Abstract: An apparatus for monitoring the current flow through a variable load such as various lengths of heater cables. The apparatus can detect a wide range of currents so that the size of the load can vary.

Abstract: An improved self-regulating pipe heating cable assembly that includes a self-regulating cable having a temperature-sensitive conducting layer between a pair of busses and a plug coupled to a first end of the self-regulating cable for supplying electricity thereto. The improved self-regulating pipe heating cable assembly includes an indicator coupled to the self-regulating cable at a location other than where the plug is connected. The indicator is responsive to the supply of electricity to the self-regulating cable so that proper operation of the self-regulating heating cable assembly can be determined.

Abstract: An improved thermostatic electrical cable heater is disclosed which permits more accurate temperature sensing by the thermostat and better control over the temperature of the object being heated. This improved sensing and temperature control is accomplished by isolating the thermostat and its surrounding insulated envelope from the electrical resistance heating elements of the cable heater.