Final answer:
Alarm sensors are essential components of an alarm system, divided into three classes: magnetic contact sensors, infrared motion sensors, and glass-break sensors.
Step-by-step explanation:
An alarm system consists of various components, and one of the essential ones is alarm sensors. These sensors play a crucial role in detecting and alerting the system about potential threats or intrusions. Alarm sensors can be categorized into three primary classes:
- Magnetic Contact Sensors: These sensors use magnets to detect changes in magnetic fields when doors or windows are opened. They are commonly used to secure entry points.
- Infrared Motion Sensors: Also known as passive infrared (PIR) sensors, they detect changes in heat or movement in their surroundings. They are effective in detecting human presence and motion within a defined area.
- Glass Break Sensors: These sensors are designed to identify the sound frequency generated by breaking glass. They can be installed near windows to trigger an alarm if someone attempts to break in.