorporate as part of your SCADA system, what happens when you have a high-level event? What happens when you have low levels of oil in your Transformer? This is where Alarm Definitions come back into play. The process owner will need to coordinate with the SCADA system provider and outline how important this Level Transmitter is and what abnormal conditions mean to the overall process.
Determining the Alarm Levels of Severity
The first and most important aspect of the Alarm Definition is Severity. How bad can the situation get if the alarm goes unattended? Well-designed Alarm Management Systems have different levels of Severity. There will be situations where you want to be aware of a situation but it may not be as time-sensitive as other alarms. The organization running the process would need to determine the different levels of Severity for their Alarm Management System. Common levels are: Critical, High, Low and Information. The different levels are usually segmented by time required to respond and impact. Impact can be measured in different degrees such as to impact to process, safety to others, environmental, schedule, cost and other factors. You would not want to make everything a Critical Alarm because you would lose the opportunity to determine the priority in what needs attention at each/every moment.
Contact Trimark to Learn More about Alarms and Utility-Scale SCADA Systems
Alarm Definitions have other considerations that were not presented in this article. Factors such as presentation, durations, shelving, acknowledgements, and others must be addressed. These items require the same level of pre-work and design to have an efficient and useful Alarm Management System. In the end, you can only act on what you measure, and if you measure it, you probably want to know it is running as designed. Trimark can help ensure that you are able to do that.
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