Which type of annunciator uses colored lamps or LEDs?

The type of annunciator that uses colored lamps or LEDs is the graphic annunciator. Graphic annunciators are designed to provide visual information about the status of a fire alarm system. They typically display a graphical representation of the facility layout along with colored indicators that signify different alarm conditions, such as red for fire, yellow for trouble, or green for normal operation. This visual cue allows operators and first responders to quickly assess the situation and identify the location of an alarm or issue.

In contrast, interactive, conventional, and addressable annunciators may use other methods to convey information, such as numerical displays or textual descriptions, but they do not primarily rely on a graphical system with colored lamps or LEDs to communicate urgent status, making the graphic annunciator the most definitive choice for this question.