IEC 60255-26:2008

IEC 60255-26
Edition 2.0 2008-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measuring relays and protection equipment –
Part 26: Electromagnetic compatibility requirements

Relais de mesure et dispositifs de protection –
Partie 26: Exigences de compatibilité électromagnétique

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IEC 60255-26
Edition 2.0 2008-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measuring relays and protection equipment –
Part 26: Electromagnetic compatibility requirements

Relais de mesure et dispositifs de protection –
Partie 26: Exigences de compatibilité électromagnétique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
N
CODE PRIX
ICS 29.120.70; 33.100.10; 33.100.20 ISBN 2-8318-9853-6
– 2 – 60255-26 © IEC:2008
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope and object.6
1.1 Emission .6
1.2 Immunity .6
2 Normative references .7
3 Terms and definitions .8
4 Test requirements and procedures .9
4.1 Emission tests.9
4.2 Immunity tests.9
5 Criteria for acceptance .9
5.1 Emission tests.9
5.2 Immunity tests.9
6 Test report.9

Figure 1 – Ports for measuring relays and protection equipment .9

Table 1 – Emission tests – Enclosure port .9
Table 2 – Emission tests – Auxiliary power supply port .10
Table 3 – Immunity tests – Enclosure port .10
Table 4 – Immunity tests – Auxiliary power supply port .11
Table 5 – Immunity tests – Communication port.12
Table 6 – Immunity tests – Input and output ports.13
Table 7 – Immunity tests – Functional earth port.14

60255-26 © IEC:2008 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEASURING RELAYS AND PROTECTION EQUIPMENT –

Part 26: Electromagnetic compatibility requirements

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60255-26 has been prepared by IEC technical committee 95:
Measuring relays and protection equipment.
This second edition cancels and replaces the first edition published in 2004. This edition
constitutes a technical revision.
The main difference with respect to the previous edition concerns the reference to IEC 61000-
4 series and to CISPR 22.
The text of this standard is based on the following documents:
FDIS Report on voting
95/230/FDIS 95/234/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – 60255-26 © IEC:2008
A list of all parts of IEC 60255 series under the general title Measuring relays and protection
equipment, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
60255-26 © IEC:2008 – 5 –
INTRODUCTION
This part of IEC 60255 specifies all of the requirements for electromagnetic compatibility in a
single document. As such, it is considered as an overview document for measuring relays and
protection equipment. The detailed test procedures are given in other referenced standards.

– 6 – 60255-26 © IEC:2008
MEASURING RELAYS AND PROTECTION EQUIPMENT –

Part 26: Electromagnetic compatibility requirements

1 Scope and object
This part of IEC 60255 is applicable to measuring relays and protection equipment for power
system protection, including the control, monitoring and process interface equipment used
with those systems.
This standard specifies the essential requirements for electromagnetic compatibility for
measuring relays and protection equipment intended to be used at industrial locations.
Measuring relays and protection equipment used in substations and power plants may require
higher immunity test levels.
For equipment not incorporating electronic circuits, for example electromechanical relays,
tests according to this standard are not required.
The requirements specified in this standard are applicable to measuring relays and protection
equipment in a new condition and all tests specified are type tests only.
1.1 Emission
The object of this standard is to specify limits and test methods, for measuring relays and
protection equipment in relation to electromagnetic emissions which may cause interference
in other equipment.
These emission limits represent electromagnetic compatibility essential requirements and
have been selected to ensure that the disturbances generated by measuring relays and
protection equipment, operated normally in substations and power plants, do not exceed a
level which could prevent other equipment from operating as intended.
Test requirements are specified for the enclosure and power su
...