Heating Group International heating cables are in fact heating elements. The execution is different, but the principal is the same as with any other heating element; heating cables have a certain resistance. When current groes through, this is transformed into heat by the friction. The resistance determines the heat transmission (in fact the electric power).
Especially with heating cables a control is crucial for a good operation. Depending on the application for the cable, Heating Group International is happy to advise you on the best control system.