Siemens OP921 Photoelectric Smoke Detector uses microcontroller circuitry and surface-mounted technology for maximum reliability. This Siemens Smoke Detector incorporates an optical sensor using a light-scattering detection principle. The device uses advanced software algorithms to analyze the signals that provide highly stable and accurate smoke detection. These detectors fit into one ceiling/wall footprint and only occupy (1) address on the signal line circuit.  This Smoke Detector is a plug-in, two-wire, addressable photoelectric smoke detector whose value is increased with the built-in ISOtechnology feature. This Photoelectric Smoke detector uses a dust-resistant photoelectric smoke chamber and microprocessor-based electronics with a low-profile plastic housing. Every OP921 smoke detector is shipped with a protective dust cover.
Applications: Home, Office, Malls, Hotel Lobby, Air Ducts, Indoor Stadiums, Hospitals, Clean rooms, etc.