Alarm priority levels in SCADA systems - Step-by-Step Execution

Process Flow - Alarm priority levels

Alarm Triggered

↓

Check Alarm Severity

↓

Assign Priority Level

↓

Notify Operators

↓

Log Alarm Event

↓

Wait for Acknowledgement

↓

Resolve or Escalate

↓

End

When an alarm triggers, the system checks its severity, assigns a priority level, notifies operators, logs the event, waits for acknowledgement, then resolves or escalates the alarm.

Execution Sample

SCADA systems

alarm = "High Temperature"
severity = "High"
priority = ""
if severity == "Critical":
    priority = "Urgent"
elif severity == "High":
    priority = "High"
else:
    priority = "Normal"

This code assigns a priority level based on the alarm severity.

Process Table

Step	Condition Checked	Condition Result	Priority Assigned	Action Taken
1	severity == "Critical"	False		Check next condition
2	severity == "High"	True	High	Assign priority 'High'
3	else	Skipped	High	End priority assignment

💡 Priority assigned as 'High' because severity is 'High', no further checks needed.

Status Tracker

Variable	Start	After Step 1	After Step 2	Final
alarm	"High Temperature"	"High Temperature"	"High Temperature"	"High Temperature"
severity	"High"	"High"	"High"	"High"
priority	""	""	"High"	"High"

Key Moments - 2 Insights

Why does the code skip assigning 'Urgent' priority even though 'Critical' is checked first?

Because the severity is 'High', the first condition (severity == 'Critical') is false, so the code moves to the next condition and assigns 'High' priority as shown in execution_table step 1 and 2.

What happens if the severity is neither 'Critical' nor 'High'?

The else block assigns 'Normal' priority, ensuring every alarm has a priority level, as implied by the else condition in execution_table step 3.

Visual Quiz - 3 Questions

Look at the execution table, what is the priority assigned at step 2?

A Urgent

B High

C Normal

D None

💡 Hint

Refer to the 'Priority Assigned' column in execution_table row for step 2.

At which step does the code decide to stop checking conditions?

A Step 2

B Step 3

C Step 1

D After Step 3

💡 Hint

Look at the 'Action Taken' column in execution_table to see when priority is assigned and no further checks occur.

If severity was 'Critical', what would be the priority assigned at step 1?

A High

B Normal

C Urgent

D None

💡 Hint

Check the condition and priority assignment for 'Critical' severity in the code sample.

Concept Snapshot

Alarm priority levels assign importance to alarms based on severity.
Common levels: Critical -> Urgent, High -> High, others -> Normal.
System checks severity, assigns priority, then notifies operators.
Ensures quick response to serious alarms.
Always include a default priority for unknown severities.

Full Transcript

When an alarm triggers in a SCADA system, the system checks the alarm's severity level. Based on this severity, it assigns a priority level such as Urgent for Critical alarms, High for High severity alarms, or Normal for others. This priority guides how operators respond. The example code shows checking conditions in order and assigning the correct priority. The execution table traces these checks step-by-step, showing how the priority is assigned and when the process stops. Variables like alarm, severity, and priority change as the code runs. Key moments clarify why some conditions are skipped and how default priorities work. The quiz tests understanding of priority assignment steps and outcomes. This helps operators focus on the most important alarms first.