Rate-Anticipation Heat

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.


  • 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.
  • U L Listed
  • FM Approved