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Unformatted text preview: the sensing element reaches its alarm temperature. Eutectic salt does not allow current to flow at normal temp. In case of fire or over heat condition core resistance drops allows current flow between the signal wire and ground energized control unit (Magnetic amplifier) which in turn sounds the alarm. If any portion of sensing elements reaches alarm temp. KIDDE SYSTEM Two wires are imbedded in a special ceramic core with in an in conel tube. One of the wire is welded to die case at each end acts as on internal ground. The second wire is hot lead (above ground potential). That provides an electrical current signal when the ceramic core material changes resistance with changes in temp sensing. These elements are connected to relay unit. This unit constantly measures. The total resistance of the full sensing loops. Senses the average temperature as well as any hot spot. PRESSURE TYPE SENSOR RESPONDER TYPES It actuates when any portion of element reaches a temperature that would signal a fire condition or when a large portion of element is exposed to overheat condition (lower temp than fire) which could...
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This note was uploaded on 03/09/2011 for the course AIRCRAFT 2008.09.00 taught by Professor Dr.alan during the One '11 term at TAFE NSW - Sydney Institute.
- One '11