Heater cable having a tapered profile

A heater cable comprising:

• at least two bus wires;
• at least one positive temperature coefficient (PTC) core in contact with each of the at least two bus wires, the PTC core including at least one connecting portion extending between the at least two bus wires, the at least one connecting portion having a tapered cross-sectional profile wherein a first portion of the at least one connecting portion has a first thickness that is greater than a second thickness of the at least one connecting portion at one or more ends of the at least one connecting portion, each end approximate one of the at least two bus wires, wherein a ratio of the first thickness to the second thickness is greater that approximately 1.3.

A method of manufacturing a heater cable, the method comprising:

• forming a positive temperature coefficient (PTC) material into electrical contact with at least two bus wires to produce a heating element having a connecting portion of PTC material extending between a first bus wire and a second bus wire of the at least two bus wires;
• and
• forming a tapered cross-sectional profile in the connecting portion, wherein the tapered cross-sectional profile produces a first thickness in one or both of a first end and a second end of the connecting portion, and produces a second thickness in a thicker portion of the connecting portion between the first end and the second end, wherein the second thickness is greater than the first thickness, the second thickness and the first thickness being produced at a ratio greater than approximately 1.3.