IEC 60152:2021

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

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b) the concept of identifying conductors with hour number has been removed as the concept is considered out of date and other means for identifying conductors exists;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.

Désignation des déphasages par indices horaires des réseaux en courant alternatif triphasés

L'IEC 61052:2021 spécifie les méthodes et les règles en vue de la désignation du déphasage entre deux entités dans un réseau en courant alternatif triphasé. Les désignations sont destinées à figurer dans la documentation technique des installations, matériels et produits industriels, ainsi que sur les marquages des matériels et produits.
L'IEC 61052:2021 annule et remplace la 1re édition parue en 1963. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) le titre a été mis à jour en vue de refléter le contenu du nouveau document;
b) le concept d'identification des conducteurs par indices horaires a été supprimé, car il est considéré comme dépassé et qu’il existe d'autres moyens d'identification des conducteurs;
c) la définition de l’indice horaire (indice d’horloge) et celle du déphasage ont été ajoutées.

General Information

• Status: Published
• Publication Date: 08-Jul-2021
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: TC 3 - Documentation, graphical symbols and representations of technical information
• Drafting Committee: MT 23 - TC 3/MT 23
• Current Stage: PPUB - Publication issued
• Start Date: 23-Jul-2021
• Completion Date: 09-Jul-2021

Standards Content (Sample)

IEC 60152 ®
Edition 2.0 2021-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL PUBLICATION
PUBLICATION HORIZONTALE
Designation of phase differences by hour numbers in three-phase AC systems

Désignation des déphasages par indices horaires des réseaux en courant
alternatif triphasés
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IEC 60152 ®
Edition 2.0 2021-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL PUBLICATION
PUBLICATION HORIZONTALE
Designation of phase differences by hour numbers in three-phase AC systems

Désignation des déphasages par indices horaires des réseaux en courant

alternatif triphasés
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.020 ISBN 978-2-8322-9920-3

– 2 – IEC 60152:2021 © IEC 2021
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Hour numbers . 5
5 Phase difference . 6

Figure 1 – Illustration of hour number for three-phase transformer Dy11 . 6
Figure 2 – Examples of hour numbers representing phase differences . 7

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DESIGNATION OF PHASE DIFFERENCES BY
HOUR NUMBERS IN THREE-PHASE AC SYSTEMS

FOREWORD
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IEC 60152 has been prepared by IEC technical committee 3: Documentation, graphical symbols
and representations of technical information. It is an International Standard.
This second edition 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.

– 4 – IEC 60152:2021 © IEC 2021
The text of this International Standard is based on the following documents:
FDIS Report on voting
3/1490/FDIS 3/1516/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
DESIGNATION OF PHASE DIFFERENCES BY
HOUR NUMBERS IN THREE-PHASE AC SYSTEMS

1 Scope
This document 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.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
hour number
clock number
designation of a phase difference between the same quantity of two items in an AC system
3.2
phase difference
φ
for two sinusoidal quantities of the same frequency in a given order, difference between their
initial phases with possible addition of a multiple of 2π so that the difference is greater than −π
and not greater than π
 
Note 1 to entry: For the quantities at´( ) A´cos(ωϑt+ ´ ) and at˝( ) A˝˝cos(ωϑt+ ) the phase difference is
0 0
𝜑𝜑= 𝜗𝜗˝ − 𝜗𝜗´ + 2𝜋𝜋𝜋𝜋 where n is an integer, chosen so that −𝜋𝜋< 𝜑𝜑 ≤ 𝜋𝜋.
0 0
[SOURCE: IEC 60050-103:2009, 103-07-06]
4 Hour numbers
For the designation of a phase difference in a three-phase AC system, the following hour
numbers may be used:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11.
Each hour number shall represent the corresponding multiple of a phase difference of 30°.
= =
– 6 – IEC 60152:2021 © IEC 2021
EXAMPLE 1
A phase difference designated by the hour number 3 represents a difference in phase of 90°.
EXAMPLE 2
A phase difference designated by the hour number 5 represents a difference in phase of 150°.
5 Phase difference
For designation of a phase difference between two quantities, the hour number shall indicate
that the value of the second quantity is lagging the corresponding number of degrees compared
with the value of the first quantity.
EXAMPLE 1
To indicate the phase difference between the line conductors L1 and L2 in a three-phase transmission system, the
hour number 4 can be used to represent the phase difference of 120°.
For the designation of a phase difference between values of the same quantities with reference
to the i
...