IEC 60034-7:2020 specifies the IM Code, a classification of types of construction, mounting arrangements and the terminal box position of rotating electrical machines. Two systems of classification are provided as follows:

- Code I: An alpha-numeric designation applicable to machines with end-shield bearing(s) and only one shaft extension

- Code II: An all-numeric designation applicable to a wider range of types of machines including types covered by Code I.

This third edition cancels and replaces the second edition, published in 1992, and its Amendment 1:2000. The main technical changes with regard to the previous edition are as follows:

- note on twin motors added

- reference to 4.3 instead of duplication of text

- new subclause on marking of shaft inclination or declination.