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Unformatted text preview: ical current flow in the test circuit. If current flow falls below t preset value alarm cct activate visual and audio alarms. SOLID STATE TYPE: It operates comparing signals from two detecting elements. One will be the area being monitored other exposed to outside air. Detecting elements consists of heating coil encased in a coating of semi conducting material. Carbon monoxide or nitrous oxide present will be absorbed by this coating and will change the current currying ability of detector. These sensors are connected in bridge circuit. When both elements conduct evenly. Bridge balances no warning signal is present. If the area being monitored has co unbalanced condition created across bridge and warning cct illuminates cockpit warning lamp and audio system. Visual Smoke Detectors: Installed in the flight engineers panel the inside of the chamber is painted non reflective back a glass observation windows a light shines across the chamber in such a way that it illuminate any smoke that is present. Air pulled from the compartments to be mon...
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- One '11