... non-polar input,Automatic reset and power-off reset,Alarm temperature:57C(135F),Meets EN54-7,UL539 operating ... Glass Fiber circuit board. MCU processing adopted,eliminate false alarm. Relay output/LED indicator. SMT manufacture technology,high stability. ... reset. detection sensitivity:2.06%/ft operating temperature:-10 +50.Alarm temperature:57C(135F). operating humidity :≤95RH. Dimension: Φ100* ...