What is an 'alarm and event' in a SCADA system?

• A. A notification indicating deviations or faults requiring operator attention.
• B. A routine data log entry.
• C. A system boot message.
• D. A status summary of equipment.

Answer: (A)

An alarm in a SCADA system is a real-time notification that a process variable has deviated from its limits or a piece of equipment has faulted, signaling the operator to take action. When an alarm occurs, it appears on the operator interface and is typically prioritized, while also being logged as an event to document what happened and when. This combo—the alert plus a record of the incident—is essential for timely response and later analysis. The other descriptions describe routine logs, startup messages, or general status views, none of which convey an actionable deviation or fault requiring operator intervention.