Siemens OP121 Conventional Photoelectric Smoke Detector M500SF sensor type (such as photoelectric

sensor type (such as photoelectric or ionization) and an analog value

pull stations

Alternately

Supports compatible two-wire smoke detectors

417484 and 417485

Siemens OP121 Conventional Photoelectric Smoke Detector M500SF sensor type (such as photoelectricThe microprocessor controlled, self diagnostic circuitry contained in the Siemens photoelectric (conventional) smoke detector, Model OP121, eliminates an installers need of using burdensome sensitivity test equipment. The Model OP121 auto sensitivity feature originates from its internal, self monitoring circuitry, providing dynamic verification of sensitivity and or required maintenance. This detector type is commonly found on the following Siemens