Siemens OP921 (S54320-FA-A2) Photoelectric Smoke Detector
Model OP921 incorporates an optical sensor using a light-scattering detection principle. The device utilizes advanced software algorithms to analyze the signals providing highly stable and accurate smoke detection.
Model OP921 is UL 268 7th edition listed incorporating advanced built-in ISOtechnologyTM - True Class-X SLC operation (use is optional), greatly improving system reliability and circuit integrity while providing advanced addressable fault finding.
Each detector fits into one (1) wall-or-ceiling footprint and only occupies one (1) address on the signal-line circuit (SLC). Model OP921 is a plug-in, two-wire, addressable photoelectric smoke detector whose value is increased with a built-in technology feature.
Model OP921 is Underwriters’ Laboratories Listed [UL268A Listed for direct in-air duct usage]. Each detector utilizes a dust-resistant photoelectric smoke chamber and
microprocessor-based electronics with a low-profile plastic housing. Every Model
OP921 fire detector is shipped with a protective dust cover.