摘要 |
A continuous temperature sensing cable formed of a polymer containing conductive and semi-conductive fillers such as polyethylene with carbon black, powdered metals and metal oxides. The composition is extruded over a pair of elongated substantially parallel conductors which are spaced apart along the longitudinal length of the cable. The conductors are single-endedly connected to a control/alarm device for monitoring the continuous length of the temperature sensing cable. A critical voltage is applied single-endedly to the conductors and serially connected to an audible alarm to detect tunneling conduction when operated at a temperature near the melt temperature of the composition whereat the composition exhibits a negative temperature coefficient (NTC).
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