Electrical device termination high temperature indicator

摘要

Temperature indicating apparatus for sensing overheating at a pair of terminals on an electrical power line comprises a neon gas-filled glow tube and a thermistor electrically coupled in series across the terminals, with a resistor electrically coupled in parallel with the glow tube. The thermistor is thermally coupled to the terminations so that an excessive temperature rise at either terminal decreases the thermistor resistance to a level at which sufficient voltage appears across the glow tube to ignite the glow tube and provide a visual indication of overheating. The circuit readily lends itself to a plug-in type configuration if the terminals to be monitored are in a duplex receptacle, or to employment in a cube tap.