IEC 60152:2021 

Designation of phase differences by hour numbers in three-phase AC systems


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IEC 60152:2021 specifies methods and rules for the designation of phase difference between two items in a three-phase AC system. The designations are intended to be applied in the technical documentation of industrial installations, equipment, and products, and also on markings of equipment and products.
IEC 60152:2021 cancels and replaces the first edition published in 1963. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the title has been updated to reflect the content of the document;
b) the concept of identifying conductors with hour number has been removed as the concept is considered out of date and other means for identifying conductors exists;
c) definition of hour number (clock number) and phase difference introduced.

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Additional information

Publication typeInternational Standard
Publication date2021-07-09
Available language(s)English/French
TC/SCTC 3 - Documentation, graphical symbols and representations of technical informationrss
ICS29.020 - Electrical engineering in general
Stability date  2030
File size1147 KB

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