What is the term for the electrical devices used to signal alarms?

The term that is most commonly used to refer to the electrical devices designed to signal alarms is "Alert Systems." These systems are specifically engineered to detect dangerous or critical conditions and provide warnings through various means such as sirens, lights, or notifications. They encompass a range of devices that work together to ensure timely communication of alerts, making them vital in safety and security applications.

In contrast to other options, "Electronic Signal Units" may describe parts of a system but do not fully encapsulate the function of signaling alarms. "Indicators" typically point to specific readings or statuses rather than the comprehensive alerting mechanism. "Monitor Panels" often refer to interfaces displaying information rather than the devices responsible for generating alarms. Hence, "Alert Systems" effectively captures the essence and purpose of devices used to signal emergencies or alerts.