Addressable Multi Detector ULCAPT340 Responds quickly to fast clean burning fires. Maintains the advantage of optical sensors when detecting smouldering fires. The thermal enhancement of Cooper ULCAPT340 sensor allows a higher alarm threshold, providing greater rejection of false alarms. The sensor will also give an alarm at temperatures above 135°F. For opto-heat and photoelectric operation the sensor automatically compensates for gradual increase in the scatter signal due to contamination e.g. dust build up.