IEC TR 61200-52:2013
(Main)Electrical installation guide - Part 52: Selection and erection of electrical equipment - Wiring systems
Electrical installation guide - Part 52: Selection and erection of electrical equipment - Wiring systems
IEC/TR 61200-52:2013 is Technical Report which serves as a supplement to IEC 60364-5-52:2009 and explains the rules so as to facilitate the design, selection, erection and maintenance of wiring systems. It follows the numbering of that standard. This technical report is written for everyone concerned with the design, the selection and supply of equipment, as well as the persons who install, maintain and use electrical installations. This second edition cancels and replaces the first edition, published in 1993, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- guidance associated with conduit systems, cable ducting systems, cable trunking systems, cable tray systems and cable ladder systems has been added giving, for example, recommended maximum straight lengths of conduit to ease the installation circuit wiring;
- guidance associated with selection and erection of wiring systems in relation to external influences has been extended to cover impact, and other mechanical stresses;
- guidance for grouping of cables has been added; and
- guidance on maximum temperatures of terminals in normal service conditions has been extended.
Guide pour les installations électriques - Partie 52: Choix et mise en oeuvre des matériels électriques - Canalisations
La CEI/TR 61200-52:2013 est un Rapport Technique qui constitue un supplément à la CEI 60364-5-52:2009 et explique les règles de manière à faciliter la conception, le choix, la mise en oeuvre et la maintenance des canalisations. Sa numérotation des articles suit la numérotation de la CEI 60364-5-52. Il est rédigé à l'intention de toute personne concernée par la conception, le choix et la fourniture des matériels, ainsi qu'à l'intention des personnes qui installent, assurent la maintenance et utilisent des installations électriques. Cette deuxième édition annule et remplace la première édition, parue en 1993, et constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- des recommandations concernant les systèmes de conduits, systèmes de conduits-profilés, systèmes de goulottes, systèmes de chemins de câbles et systèmes d'échelles à câbles ont été ajoutées pour donner, par exemple, les longueurs maximales recommandées pour les conduits afin de faciliter l'installation des circuits;
- les recommandations pour le choix et la mise en oeuvre des canalisations en tenant compte des influences externes ont été étendues aux impacts et autres contraintes mécaniques;
- des recommandations pour les groupements de câbles ont été ajoutées; et
- des recommandations sur les températures maximales des bornes en conditions de fonctionnement normal ont été étendues.
General Information
Standards Content (sample)
IEC/TR 61200-52
Edition 2.0 2013-07
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
Electrical installation guide –
Part 52: Selection and erection of electrical equipment – Wiring systems
Guide pour les installations électriques –
Partie 52: Choix et mise en œuvre des matériels électriques – Canalisations
IEC/TR 61200-52:2013
---------------------- Page: 1 ----------------------
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contactez-nous: csc@iec.ch.---------------------- Page: 2 ----------------------
IEC/TR 61200-52
Edition 2.0 2013-07
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
Electrical installation guide –
Part 52: Selection and erection of electrical equipment – Wiring systems
Guide pour les installations électriques –
Partie 52: Choix et mise en œuvre des matériels électriques – Canalisations
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX M
ICS 29.060.01; 91.140.50 ISBN 978-2-8322-0882-3
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical CommissionMarque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – TR 61200-52 © IEC:2013
CONTENTS
FOREWORD ........................................................................................................................... 3
520 Introduction ................................................................................................................. 5
520.1 Scope .............................................................................................................. 5
520.2 Normative references ....................................................................................... 5
521 Types of wiring system ................................................................................................ 6
521.6 Conduit systems, cable ducting systems, cable trunking systems, cabletray systems and cable ladder systems ............................................................ 6
522 Selection and erection of wiring systems in relation to external influences ................... 7
522.4 Presence of solid foreign bodies ...................................................................... 7
522.6 Impact .............................................................................................................. 7
522.8 Other mechanical stresses ............................................................................... 7
522.8.101 Reduction of the risk of short-circuit or earth fault ........................ 7
522.11 Solar radiation and ultraviolet radiation ............................................................ 7
523 Current-carrying capacities .......................................................................................... 8
526 Electrical connections .................................................................................................. 8
526.4 Maximum temperatures of terminals in normal service conditions ..................... 8
526.4.101 General ....................................................................................... 8
526.4.201 Limitation of temperature at a terminal ......................................... 8
526.4.301 Limitation of the effects of temperature at a terminal innormal service ............................................................................. 9
526.8 Connection of multiwire, fine wire and very fine wire conductors .................... 10
528 Proximity of wiring systems to other services ............................................................. 10
528.2 Proximity of communication cables................................................................. 10
Annex B, Current-carrying capacity ....................................................................................... 11
Annex I (informative) List of notes concerning certain countries ............................................ 12
Bibliography .......................................................................................................................... 13
Table 52A – Cable surrounded by thermal insulation ............................................................ 11
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSTALLATION GUIDE –
Part 52: Selection and erection of electrical equipment –
Wiring systems
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
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".IEC 61200-52, which is a technical report, has been prepared by IEC technical
committee 64: Electrical installations and protection against electric shock.
This second edition cancels and replaces the first edition, published in 1993, and constitutes
a technical revision.This edition includes the following significant technical changes with respect to the previous
edition:---------------------- Page: 5 ----------------------
– 4 – TR 61200-52 © IEC:2013
a) the scope has been modified; whilst the Guide does not form part of the IEC 60364 series,
it serves as a supplement to IEC 60364-5-52:2009 and explains the rules so as to facilitate
the design, selection, erection and maintenance of wiring systems;b) guidance associated with conduit systems, cable ducting systems, cable trunking systems,
cable tray systems and cable ladder systems has been added giving, for example,recommended maximum straight lengths of conduit to ease the installation circuit wiring;
c) guidance associated with selection and erection of wiring systems in relation to external
influences has been extended to cover impact, and other mechanical stresses.d) guidance for grouping of cables has been added.
e) guidance on maximum temperatures of terminals in normal service conditions has been
extended;f) guidance on the connection of multi wire, fine wire and very fine wire conductors has been
added;g) guidance on proximity of communication cables has been added;
h) guidance on cables in contact with thermal insulation has been added.
This technical report serves as a supplement to IEC 60364-5-52:2009 and follows the
numbering of that standard.The text of this technical report is based on the following documents:
Enquiry draft Report on voting
64/1875/DTR 64/1887/RVC
Full information on the voting for the approval of this technical report 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.
The committee has decided that the contents of this publication will remain unchanged until
the stability 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.
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TR 61200-52 © IEC:2013 – 5 –
ELECTRICAL INSTALLATION GUIDE –
Part 52: Selection and erection of electrical equipment –
Wiring systems
520 Introduction
520.1 Scope
This Technical Report serves as a supplement to IEC 60364-5-52:2009 and explains the rules
so as to facilitate the design, selection, erection and maintenance of wiring systems.
It is written for everyone concerned with the design, the selection and supply of equipment, as
well as the persons who install, maintain and use electrical installations.520.2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including anyamendments) applies.
IEC 60227-4, Polyvinyl chloride insulated cables of rated voltages up to and including
450/750 V – Part 4: Sheathed cables for fixed wiringIEC 60245-4, Rubber insulated cables – Rated voltages up to and including 450/750 V –
Part 4: Cords and flexible cablesIEC 60364-4-43:2008, Low-voltage electrical installations – Part 4-43 Protection for safety –
Protection against overcurrentIEC 60364-5-51:2005, Electrical installations of buildings – Part 5-51: Selection and erection
of electrical equipment – Common rulesIEC 60364-5-52:2009, Low-voltage electrical installations – Part 5-52: Selection and erection
of electrical equipment – Wiring systemsIEC 60502-1, Power cables with extruded insulation and their accessories for rated voltages
from 1 kV (U = 1,2 kV) up to 30 kV (U = 36 kV) – Part 1: Cables for rated voltages of 1 kV
m m(U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
IEC/TR 60890, A method of temperature-rise assessment by extrapolation for partially type-
tested assemblies (PTTA) of low-voltage switchgear and controlgearIEC/TR 60943, Guidance concerning the permissible temperature rise for parts of electrical
equipment, in particular for terminalsIEC 61084 (all parts), Cable trunking and ducting systems for electrical installations
IEC 61084-2-2, Cable trunking and ducting systems for electrical installations – Part 2-2:
Particular requirements – Cable trunking systems and cable ducting systems intended for
underfloor and flushfloor installations---------------------- Page: 7 ----------------------
– 6 – TR 61200-52 © IEC:2013
IEC 61386 (all parts), Conduit systems for cable management
IEC 61386-21, Conduit systems for cable management – Part 21: Particular requirements –
Rigid conduit systemsIEC 61386-22, Conduit systems for cable management – Part 22: Particular requirements –
Pliable conduit systemsIEC 61386-23, Conduit systems for cable management – Part 23: Particular requirements –
Flexible conduit systemsIEC 61439 (all parts), Low-voltage switchgear and controlgear assemblies
521 Types of wiring system
521.6 Conduit systems, cable ducting systems, cable trunking systems, cable tray
systems and cable ladder systems
The following includes recommendations to ease the installation, or replacement, of circuits
installed in conduit.a) Straight conduit lengths between access points should not exceed 25 m. Conduit lengths
which include changes in direction should not exceed 15 m between access points. There
should be no more than three changes in direction between access points.b) The number of bends in any run should be minimized.
c) Any bending radius should be as large as possible and in accordance with the
manufacturer's instructions.
d) The cables or insulated conductors should not occupy more than one-third of the total
internal cross-sectional area of the conduit.e) Conduit systems should be installed so as to minimize the mechanical stress on the
conduit.f) If conduit systems are to be installed outdoors, consideration should be given to the
ambient temperature and effects of solar radiation as indicated in 522.1 and 522.11.
g) Where self-recovering conduit has to be embedded in concrete, consideration should be
given to the possibility of permanent deformation of the cross-section of the conduit that
might result in damage to the enclosed cables or insulated conductors. Where necessary,
measures should be taken such as additional mechanical protection or the use of conduit
having suitably increased diameter or resistance to compression.When electrical accessories are mounted in trunking or ducting systems that are installed in
or under a floor, the type of floor treatment likely to be used (wet or dry) should be taken into
consideration.Where cable trunking systems are installed in a skirting position (e.g. Item 6 of Table A52.3 of
IEC 60364-5-52:2009), damage caused by the ingress of water can be avoided by placing the
insulated conductors laid within at least 10 mm above the floor level.Cable trunking systems and cable ducting systems intended for underfloor and flushfloor
installations are covered by IEC 61084-2-2.Where cable tray systems are used, the use of a cover can also be necessary, for example for
mechanical protection or design reasons or preventing access (e.g. in the basin of public
fountains).---------------------- Page: 8 ----------------------
TR 61200-52 © IEC:2013 – 7 –
522 Selection and erection of wiring systems in relation to external
influences
522.4 Presence of solid foreign bodies (AE)
Cable management systems will not protect against ingress of solid foreign bodies unless they
comply with a protection degree at least IP2X.522.6 Impact
Trunking, ducting and conduit systems provide mechanical protection to the cable, but cable
tray and cable tray with cover might not provide such mechanical protection, as, according to
the product standard, they are not tested for this purpose.522.8 Other mechanical stresses (AJ)
522.8.101 Reduction of the risk of short-circuit or earth fault
Where devices for short-circuit protection are placed in accordance with 434.2.1 of
IEC 60364-4-43:2008, it is required that the conductors shall be installed so as to reduce the
risk of a short-circuit to a minimum.This implies that conductor arrangements should be made so as to minimize the risk of
contact between the conductors and contact of live conductors with earthed parts and to
provide protection against damage due to external influences (e.g. mechanical damage).
Examples of such arrangements are as follows:a) Arrangement consisting of single-core cables in accordance with IEC 60502-1, single-core
non-metallic sheathed cables in accordance with IEC 60227-4 or single-core rubber
insulated and sheathed flexible cables in accordance with IEC 60245-4 and where the risk
of mechanical damage is prevented.b) Cables and rubber-insulated and sheathed flexible cables laid so that they are accessible
but not in the vicinity of combustible materials and where the risk of mechanical damage is
prevented.c) Cables with non-metallic sheath installed in rigid, flexible or pliable conduits in accordance
with IEC 61386-21, IEC 61386-22 or IEC 61386-23.d) Cables with non-metallic sheath installed in trunking or ducting systems in accordance
with the IEC 61084 series.With regard to safety, an arrangement of cables or insulated conductors which could burn out
without endangering their environment (e.g. buried cables) is considered to be equivalent to a
circuit installed so as to reduce the risk of a short-circuit to a minimum.522.11 Solar radiation (AN) and ultraviolet radiation
Where wiring systems are installed outdoors, particular attention should be given to the
effects of solar radiation. The two main effects to be considered are the heating effects and
the UV stability. As indicated in 512.2.2 of IEC 60364-5-51:2005 and Table 51A of that
standard, if the product does not, by its construction, have the characteristics relevant to the
external influences of its location, it may nevertheless be used on condition that it is provided
with appropriate additional protection in the erection of the installation, such as interposition
of screens.NOTE The IEC 60287 [1] series gives a method for determining the current-carrying capacity in case of solar
radiation.Figures in square brackets refer to the Bibliography.
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– 8 – TR 61200-52 © IEC:2013
523 Current-carrying capacities
The current-carrying capacity of a cable is affected by the type of insulation material of the
cable, ambient temperature, installation method, grouping and presence of thermal insulation.
See the NOTE in 522.11.Annex B of IEC 60364-52:2009 includes tabulated reduction factors for a limited number of
circuits. Increasing the number of circuits in a group (conductors within a single installation
method) will require further reduction in the current-carrying capacity of those conductors
(smaller reduction factors than specified for the maximum number of circuits or conductors),
due to increased heating effects. Because of this, it is recommended that such groups, with
more circuits or conductors than the maximum indicated in the tables, be divided into smaller
groups of circuits or conductors with spacing provided between the groups.526 Electrical connections
526.4 Maximum temperatures of terminals in normal service conditions
526.4.101 General
The temperature of a terminal is the sum of the ambient temperature and its temperature rise
in normal service.Product standards give conventional limit values for temperature rise under defined test
conditions. For installation conditions that differ from the defined test conditions, rating factors
may need to be applied and guidance should be obtained from the manufacturer. Relevant
standards in this respect are the IEC 61439 series and IEC 60890.The temperature at a terminal is affected by the heat dissipated in normal service by the
equipment. This heat may be caused by internal losses dissipated in the equipment and by
neighbouring internal and external heat sources, if any. A possible external heat source is the
cable of the wiring system connected to the terminal equipment.Compatibility between the temperature achieved at the terminals of equipment and the
temperature permitted for the insulation of the conductors and cables should be obtained by
appropriate arrangement during design/installation.Current-carrying capacities of conductors, the values of which are tabulated in
IEC 60364-5-52, are calculated so that the temperature on the cores does not exceed the
permissible temperature determined by the selection of the insulation. These current-carrying
capacities do not take account of any temperature rise at a termination.526.4.201 Limitation of temperature at a terminal
It is necessary to limit the temperature at a terminal so that the maximum steady-state or
peak temperature limits of the insulation of the conductors connected to the terminal and of
any insulating material used to support the connection are not exceeded. The temperature at
a terminal can be limited by one or more of the following measures:a) Limitation of contents of enclosures (cubicles, cabinets, trunkings, conduits). The
limitation of contents of trunkings and conduits is recommended when a large number of
circuits issue from the same panel; in this case it is preferable to divide the circuits
between several runs of trunking or conduit.b) Spacing between equipment in order to improve natural ventilation. Spacing between
adjacent equipment permits better dissipation of heat. It is necessary to refer to the
manufacturer's instructions. This solution is especially recommended when a great
number of items of equipment are installed in the same enclosure (cubicle or cabinet).
---------------------- Page: 10 ----------------------TR 61200-52 © IEC:2013 – 9 –
c) Appropriate arrangement of equipment dissipating heat inside enclosures. It is
recommended that equipment dissipating heat is installed in an appropriate way so that
the correct operation of other equipment will not be impaired. Other means, such as the
interposition of screens or deflectors, may be used for this purpose.d) Natural or forced ventilation or air-conditioning of cubicles, cabinets or locations. Forced
ventilation of the equipment may be necessary, for reasons other than cooling, in specific
applications, for example to protect against ingress of dust.e) Derating of equipment by use of equipment having higher rated current, consequently
dissipating less heat. Derating of equipment can be used to reduce the temperature of
terminals, provided that such derating is permitted for the equipment.f) Selection of material for enclosures of cubicles or cabinets in which terminals are installed
in order to improve the thermal dissipation. Thin metallic enclosures will dissipate heat
more readily than thick walled enclosures manufactured from insulation materials.
g) Maintenance of correct clamping of conductors in the terminals. Arrangements should be
made to ensure the maintenance of clamping pressure of conductors in their terminals.
Such arrangements may be built in (for example, use of resilient connections) or result
from instructions for the inspection of the installation.h) Introduction of an intermediate terminal (of the appropriate rated operating temperature)
outside the current-using equipment enables a conductor of larger cross-sectional area or
a higher temperature type of cable to be connected.i) Where cables that are permitted to run at a temperature exceeding 70 °C (such as cross-
linked insulated cables) are connected to equipment or accessories designed to operate
at a temperature not exceeding 70 °C, the conductor size should be chosen based on the
current ratings for 70 °C cables of a similar construction.j) Separation of conductors of multicore cables between the end of the sheath and the
terminal will lead to a decrease in the terminal temperature. Choice of a sufficient length
for the separation may be based on experiment or on a calculation according toIEC/TR 60943.
k) Connection of a short length of conductor, at the termination, whose cross-sectional area
is larger than that required by the current, will reduce the temperature at the termination.
Increasing the cross-sectional area of conductors for other reasons (voltage drop,
withstand of short-circuit currents, reduction of the fault loop impedance) improves the
thermal withstand of the conductors and hence reduces the possibility of excessive
temperatures at terminations.526.4.301 Limitation of the effects of temperature at a terminal in normal service
The effect of temperature rise of terminals can be limited by one or more of the following:
a) Selection of the in...
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