Line-type heat detector based on thermoelectric couple principle

Abstract

A line-type heat sensing fire detector based on thermoelectric couple principle comprises a line-type temperature sensor element, a converter box and a terminal capacitor; wherein the line-type temperature sensor element comprises two detecting conductors and an NTC property barrier layer parallelly arranged between the two detecting conductors and at least one of the two detecting conductors is a thermoelectric coupling wire; and the resistance value Rz of the terminal resistance is larger than the critical resistance value R1j. The line-type heat sensing fire detector with terminal capacitor provided by the invention can ensure the detector alarms normally and reliably by using the method of leading the resistance value of the terminal resistance to be larger than the critical resistance value, and a resistance measurement unit which can monitor the line-type temperature sensor element alternatively with a voltage monitor unit, thus resolving the detect caused by alarming the accidents according to the voltage measurement value alone.

Description

technical field [0001] The invention belongs to the field of fire protection, in particular to a thermocouple-based linear temperature-sensing fire detector. Background technique [0002] The traditional thermocouple principle The linear temperature-sensitive fire detector is one of the commonly used linear temperature-sensitive fire detectors in the field of fire protection. figure 1 It is a structural schematic diagram of a traditional thermocouple-based linear temperature-sensing fire detector. like figure 1 As shown, this type of thermocouple wire-type temperature-sensing fire detector mainly includes a wire-type temperature sensing element 1 and one end connected to the wire-type temperature sensing element 1, and a voltage monitoring unit 7 is arranged inside, so that the voltage value of the entire circuit can be detected in real time , can carry out data processing at the same time, and output the conversion box 2 of alarm signal when the alarm parameter of the who...

AI Technical Summary

Problems solved by technology

However, this traditional thermocouple principle linear temperature-sensitive fire detector has the following problems: the described conversion box 2 cannot monitor the open circuit or open circuit fault of the linear temperature-sensitive fire detector

The method of adding terminal resistor 6 at the end of the above-mentioned online temperature sensing element 1 will make the voltage measurement values ​​Ua and Ub both smaller, and make the difference between Ua-Ub smaller. If the resistance value R of the terminal resistor 6 is selected too much Small, once the measured voltage Ua-Ub<0 occurs, the detector cannot meet the technical conditions stipulated in the national standard, which will cause the detector to fail to work normally, that is, the problem of unreliable alarm will occur

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