在发生火灾时,有一种能感知火灾温度的电线称为线型火灾探测器,在日本称它为火灾枪知线(本文使用“检知线”这个名称)。这种检知线,是由两根有弹性的钢线组成,在钢线上被覆一层对热有敏感特性的特殊热塑性材料作为它的绝缘层,在两根线的外层还有护套,因此亦正常情况下两根钢线是相互绝缘的。 In the event of a fire, there is a wire that senses the temperature of the fire called a line fire detector, which in Japan calls it a firearm (this article uses the name “check wire”). The wire is made up of two flexible steel wires coated with a layer of special thermoplastic material that is sensitive to heat as its insulation and a sheath on the outer layers of the two wires , So also under normal circumstances the two wires are insulated from each other.