Final answer:
Fire alarm systems typically consist of detection, alarming, and monitoring components, with smoke detectors playing a key role in the detection of smoke through a circuit interrupted by smoke particles which then triggers the alarm.
Step-by-step explanation:
The three basic parts of any fire alarm system are the detection, alarming, and monitoring components. A typical smoke detector, which is a form of detection device, contains an electric circuit with two metal plates placed approximately 1 cm apart. A battery creates a voltage between the plates, and a small disk of Americium next to the plates ionizes the air, allowing a tiny current to flow between them.
This setup is responsible for the detection of smoke, as smoke particles disrupt the ionized air, causing the current to drop, which then triggers the alarm to go off. Furthermore, a three-wire system that includes a live/hot, neutral, and ground wire is often used in maintaining the safety of electric circuits within fire alarm systems, guarding against thermal and shock hazards and is complemented by safety devices such as Circuit breakers, Ground Fault Circuit Interrupters (GFCI), and isolation transformers to further enhance user safety.