How is a Class 2 circuit defined in relation to the power source?

A Class 2 circuit is defined as the wiring that originates from the load side of a Class 2 power source to connected equipment. This type of circuit is designed to limit the electrical output to ensure safety and reduce the risk of electrical shock or fire. In a Class 2 circuit, the source is typically designed to provide a maximum output of 100 watts or a current of 5 amperes. This limitation allows for a safe installation where the potential for overcurrent and excessive voltage is minimized, making it suitable for use in applications like fire alarm systems.

By focusing on the load side of the Class 2 power source, the wiring adheres to strict safety standards and is suitable for powering devices such as alarms, detectors, or notification appliances within a fire alarm system. This ensures that the connected equipment operates efficiently and safely without exceeding the limitations set by the circuit classification.