Smoke alarm with dual sensing technologies and dual power sources

摘要

A smoke alarm having both an ionization detector and a photoelectric detector coupled to each other to generate an alarm signal when either of the detectors senses a potential fire. The smoke detector includes a power supply circuit having both an AC power supply and a DC battery power supply. During normal operating conditions, the AC power supply operates both the ionization detector and the photoelectric detector of the smoke alarm. Upon power interruption, the DC battery supply provides power to operate both the ionization detector and the photoelectric detector. The smoke alarm includes an interconnect that allows multiple smoke alarms to be coupled together.