This clause of IEC 60398:2015 is replaced by the following. This International Standard specifies the test procedures, conditions and methods for determining the main performance parameters and operational characteristics of induction through-heating installations. Measurements and tests that are solely used for the verification of safety requirements of the installations are outside the scope of this standard and are covered by IEC 60519-1 and IEC 60519-3. This standard is applicable to the induction heating installations which through-heat the whole or part of metal billet or workpiece for its later hot forming (e.g. forging, extruding and rolling etc.), using low, mains or medium frequencies. It is possible to use it as a reference for other induction heating installations for heat-treatment and other purposes as well as superconducting d.c. induction through-heating installations. This standard includes the concept and material on energy efficiency dealing with the electrical and processing parts of the installations, as well as the overall performance.