IEC 60375:2018

IEC 60375 ®
Edition 3.0 2018-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Conventions concerning electric circuits

Conventions concernant les circuits électriques

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IEC 60375 ®
Edition 3.0 2018-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Conventions concerning electric circuits

Conventions concernant les circuits électriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.060; 01.080.40 ISBN 978-2-8322-5597-1

– 2 – IEC 60375:2018 © IEC 2018
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Orientation of geometrical objects . 15
4.1 Orientation of a curve . 15
4.2 Orientation of a surface. 15
4.3 Arrows perpendicular to the plane of the figure . 15
5 Conventions concerning currents . 15
5.1 Physical direction of current . 15
5.2 Reference direction of current . 16
5.3 Indication of the reference direction for currents . 16
5.3.1 Indication of the reference direction for currents for a branch . 16
5.3.2 Indication of the reference direction for mesh currents . 16
5.4 Kirchhoff law for nodes . 17
6 Conventions concerning voltages . 17
6.1 Physical polarity of voltage . 17
6.2 Reference polarity for a pair of nodes . 18
6.3 Indication of the reference polarity . 18
6.3.1 First method . 18
6.3.2 Second method. 18
6.3.3 Third method . 19
6.4 Kirchhoff law for meshes . 19
7 Conventions concerning power . 20
7.1 Physical direction of power . 20
7.2 Reference direction of power . 20
7.3 Indication of the reference direction of power . 20
7.4 Combined conventions . 20
7.4.1 General . 20
7.4.2 Motor convention . 21
7.4.3 Generator convention . 21
8 Conventions concerning two-port networks . 21
9 Conventions concerning sources . 22
9.1 Conventions concerning voltage sources . 22
9.1.1 Independent voltage sources . 22
9.1.2 Controlled voltage sources . 22
9.2 Conventions concerning current sources . 23
9.2.1 Independent current sources . 23
9.2.2 Controlled current sources . 23
10 Conventions concerning passive elements. 24
10.1 General conventions . 24
10.2 Resistive elements . 24
10.2.1 Resistive two-terminal elements . 24
10.2.2 Resistive n-terminal elements . 25
10.3 Capacitive elements . 26
10.3.1 Capacitive two-terminal elements . 26

10.3.2 Capacitive n-terminal elements . 27
10.4 Inductive elements . 29
10.4.1 Inductive two-terminal elements . 29
10.4.2 Inductive n-port elements . 30
11 Complex notation . 32
11.1 General . 32
11.2 Conventions concerning complex representation of sinusoidal quantities . 32
11.3 Reference direction of a complex current . 32
11.4 Reference polarity for a complex voltage . 33
11.5 Complex representation of Ohm's law . 34
11.6 Conventions concerning the graphical representation of phasors . 35
11.7 Conventions concerning phase differences . 35
11.8 Conventions concerning power . 36
11.8.1 Time-dependent electric power . 36
11.8.2 Complex power . 36
Bibliography . 37

Figure 1 – Orientation of a curve . 15
Figure 2 – Orientation of a surface . 15
Figure 3 – Indication of the reference direction for a current by an arrow . 16
Figure 4 – Indication of the reference direction using the node names . 16
Figure 5 – Indication of the reference direction for mesh currents . 17
Figure 6 – Examples of the Kirchhoff law for nodes . 17
Figure 7 – Indication of the reference polarity by means of plus and minus signs . 18
Figure 8 – Simplified indication of the reference polarity by means of plus signs . 18
Figure 9 – Indication of the reference polarity by an arrow .
...