These requirements cover electrically-actuated transmitters intended for permanent installation and use in ordinary indoor locations in accordance with the National Electrical Code, NFPA 70, and the National Fire Alarm Code, NFPA 72.

A transmitter covered by these requirements consists of a unit assembly of related electrical and mechanical parts in an enclosure. Installation wiring terminals are included for the connection of power supply circuits routed through the transmitter by a prescribed scheme of circuiting to terminals for the connection of conductors of circuits to separate transmitter actuated devices and to circuits of a system-control unit and other indicating devices.

An electrically-actuated transmitter having a pre-wound signaling mechanism and equipped with an integral part to permit manual actuation, and similar combination devices, will be evaluated with regard to compliance with the applicable requirements for both electrically-actuated transmitters and manually-actuated signaling boxes.