prEN IEC 61936-0:2026

SLOVENSKI STANDARD
01-junij-2026
Električne inštalacije nad 1 kV AC in 1,5 kV DC - 0. del: Načela, ki jih je treba
upoštevati pri projektiranju in postavitvi visokonapetostnih inštalacij - Varnost
visokonapetostnih inštalacij
Power installations exceeding 1 kv AC and 1,5 kv DC - Part 0: Principles to be observed
in the design and erection of high voltage installations - Safety of high voltage
installations
Ta slovenski standard je istoveten z: prEN IEC 61936-0:2026
ICS:
29.020 Elektrotehnika na splošno Electrical engineering in
general
29.080.01 Električna izolacija na Electrical insulation in
splošno general
29.240.01 Omrežja za prenos in Power transmission and
distribucijo električne energije distribution networks in
na splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

99/529/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61936-0 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2026-04-10 2026-07-03
SUPERSEDES DOCUMENTS:
99/484/CD, 99/489A/CC
IEC TC 99 : INSULATION CO-ORDINATION AND SYSTEM ENGINEERING OF HIGH VOLTAGE ELECTRICAL POWER INSTALLATIONS ABOVE
1,0 KV AC AND 1,5 KV DC
SECRETARIAT: SECRETARY:
Australia Ms Erandi Chandrasekare
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):
TC 99 Horizontal Group Safety
TC 1,TC 2,TC 8,TC 9,TC 11,TC 14,TC 17,TC 18,TC
22,TC 42,TC 44,TC 64,TC 88,TC 115,TC 117,TC
122,PC 127,PC 128,TC 129
ASPECTS CONCERNED:
Safety
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for
Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
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they are aware and to provide supporting documentation.
Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some Countries”
clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is the final stage for
submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Power installations exceeding 1 kV AC and 1,5 kV DC - Part 0: Principles to be observed in the design
and erection of high voltage installations - Safety of high voltage installations

PROPOSED STABILITY DATE: 2031
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IEC CDV 61936-0 © IEC 2026
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 General requirements for design, construction, operation and maintenance . 14
4.1 General . 14
4.2 Basic requirements during faults . 14
4.3 Danger signs and labelling . 14
4.4 Protection, automation, and auxiliary systems . 15
4.5 Considerations of design to ensure maintainability, constructability, and
operability . 15
5 Protection against electric shock . 15
5.1 General . 15
5.2 Normal conditions . 16
5.3 Single-fault conditions . 16
5.3.1 General . 16
5.3.2 Protection by independent protective provisions . 16
5.4 Protective provisions (elements of protective measures) . 16
5.4.1 General . 16
5.4.2 Protection against direct contact . 17
5.4.3 Protection against indirect contact . 19
5.5 Protective measures . 21
5.5.1 General . 21
5.5.2 Protection by manual disconnection of supply (3.26) . 21
5.5.3 Protection by automatic disconnection of supply (3.4) . 22
5.5.4 Protection by earthed protective equipotential bonding (3.16) . 22
5.5.5 Protection by limiting touch voltage . 22
6 Protection against thermal hazards . 22
6.1 General . 22
6.2 Under Normal operating conditions (3.6.8) . 23
6.2.1 General . 23
6.2.2 Protection against overload under abnormal operating conditions . 23
6.3 Under fault conditions . 23
6.3.1 General . 23
6.3.2 Protection against short circuit currents . 23
6.3.3 Protection against arc faults . 24
6.3.4 Protection against fire hazard . 24
7 Protection against mechanical hazards . 25
7.1 General . 25
7.2 Sources of mechanical stress/load . 26
7.2.1 General . 26
7.2.2 Load cases to be considered for design . 26
7.3 Withstand loads due to arc-faults and explosions . 27
8 Protection against voltage and frequency deviations hazards . 27
8.1 Overvoltage withstand and protection . 27
IEC CDV 61936-0 © IEC 2026
8.2 Undervoltage protection . 27
8.3 Over- and underfrequency . 27
9 Induced potentials to telecommunication and other infrastructure . 27
10 Electric and magnetic fields . 28
Bibliography . 29

Figure 1 – Relationship of IEC 61936-0 to other IEC standards . 5

IEC CDV 61936-0 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Power installations exceeding 1 kV AC and 1,5 kV DC -
Part 0: Principles to be observed in the design and erection of high
voltage installations - Safety of high voltage installations

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for
standardization comprising all national electrotechnical committees (IEC National
Committees).The object of IEC is to promote international co-operation on all questions
concerning standardization in the electrical and electronic fields. To this end and in addition to
other activities, IEC publishes International Standards, Technical Specifications, Technical
Reports,Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National
Committee interested in the subject dealt with may participate in this preparatory
work.International, governmental and non-governmental organizations liaising with the IEC also
participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as
possible, an international consensus of opinion on the relevant subjects since each technical
committee has representation from all interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted
by IEC National Committees in that sense. While all reasonable efforts are made to ensure that
the technical content of IEC Publications is accurate, IEC cannot be held responsible for the
way in which they are used or for any misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC
Publications transparently to the maximum extent possible in their national and regional
publications. Any divergence between any IEC Publication and the corres ponding national or
regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies
provide conformity assessment services and, in some areas, access to IEC marks of
conformity.IEC is not responsible for any services carried out by independent c ertification
bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including
individual experts and members of its technical committees and IEC National committees for
any personal injury, property damage or other damage of any nature whatsoever, whether direct
or indirect, or for costs (including legal fees) and expenses arising out of the publication, use
of, or reliance upon, this IEC Publication or any other IEC publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced
publications is indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve
the use of (a) patent(s). IEC takes no position concerning the evidence, validity or applicability
IEC CDV 61936-0 © IEC 2026
of any claimed patent rights in respect thereof. As of the date of publication of this
document,IEC [had/had not] received notice of (a) patent(s), which may be required to
implement this document. However, implementers are cautioned that this may not repr esent the
latest information, which may be obtained from the patent database available at
https://patents.iec.ch.IEC shall not be held responsible for identifying any or all such patent
rights.
IEC TS 61936-0 This document has been prepared by technical committee 99: Insulation
coordination and system engineering of high voltage electrical power installations above 1,0 kV
AC and 1,5 kV DC. It is a Technical Specification.This XXX edition cancels and replaces the
XXX edition published in [publication_date], Amendment 1:[publication_date] and Amendment
2:[publication_date]. This edition constitutes a technical revision.This edition includes the
following significant technical changes with respect to the previous edition:a) .;b) .The text
of this Technical Specification is based on the following documents:DraftReport on
voting99/XX/DTS99/XX/RVDTSFull 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
Technical Specification is English [change language if necessary].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/publications.A list of all parts in the IEC 61936 (all
parts) [1], published under the general title Power installations exceeding 1 kV AC and 1,5 kV
DC, can be found on the IEC website.The committee has decided that the contents of this
document will remain unchanged until the stability date indicated on the IEC website under
webstore.iec.ch in the data related to the specific document. At this date, the document will
bereconfirmedwithdrawnrevised
IEC CDV 61936-0 © IEC 2026
INTRODUCTION
The scope of TC 99 is the standardisation of insulation co-ordination for high voltage systems
and common rules and particular requirements for system engineering and erection of high
voltage electrical power installations for power generation, transmission, distribution, and
consumer premises, in both indoor and outdoor situations, with particular consideration of
safety aspects.
With the increasing development of electric power systems and renewable energy devices,
there is an increasing demand for Technical Committees to define installations, systems and
equipment at voltages above 1,0 kV AC and 1,5 kV DC.
The objective of this GSP (Group safety publication) is to give the principles for TCs in how to
define requirements with respect to HV installations to ensure that safety of such systems is
maintained and that a consistent approach is taken by all TCs involved with HV installations
with respect to design, operation and maintenance of installation at voltages above 1,0 kV AC
and 1,5 kV DC.
Figure 1 below describes the relationship of this document to other IEC standards:

Figure 1 – Relationship of IEC 61936-0 to other IEC standards
Further reading:
IEC 60038, IEC standard voltages
IEC 60092, Electrical installations in ships
IEC 60417, Graphical symbols for use on equipment, available at https://std.iec.ch/iec60417
IEC 60990, Methods of measurement of touch current and protective conductor current
IEC 61892 (all parts), Mobile and fixed offshore units - Electrical installations
IEC 63042 (all parts), UHV AC transmission systems
B3/CIRED Technical Brochure Substation earthing system design optimisation through the
application of quantified risk analysis Reference: 749, 2018
Norwegian “Regulations on electrical supply installations”, 2006
CIGRE Technical Brochure 391 “Guide for measurement of radio frequency interference from
HV and MV substations”
CIGRE Technical Brochure 535 “EMC within power plants and substations”
IEC CDV 61936-0 © IEC 2026
1 Scope
This document provides principles to ensure the coherence amongst HV publications to be
observed necessary for the coordination of the design, selection of equipment, operation, and
maintenance activities for erection of electrical HV installations to ensure the safety of such
systems.
In the context of this document, "safety" relates to the safety of persons, domestic animals,
livestock and safe protection of equipment and property.
This GROUP SAFETY PUBLICATION focusing on safety essential requirements is primarily
intended to be used as a SAFETY STANDARD for the installations mentioned in the scope, but
is also intended to be used by TCs in the preparation of publications for instal lations similar to
those mentioned in the scope of this GROUP SAFETY PUBLICATION, in accordance with the
principles laid down in IEC Guide 104 and lSO/lEC Guide 51.
One of the RESPONSIBILITIES of a TC is, wherever applicable, to make use of BSPs and/or
GSPs in the preparation of its publications.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
ISO/lEC Guide 51:2014, Safety aspects - Guidelines for their inclusion in standards
IEC 60068 (all parts), Environmental testing
IEC 60071 (all parts), Insulation co-ordination
IEC 60445, Basic and safety principles for man-machine interface, marking and identification -
Identification of equipment terminals, conductor terminations and conductors
IEC TR 60479-5, Effects of current on human beings and livestock - Part 5: Touch voltage
threshold values for physiological effects
IEC 60529, Degrees of protection provided by enclosure (IP Code)
IEC 60721 (all parts), Classification of environmental conditions
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at https://www.electropedia.org/
3.1
arc
arcing
IEC CDV 61936-0 © IEC 2026
luminous discharge of electricity across an insulating medium, usually accompanied by the
partial volatilization of the electrodes
Note 1 to entry: A complete sinusoidal current half-cycle is not considered to be an arcing half-cycle.
[SOURCE: IEC 60050-442:1998/AMD3:2019, 442-05-65]
3.2
arc fault
arcing fault
dangerous unintentional arc
[SOURCE: IEC 60050-442:1998/AMD3:2019, 442-05-66]
3.3
arm's reach
zone of accessibility to touch extending from any point on a surface where persons usually
stand or move about to the limits which a person can reach with the hand, in any direction,
without assistance
[SOURCE: IEC 60050-195:2021, 195-06-12, modified - The note has been removed.]
3.4
automatic disconnection of supply
interruption of one or more of the line conductors effected by the automatic operation of a
protective device in the event of a fault
Note 1 to entry: This does not necessarily mean an interruption in all conductors of the supply system.
[SOURCE: IEC 60050-195:2021, 195-04-10, modified - “in the event of a fault” replaces “in case
of a fault” and Note 1 to entry added]
3.5
basic insulation
insulation (3.22) that provides protection against direct contact
Note 1 to entry: This concept does not apply to insulation (3.22) used exclusively for functional purposes.
[SOURCE: IEC 60050-195:2021, 195-06-06 modified: replaced basic protection with protection
against direct contact]
3.6
conditions
3.6.1
normal condition
a state in which:
– there are no faults that can cause a risk of electric shock; and
– all protective provisions are intact; and
– operation is in accordance with the intended use.

Note 1 to entry: Note: “operation in intended use”; see 3.6 of ISO/IEC Guide 51:2014.
IEC CDV 61936-0 © IEC 2026
3.6.2
single fault condition
state in which one accidental conductive path is present
between hazardous-live-part and accessible-conductive-part, which could cause a risk of
electric shock
Note 1 to entry: If a single fault condition results in one or more other fault conditions, all are considered as one
single fault condition.
3.6.3
fault condition
state in which one accidental conductive path is present
between two or more conductive parts
[SOURCE: 60909 Def 3.1]
3.6.4
environmental condition
set of characteristic of the environment which may affect performance of a component, device
or equipment
Note 1 to entry: Examples of environmental conditions are external influences, characteristics of the power supply,
duty cycle or duty type.
[SOURCE: IEC 60050-151:2001, 151-16-01 modified - The term “operating conditions” has
been replaced by “environmental condition”. It has also been replaced by “environmental
conditions” in Note 1 to entry.]
3.6.5
normal environmental condition
set of characteristic of the environment which may affect performance of a device or system,
and which is standardized as normal
Note 1 to entry: Examples of environmental conditions are pressure, temperature, humidity, radiation, vibration.
Note 2 to entry: Conditions which are normal as described in IEC Guide 111:2004 [1].
[SOURCE: IEC 60050-151:2001, 151-16-03, modified - The words “and which is standardized
as normal” have been added.]
3.6.6
special environmental condition
set of characteristic of the environment which may affect performance of a device or system,
and which is standardized as special
Note 1 to entry: Examples of environmental conditions are pressure, temperature, humidity, radiation, vibration.
Note 2 to entry: Condition which is special as described in IEC Guide 111.
Note 3 to entry: See 5.3 of IEC Guide 111:2004 for more information on special environmental conditions.
3.6.7
operating condition
state of a component, device, equipment or system characterized by one or more properties
3.6.8
normal operating condition
operating condition (3.6.7) representing the range of intended use (3.6.10)
IEC CDV 61936-0 © IEC 2026
[SOURCE: IEC 60050-903:2013/AMD1:2014, 903-01-21 modified - “as closely as possible” has
been removed, as well as ““that can reasonably be expected” and “normal use” has been
replaced by “intended use”.]
3.6.9
abnormal operating condition
operating condition (3.6.7) that is not a normal operating condition (3.6.8) and is not a single
fault condition of the equipment itself
[SOURCE: IEC 60050-903/AMD1:2014:2013, 903-01-22]
3.6.10
intended use
use of a product, process or service in accordance with the information for use
[SOURCE: IEC 60050-903:2014, 903-01-13, modified - The words “provided by the supplier”
have been removed.]
3.7
danger zone
in the case of HV, area limited by the minimum clearance around live-parts without complete
protection against direct contact
Note 1 to entry: Entering the danger zone is considered the same as touching live-parts.
[SOURCE: IEC 61140:2016 [2], 3.35 modified - In Note 1 to entry, “hazardous-live-parts” has
been replaced by “live-parts”. Added "against direct contact".]
3.8
minimum clearance
N
clearance which describes the area of danger zone
[SOURCE: IEC 61936-1:2021, 3.5.6, modified - “hazardous” and “around live-parts without
complete protection against direct contact” have been removed, as well as the two notes.]
3.9
vicinity zone
limited space outside the live working zone where specific precautions are taken to avoid
encroaching into the live working zone
Note 1 to entry: Encroaching into the live working zone will create an electrical hazard.
Note 2 to entry: The outer boundary of the vicinity zone and the specific precautions that apply are generally defined
by national or company regulations.
Note 3 to entry: This entry was numbered 651-01-07 in IEC 60050-651:1999. It has been modified as follows:
Greater detail is provided regarding the precautions to be taken when in the vicinity zone.
[SOURCE: IEC 60050-651:2014, 651-21-04]
3.10
reference earth
reference ground, US
part of the Earth considered as conductive, the electric potential of which is conventionally
taken as zero, being outside the zone of influence of any earthing arrangement
Note 1 to entry: The concept “Earth” means the planet and all its physical matter.
IEC CDV 61936-0 © IEC 2026
[SOURCE: IEC 60050-195:2021, 195-01-01]
3.11
earth, verb
ground, verb (US)
to make an electrical connection between a conductive part and a local earth
Note 1 to entry: The connection to local earth can be:

– intentional; or
– unintentional or accidental
and can be permanent or temporary.

[SOURCE: IEC 60050-195:2021, 195-01-08]
3.12
local earth
local ground (US)
part of the Earth which is in electric contact with an earth electrode and the electric potential of
not necessarily equal to zero
[SOURCE: IEC 60050-195:2021, 195-01-03]
3.13
earthing arrangement
grounding arrangement (US)
all the electrical means involved in the earthing of a system, installation or equipment
Note 1 to entry: Electric connection and devices used for earthing are examples of electrical means.
[SOURCE: IEC 60050-195:2021, 195-02-20]
3.14
earthing conductor
grounding conductor (US)
conductor which forming a conductive path between a conductive part and an earth electrode
EXAMPLE A conductor connected between a main earthing terminal or busbar and an earth electrode.
[SOURCE: IEC 60050-195:2021, 195-02-03]
3.15
earth electrode
ground electrode (US)
conductive part that is in electric contact with local earth, directly or through an intermediate
conductive medium
[SOURCE: IEC 60050-195:2021, 195-02-01]
3.16
earthed protective-equipotential-bonding
protective-equipotential-bonding connected to local earth
3.17
equipotential bonding
set of electric connections intended to achieve equipotentiality between conductive parts
IEC CDV 61936-0 © IEC 2026
Note 1 to entry: The effectiveness of the equipotential bonding may depend on the frequency of the current in the
bonding.
[SOURCE: IEC 60050-195:2021, 195-01-10, modified - Note 1 to entry added]
3.18
exposed-conductive-part
conductive part of equipment that can be touched and which is not live under normal conditions,
but that can become live when basic insulation fails
Note 1 to entry: A conductive part of electrical equipment which can become live only through contact with an
exposed-conductive-part which has become live, is not considered to be an exposed-conductive-part itself.
[SOURCE: IEC 60050-195:2021, 195-06-10 modified - Note 1 to entry added]
3.19
extraneous-conductive-part
conductive part not forming part of the electrical installation and that is likely to introduce an
electric potential, generally the electric potential of a local earth
[SOURCE: IEC 60050-195:2021, 195-06-11]
3.20
global earthing system
equivalent earthing system created by the interconnection of local earthing systems that
ensures, by the proximity of the earthing systems, that there are no dangerous touch voltages
Note 1 to entry: Such systems permit the division of the earth fault current in a way that results in a reduction of
the earth potential rise at the local earthing system. Such a system could be said to form a quasi -equipotential
surface.
Note 2 to entry: The existence of a global earthing system may be determined by sample measurements or
calculation for typical systems. Typical examples of global earthing systems are in city centres; urban or industrial
areas with distributed low- and high-voltage earthing.
[SOURCE: IEC 61936-1:2021 3.7.19]
3.21
instructed person
electrically instructed person
person adequately advised or supervised by electrically skilled persons to enable him or her to
perceive risks and to avoid hazards which electricity can create
[SOURCE: IEC 60050-195:2021, 195-04-02]
3.22
insulation
set of properties which characterize the ability of an insulation to provide its function
Note 1 to entry: Examples of relevant properties are: resistance, breakdown voltage.
Note 2 to entry: Insulation can be a solid, a liquid or a gas (e.g. air), or any combination.
[SOURCE: IEC 60050-151:2001, 151-15-42, modified - Note 2 to entry has been added]
3.23
insulation coordination
selection of the dielectric strength of equipment in relation to the operating voltages and
overvoltages which can appear on the system for which the equipment is intended, and taking
into account the service environment and the characteristics of the available preventing and
protective devices
IEC CDV 61936-0 © IEC 2026
[SOURCE: IEC 60050-614:2016, 614-03-08]
3.24
live part
conductive part intended to be energized in normal operating conditions, including a neutral
conductor or mid-point conductor
Note 1 to entry: This concept does not necessarily imply a risk of electric shock.
[SOURCE: IEC 60050-195:2021, 195-02-19, modified - “under normal operating conditions,
including the neutral conductor and mid-point conductor, but excluding the PEN conductor, PEM
conductor and PEL conductor” has been replaced with “normal operating conditions, including
a neutral conductor or mid-point conductor”. Note 1 to entry has been added.”]
3.25
main contact
contact included in the main circuit of a mechanical switching device, intended to carry, in the
closed position, the current of the main circuit
[SOURCE: IEC 60050-441:1984, 441-15-07]
3.26
manual disconnection of supply
interruption of one or more of the line conductors effected by the manual operation of an
operating person in the event of a fault
3.27
ordinary person
person who is neither a skilled person nor an instructed person
[SOURCE: IEC 60050-195:2021, 195-04-03]
3.28
overvoltage
voltage:
– between one phase conductor and earth or across a longitudinal insulation having a peak
value exceeding the peak of the highest voltage of the AC-system divided by
√3 or;
– between phase conductors having a peak value exceeding the amplitude of the highest
voltage of the AC-system;
– voltage having a value exceeding the corresponding highest steady state voltage of the DC -
system.
[SOURCE: IEC 60050-614:2016, 614-03-10, modified - The specific use system> has been removed. In the first dash, “line” has been replaced with “phase” and “of the
AC-system” has been added; in the second dash: “of the AC-system” has been added and the
last dash has been added.]
3.29
potential grading
control of the local earth potential, especially the earth surface potential,
by means of earth electrodes
[SOURCE: IEC 61140:2016 3.34]
IEC CDV 61936-0 © IEC 2026
3.30
protective barrier
part providing protection against contact by a human being or livestock with a live
part from any usual direction of access
[SOURCE: IEC 60050-195:2021, 195-06-15, modified - "human being or livestock with
hazardous-live-parts" has been replaced with "human or livestock with a live part"]
3.31
protective-equipotential-bonding
equipotential bonding for the purposes of electrical safety
[SOURCE: IEC 60050-195:2021, 195-01-15]
3.32
protective obstacle
part preventing unintentional contact by a human or livestock with a live part, but
not preventing such contact by deliberate action
[SOURCE: IEC 60050-195:2021, 195-06-16, modified - “with hazardous-live-parts” has been
replaced by “with a live part”.]
3.33
protective measure
appropriate combination of protective provisions
[SOURCE: IEC 60050-195:2021, 195-06-26]
3.34
protective provision
independent provision intended to protect against electric shock under specified conditions
Note 1 to entry: The provision may be a means or technique or device or process.
[SOURCE: IEC 60050-195:2021, 195-06-25, modified - Note 1 to entry has been added.]
3.35
short-circuit current
current flowing at a given point of a network resulting from a short circuit at another point of
this network
[SOURCE: IEC 60050-603:1986, 603-02-26]
3.36
skilled person
electrically skilled person
person with relevant education and experience to enable him or her to perceive risks and to
avoid hazards which electricity can create
[SOURCE: IEC 60050-195:2021, 195-04-01]
3.37
step voltage
voltage between two points on the Earth's surface
Note 1 to entry: Typically, a distance of 1 m between the two points is considered to be the stride length of a person.
IEC CDV 61936-0 © IEC 2026
[SOURCE: IEC 60050-195:2021, 195-05-12, modified - The term “human being” has been
replaced by “person”.]
3.38
thermal hazard
harm caused by high or low temperatures in, near or on electrical equipment
3.39
touch voltage
voltage between conductive parts when touched simultaneously by a human being
or livestock
Note 1 to entry: The value of the effective touch voltage is influenced by the impedance of the human being or the
livestock in electric contact with these conductive parts.
[SOURCE: IEC 60050-195:2021, 195-05-11]
3.40
undervoltage
voltage between phase conductors having a value below the lowest voltage of the installation
for correct operation or preventing damage to equipment
4 General requirements for design, construction, operation and maintenance
4.1 General
Electrical HV installations shall be designed, constructed and be able to be operated and
maintained such that they fulfil their intended function with necessary protection against electric
shock, burns and thermal effects of persons, livestock and property when used according to the
intended use and for reasonably foreseeable misuse.
Installations shall be constructed and secured such that operations and maintenance can be
performed in a manner that do not cause harm to persons, the public and the surroundings.
Necessary safety equipment should be accessible.
Installations and their equipment shall be suitable for the stresses to which they may be
exposed and for the surrounding in which they shall operate.
The requirements regarding risk management in ISO/IEC Guide 51 shall be met in the process
for establishing the requirements in HV-standards.
NOTE The ISO/IEC 31000 series and the ISO/IEC 31010 series give guidelines for risk management for the user
of the standards.
Clause 5 to Clause 10 of this document give principles to be adopted for the safe design of HV
installations.
4.2 Basic requirements during faults
Electrical installations shall be designed, constructed such that protection against hazards is
ensured under normal conditions and under credible single fault conditions or a single
erroneous operation. Faults shall be managed or corrected.
4.3 Danger signs and labelling
Installations shall have danger signs, labelling and identification, such that erroneous operation
and accidents are prevented. Danger signs, labelling and identification shall be durable, clear,
readily visible.
IEC CDV 61936-0 © IEC 2026
4.4 Protection, automation, and auxiliary systems
Installations shall have protection systems and should have auxiliary systems and equipment
for monitoring, automation and control which are necessary for safety and carrying out
operations and maintainance.
4.5 Considerations of design to ensure maintainability, constructability, and
operability
The design of electrical power installations shall take into account the work activities that may
be undertaken to ensure maintainability in addition to constructability and operability of
electrical power installations.
The methods of working in the live working zone, in the vicinity zone or dead working shall be
able to be performed in a proper manner.
The values for the minimum clearance of danger zone in AC installations are given in Tables 2
and 3 (N ) in IEC 61936-1:2021. These values can be used to define clearances in the design
of installations and for working. It describes the area of danger zone around live parts without
complete protection against direct contact.
Working distances may be determined based upon minimum clearance of danger zone, taking
into consideration overvoltage conditions and ergonomic factors (e.g. considerations of
inadvertent movements (full or expected reach) of persons, tools, equipment, veh icles and
conductors).
NOTE Requirements for DC installations are under consideration.
5 Protection against electric shock
5.1 General
This Clause 5 is limited to installations up 1 000 Hz.
Electric shock is defined as the physiological effect resulting from an electric current passing
through a human body or livestock. The physiological effect can be harmful (such as ventricular
fibrillation, burns, asphyxiation), or non-harmful (such as muscular reaction, perception).
Live-parts shall not be accessible and accessible conductive parts shall not become hazardous,
either:
– under normal conditions (under intended use, see 3.6 of ISO/IEC Guide 51:2014, and
absence of a fault); or
– under single-fault conditions.
NOTE The accessibility rules for ordinary persons can differ from those for skilled or instructed persons and can
also vary for different products and locations.
Protection under normal conditions is provided by basic protection.
Protection under single-fault conditions is provided by fault protection.
___________
Clause 5 is based on the basic safety publicationIEC 61140:2016. The use of indirect and direct contact terms
are added for application in the HV installations.
IEC CDV 61936-0 © IEC 2026
5.2 Normal conditions
To meet the fundamental rule for protection against electric shock under normal conditions,
basic protection, as specified in this document, is necessary.
The requirements for provisions for basic protection are given in 5.4.2.
5.3 Single-fault conditions
5.3.1 General
Single faults shall be considered, if they would:
– cause an accessible conductive part which is not energized under normal conditions to
become energized (e.g. due to failure of basic insulation to exposed-conductive-parts or
extraneous-conductive-parts).
To meet the fundamental rule under single-fault conditions, fault protection is necessary. This
protection shall be achieved by a further protective provision, independent of that for basic
protection.
5.3.2 Protection by independent protective provisions
Each of the independent protective provisions shall be designed so that a failure is unlikely
under conditions specified by the relevant technical committee.
The independent protective provisions shall have no influence on each other such that a failure
of one of the protective provisions could impair another.
Simultaneous failure of independent protective provisions is unlikely and need not normally be
taken into consideration. Reliance is placed on the unaffected protective provisions remaining
effective.
5.4 Protective provisions (elements of protective measures)
5.4.1 General
5.4.1 to 5.4.2.9 give an overview of the different protective provisions. Protective measures
result from a suitable combination of them. The structure of typical protective measures is
described in 5.5.
All protective provisions shall be designed and constructed to be effective during the anticipated
lifetime of the installation, of the system or of the equipment when used as intended and
properly maintained.
The environment shall be taken into account by use of the classification of external influences
as described in the IEC 60721 series and for testing in the IEC 60068 series. Attention is
particularly drawn to the ambient temperature, climatic conditions, presence of water,
mechanical stresses, capability of persons and area of contact of persons or livestock with local
earth potential.
Technical committees shall take account of the requirements for insulation coordination. For
high-voltage installations, systems and equipment, the requirements are found in the IEC 60071
series.
IEC CDV 61936-0 © IEC 2026
5.4.2 Protection against direct contact
5.4.2.1 General
Installations shall be such that they prevent unintentional infringement of the danger zone (3.7)
and prevent structures/accessible parts to be energized due to capacitive or inductive coupling,
or high earth currents under normal conditions (3.6.1).
The following provisions for basic protection are recognized.
To prevent unintentional infringement of the danger zone (3.7):
– protection by enclosure;
– protection by barrier;
– protection by obstacle;
– protection by placing out of arms reach;
To prevent structures and accessible parts to be energized due to capacitive or inductive
coupling, or high earth currents under normal conditions (3.6.1):
– bonding extraneous-conductive-parts to each other, and/or to the earthing arrangement
(capacitive or inductive coupling); or
– potential grading (3.29).
5.4.2.2 Basic insulation (3.5)
Where basic insulation is provided by air, access to live parts or entering the danger zone shall
be prevented by obstacles, protective barriers or enclosures as specified in 5.4.2.3 and 5.4.2.4
or by placing out of
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