IEC 60747-5-6:2021 is available as IEC 60747-5-6:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC 60747-5-6:2021 specifies the terminology, the essential ratings and characteristics, the measuring methods and the quality evaluations of light emitting diodes (LEDs) for general industrial applications such as signals, controllers, sensors, etc.

LEDs for lighting applications are out of the scope of this part of IEC 60747.

LEDs are classified as follows:

- LED package;

- LED flat illuminator;

- LED numeric display and alpha-numeric display;

- LED dot-matrix display;

- infrared-emitting diode (IR LED);

- ultraviolet-emitting diode (UV LED).

LEDs with a heat spreader or having a terminal geometry that performs the function of a heat spreader are within the scope of this part of IEC 60747.

An integration of LEDs and controlgears, integrated LED modules, semi-integrated LED modules, integrated LED lamps or semi-integrated LED lamps, are out of the scope of this part of IEC 60747. This edition includes the following significant technical changes with respect to the previous edition:

- ultraviolet-emitting diodes (UV LED) and their related technical contents were added;

- power efficiency (ηPE) as part of electrical and optical characteristics were added;

- new measuring methods related to thermal resistance were added;

- hydrogen sulphide corrosion test was added to quality evaluation;

- some standards were added to the bibliography.