Analysis of Thin Film Fire Sensors. (1984)

• Record Type: Journal Article
• Authors: Zentai, G.; Illyefalvi-Vitéz, Zs.
• Is Part Of: Electrocomponent science and technology. Volume 11:Number 3(1984)
• Page Start: 209
• Page End: 214
• Publication Date: 1984
• Subjects: Electronics -- Periodicals; Electronic circuits -- Periodicals; 621.3815
• DOI: 10.1155/APEC.11.209
• Languages: English
• ISSNs: 0305-3091

Abstract

Abstract : The detection of fire in mines, industrial buildings, ships etc. is an important problem from both the economical and life-protecting aspects. The fire could be detected in several ways, e.g. by the measurement of flame-radiation, heat, pressure, temperature, the aerosols, the gases etc. The Department of Electronic Technology has developed a fire sensor which detects the rate of the increase of temperature. The fire sensor consists of two temperature sensitive resistors with different time-constants. If the increase of temperature in consequence of the fire is fast, the difference between the resistance of the temperature sensors is high, while a slow change in temperature causes only small differences. By connecting the temperature sensitive sensors into a bridge, the resistance difference can be easily detected. The temperature sensitive resistors are realized by thin film technology using platinum or nickel film on a thin glass or ceramic substrate. Because of the large surface and small volume of the resistor, its time-constant originally is very low but the time-constant could be easily increased by increasing the volume of the resistor. The present paper gives a detailed description of the analysis and the measurement of the temperature sensitive resistors with different time-constants. The technology of the films is also discussed.