Snc-300 non-addressable photoelectric smoke/heat detectors are state-of-the-art detectors suitable for connection To 2-wire or 4-wire non-addressable fire detection control and indicating equipment, or to addressable fire detection Control and indicating equipment that can accept non-addressable type detectors. Advanced electronics in conjunction with a photoelectric smoke sensing chamber and an electronic thermistor Provide early detection of fire and high immunity against unwanted alarms. The heat sensor provides sensitive Rate-of-rise operation or fixed-temperature operation when the response threshold value is exceeded. Photoelectric smoke and heat sensors Analogue detection discrimination Dual leds for 360° visibility 2-wire and 4-wire models for dc 12 v and dc 24 v operation 4-wire model for dc 48 v operation 4-wire models available with a n/o alarm relay output 4-wire models available with auto-reset 2-wire models available with remote led output Connects to zone monitor for use with addressable control and indicating equipment