What are the two types of electrical current used in fire alarm systems?

Fire alarm systems primarily utilize two types of electrical current: alternating current (AC) and direct current (DC). AC is characterized by the flow of electrical charge that periodically reverses direction, which is commonly found in standard electrical outlets and is often used for powering the main circuitry of fire alarm control panels. On the other hand, DC provides a constant flow of electric charge in one direction and is frequently used in devices like batteries that may back up the fire alarm system or in low-voltage signaling circuits.

This dual application of AC and DC currents allows for versatility in design and implementation of fire alarm systems. AC can support larger power requirements for components such as sirens and notification devices, while DC is often utilized for signaling and communication components, ensuring that the system functions effectively during alarms or emergencies. Understanding the role of both types of current is essential for professionals working with fire alarm systems, as it informs decisions related to installation, maintenance, and troubleshooting.