Heating cables are commonly referred to as heat trace cables, heat tracing, or heat tape, while the most advanced cable design, self-regulating heating cables, are also known as self-limiting cables. Whatever they are called, all work largely on the same principle: when voltage is applied across a length of wire of a given resistance, it then dissipates a fixed level of power in the form of radiating heat based on ohms law. Heat is emitted due to the resistance in the cable alloys as the current moves through it, thereby warming up the immediate physical surroundings.
For that reason, heating cables are used in a multitude of applications, from pipe freeze protection, to snow melting on a sidewalk or driveway, to preventing ice dams on roofs, to keeping dangerous icicles from forming in gutters and downspouts, to indoor floor warming when installed under tiles or hardwood floors. In addition, heating cables are used in a range of industrial freeze protection and process maintenance applications to keep liquids in pipes at a constant temperature to prevent degradation of the liquid or to maintain viscosity for flow conditions. Industrial heating cables will not be addressed in this article.