Electric heat-tracing systems are based on the principle of converting electrical power into heat and transferring it to the pipe and the fluid it contains.

Almost all commercial electrical heat monitoring systems used today are of the resistor type. Heat transfer is provided through cables placed on the pipe.

When current is passed through resistive elements, heat is produced in proportion to the square of the current and the resistance of the element to the current.

In other special systems, impedance, induction, and skin-effect effects are used.

Taken from UCH Wiki. ===== NOTLAR =====