4 Wire Conventional Heat Detector General Fire Alarm System Compatiable Double Alarm Modes -- ROR, Fixed Temperature HEIMAN Fire Alarm Products4 Wire ... ~ +50 °C , Humidity ≤ 95%RHTemp. Trip Point57°C (135°F) Rate-Of-Rise8°C (15°F)/MinDetecting Range50m² at 6-12m ... on material, testing, quality, leadtime etc. Fire Alarm Heat Detector (Rate-Of-Rise, Fixed Temperature)