The Thermotech 302 Series rate-anticipation heat detectors operate within a controlled range of two to three degrees of their set points, regardless of the speed or rate of temperature rise. These detectors are available in either 135�F (57.2�C) or 194�F (90�C) ratings. The 302 Series are normally-open devices designed especially for fire detection and alarm systems. Features � Immediate response. The 302 Series activate whenever ambient air temperature reaches a detector�s setting, eliminating the thermal time lag inherent in conventional heat detectors. � Eliminates false alarms. The 302 Series do not respond to momentary temperature fluctuations below the selected temperature. � Universal application. The 302 Series can be used in all areas for any type of occupancy. � Self-restoring. � Hermetically sealed, shock resistant, corrosion resistant, and tamper-proof.