The ESL 429AT is a low-profile, self-diagnostic, two-wire smoke detector work on the light scattering principle. A pulse infrared light-emitting diode serves as the light source, and a high-speed photo-diode as the sensing element. This design has superior protection against false alarms caused by dust, insects, RF and ambient-light.
This type of smoke detector is especially suited for residential occupancies, including hotels, motels and dormitories, as well as other commercial and industrial fire-system applications.