EN 50532:2010

Compact Equipment Assembly for Distribution Substations (CEADS)

This European Standard specifies the service conditions, rated characteristics, general structural requirements and test methods of the prefabricated assembly of the main electrical functional units of a HV/LV Distribution Substation, duly interconnected, for alternating current of rated operating voltages above 1 kV and up to and including 52 kV on the HV side, service frequency 50 Hz. This assembly is to be cable-connected to the network. This Compact Equipment Assembly for Distribution Substation (CEADS) as defined in this standard is designed and tested to be a single product with a single serial number and one set of documentation. Such equipment is delivered as single transport unit. For practical reasons manufacturer and user can agree to transport the unit dismantled if transport or installation of the complete CEADS is not possible. In that case suitable verification tests shall be carried out at the installation site. Note 1: Where the functional units are independent each functional unit will also have its own serial number. A CEADS is not a Distribution Substation, either prefabricated (covered by EN 62271 202) or not (covered by EN 61936-1). However CEADS is intended to become part of a Distribution Substation assembling the HV equipment, the power transformer and the LV equipment duly interconnected (see Annex C, which also explains the origin and types of CEADS). The functions of a CEADS are: – switching and control for the operation of the HV side and protection of the HV/LV transformer functional unit; – HV/LV transformation; – switching and control for the operation and protection of the LV feeders. However relevant provisions of this standard are also applicable to designs where not all of these functions exist (e.g. equipment comprising only HV/LV transformation and switching and control for the operation and protection of the LV feeder functions). For public distribution networks, CEADS are intended for installation within an indoor or outdoor closed electrical operating area (see Definition 1.3.3) forming part of a Distribution Substation. For industrial applications, such as factories, installation of CEADS outside a closed electrical operating area may be allowed provided that safety regulations are fulfilled by additional measures adopted at the installation site under the responsibility of the designer of the installation. This standard considers the potential interaction between the individual functions when closely installed and interconnected to form a type tested assembly and defines ratings, particular design and construction requirements and test procedures for this assembly. NOTE 2 Interaction is the influence of one functional units of the equipment on another (i.e. electrical mechanical and thermal stresses). NOTE 3 For the purpose of this standard a self-protected transformer is considered not as a CEADS, but as a functional unit, designed and type tested to its own product standard EN 60076 13.

Kompakte Gerätekombination für Verteilungsstationen (CEADS)

Diese Europäische Norm beschreibt die Betriebsbedingungen, Bemessungswerte, allgemeine konstruktive Anforderungen und Prüfverfahren für fabrikfertige Gerätekombinationen der bestimmungsgemäß mitein¬ander verbundenen elektrischen Hauptfunktionseinheiten einer Hoch-/Niederspannungs(HS/NS)-Vertei¬lungsstation, für Wechselstrom bei Bemessungs-Betriebsspannungen über 1 kV bis einschließlich 52 kV auf der HS-Seite und für eine Betriebsfrequenz von 50 Hz. Diese Gerätekombination ist mit einer Kabel¬verbindung an das Netz anzuschließen. Die in dieser Norm beschriebene Gerätekombination für Verteilungsstationen (en: Compact Equipment Assembly for Distribution Substation – CEADS) wird als Einzelprodukt geprüft, mit einer Seriennummer versehen und hat eine gemeinsame Dokumentation. Derartige Einrichtungen werden als eine Transport¬einheit geliefert. Jedoch können Hersteller und Anwender vereinbaren, die Transporteinheit zu zerlegen, falls der Transport der kompletten CAEDS nicht durchführbar ist. In diesem Fall müssen geeignete Funktions-prüfungen am Aufstellort durchgeführt werden. ANMERKUNG 1 Wenn die Funktionseinheiten von einander unabhängig sind, hat jede Einheit eine eigene Serien-nummer. Eine CEADS ist keine fabrikfertige (nach EN 62271 202) oder nicht-fabrikfertige (nach EN 61936-1) Verteilungsstation. CEADS sind jedoch dazu vorgesehen, dass sie Teil einer Verteilungsstation werden, in der die HS-Betriebsmittel, der Leistungstransformator und die NS-Betriebsmittel bestimmungsgemäß mitein-ander verbunden sind (siehe Anhang C, in dem auch die Entstehung und die Bauarten von CEADS erläutert werden). Die Funktionen einer CEADS sind: – Schalten und Steuern für den Betrieb der HS-Seite sowie Schutz für die HS/NS-Transformatoreinheit; – HS/NS-Umspannung (Transformator); – Schalten und Steuern für den Betrieb und den Schutz der NS-Abzweige. Wesentliche Bestimmungen dieser Norm gelten jedoch auch für Bauformen, bei denen nicht alle genannten Funktionen vorhanden sind (z. B. Einrichtungen, die nur HS/NS-Umspannen, Schalten oder Steuern und Schützen der NS-Schalteinheit). CEADS sind für Anlagen innerhalb abgeschlossener elektrischer Betriebsstätten (siehe 1.3.3) in Gebäuden oder im Freien vorgesehen, die Teil einer Verteilungsstation sind und hauptsächlich in einem öffentlichen Verteilungsnetz eingesetzt werden. Für industrielle Anwendungen, wie z. B. in Fabriken, ist eine Errichtung von CEADS außerhalb geschlosse¬ner elektrischer Betriebsstätten erlaubt, vorausgesetzt dass Sicherheitsbestimmungen durch zusätzliche Maßnahmen erfüllt werden, die an den Aufstellort angepasst sind; dafür ist der Planer der Anlage verant-wortlich. Die vorliegende Norm berücksichtigt die mögliche Wechselwirkung zwischen den Funktionseinheiten, wenn sie eng nebeneinander aufgebaut und miteinander verbunden sind, um eine typgeprüfte Gerätekombination zu bilden und definiert Bemessungswerte, besondere Konstruktions- und Bauanforderungen sowie Prüf-verfahren für diese Gerätekombination. ANMERKUNG 2 Wechselwirkung ist der Einfluss einer Funktion der Einrichtung auf eine andere (z. B. elektrische, mechanische und thermische Beanspruchung). ANMERKUNG 3 Im Sinne dieser Norm wird ein selbstgeschützter Transformator nicht als CEADS betrachtet, sondern als Funktionseinheit, die nach ihrer eigenen Produktnorm EN 60076 13 konstruiert und typgeprüft ist.

Ensembles Compacts d’Equipement pour Postes de Distribution (ECEPD)

Cette Norme Européenne spécifie les conditions de service, les caractéristiques assignées, les exigences structurelles générales et les méthodes d'essai applicables à l’ensemble préfabriqué d’unités fonctionnelles principales dûment interconnectées d’un Poste de Distribution HT/BT pour courant alternatif de tensions de service assignées supérieures à 1 kV et inférieures ou égales à 52 kV côté HT, de fréquence de service 50 Hz. Cet ensemble est connecté par câbles au réseau. Cet Ensemble Compact d’Equipement pour Postes de Distribution (ECEPD) tel que défini dans cette norme est conçu et testé pour être un produit unique avec un numéro de série unique et un ensemble de documentation. Un tel équipement est livré en une seule unité de transport. Pour des raisons pratiques, le constructeur et l’utilisateur peuvent s’accorder pour transporter l’ensemble démonté si le transport ou l’installation du ECEPD complet n’est pas possible. Dans ce cas des essais de vérification appropriés doivent être réalisés sur le site d’installation. Note 1 Lorsque les unités fonctionnelles sont indépendantes, chaque unité fonctionnelle aura aussi son propre numéro de série. Un ECEPD n’est pas un Poste de Distribution, qu’il soit préfabriqué (couvert par la EN 62271-202) ou non (couvert par la EN 61936-1). Cependant un ECEPD est destiné à devenir une partie d’un Poste de Distribution en regroupant l’équipement HT, le transformateur de puissance et l’équipement BT dûment interconnectés (voir l’Annexe C, qui explique aussi l’origine et les types d’ECEPD). Les fonctions d’un ECEPD sont: - la connexion et la commande pour les opérations côté HT et la protection de l’unité fonctionnelle transformateur HT/BT; - la transformation HT/BT; - la connexion et la commande pour l’exploitation et la protection des départs BT. Cependant les dispositions significatives de cette norme sont aussi applicables à des conceptions pour lesquelles ces fonctions ne sont pas toutes présentes (par exemple équipement comprenant seulement les fonctions transformation HT/BT et connexion et commande pour l’exploitation et la protection des départs BT). Pour les réseaux publics de distribution, les ECEPD sont destinés à être installés dans un local de service électrique fermé, en intérieur ou en extérieur (voir Définition 1.3.3), intégré à un Poste de Distribution. Pour les applications industrielles, comme les usines, l’installation d’un ECEPD en dehors d’un local de service électrique fermé peut être autorisée dans la mesure où les règlements de sécurité sont respectés grâce à l’adoption de dispositions additionnelles sur le site d’installation sous la responsabilité du concepteur de l’installation. Cette norme prend en considération les interactions potentielles entre les unités fonctionnelles lorsqu’elles sont installées à proximité les unes des autres et interconnectées pour former un ensemble d’équipement testé, et définit les caractéristiques assignées, les exigences particulières de conception et de construction et les méthodes d'essai pour cet ensemble d’équipement. NOTE 2 L’interaction est l’influence d’une unité fonctionnelle de l’équipement sur une autre (c.-à-d. contraintes électriques mécaniques et thermiques). NOTE 3 Dans le cadre de la présente norme un transformateur auto-protégé n’est pas considéré comme un ECEPD, mais comme une unité fonctionnelle conçue et testée selon sa propre norme de produit EN 60076 13.

Sestav kompaktne opreme za razdeljevalne (distribucijske) postaje

Ta evropski standard opredeljuje pogoje obratovanja, nazivne značilnosti, splošne strukturne zahteve in metode preskušanja montažnih sestavov glavnih električnih funkcionalnih enot VN/NN(visoke/nizke napetosti) razdeljevalne (distribucijske) postaje, ustrezno povezane, za izmenični tok nazivnih napetosti nad 1 kV ter do vključno 52 kV na VN strani, obratovalna frekvenca 50 Hz. Ta sestav se poveže z omrežjem preko kabla. Ta sestav kompaktne opreme za razdeljevalne postaje, kot je opredeljen v tem standardu, je zasnovan in preskušen kot edini proizvod z enotno serijsko številko ter enim sklopom dokumentacije. Takšna oprema se dobavlja kot ena transportna enota, razen če pogoji transporta in/ali postavitve to otežujejo ali onemogočajo. Sestav kompaktne opreme za razdeljevalne postaje ni razdeljevalna postaja, bodisi montažna (ki je zajeta v EN 62271-202) ali ne (zajeta v EN 61936-1:200X). Vendar pa je sestav kompaktne opreme za razdeljevalne postaje namenjen, da postane del razdeljevalne postaje, ki jo sestavljajo VN oprema, transformator in NN oprema, ustrezno medsebojno povezani (glej Dodatek C), ki tudi pojasnjuje izvor in vrste sestavov kompaktne opreme za razdeljevalne postaje.

General Information

• Status: Withdrawn
• Publication Date: 15-Apr-2010
• Withdrawal Date: 31-Mar-2013
• ICS: 29.130.10 - High voltage switchgear and controlgear
• Technical Committee: CLC/TC 17AC - High-voltage switchgear and controlgear
• Drafting Committee: CLC/TC 17AC - High-voltage switchgear and controlgear
• Parallel Committee: IEC/SC 17C - IEC_SC_17C
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 30-Nov-2019
• Completion Date: 23-Sep-2025
• Ref Project: SIST EN 50532:2010 - Compact Equipment Assembly for Distribution Substations (CEADS)

Relations

• Replaced By: EN 62271-212:2017 - High-voltage switchgear and controlgear - Part 212: Compact Equipment Assembly for Distribution Substation (CEADS)
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2010
Sestav kompaktne opreme za razdeljevalne (distribucijske) postaje
Compact Equipment Assembly for Distribution Substations (CEADS)
Hochspannungs-Schaltgeräte und -Schaltanlagen - Kompakte
Schaltgerätekombinationen für Verteilungsstationen
Ensembles Compacts d’Equipement pour Postes de Distribution (ECEPD)
Ta slovenski standard je istoveten z: EN 50532:2010
ICS:
29.130.10 Visokonapetostne stikalne in High voltage switchgear and
krmilne naprave controlgear
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 50532
NORME EUROPÉENNE
April 2010
EUROPÄISCHE NORM
ICS 29.130.10
English version
Compact Equipment Assembly for Distribution Substations (CEADS)

Ensembles Compacts d’Equipement  Kompakte Gerätekombination
pour Postes de Distribution (ECEPD) für Verteilungsstationen (CEADS)

This European Standard was approved by CENELEC on 2010-04-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50532:2010 E
Foreword
This European Standard was prepared by the Technical Committee CENELEC TC 17AC, High-voltage
switchgear and controlgear. It was submitted to the formal vote and approved by CENELEC on
2010-04-01.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-04-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2013-04-01
__________
– 3 – EN 50532:2010
Contents
Introduction . 6
1 General . 7
1.1 Scope . 7
1.2 Normative references . 8
1.3 Terms and definitions . 9
2 Normal and special service conditions . 10
2.1 Normal service conditions . 10
2.2 Special service conditions . 11
3 Requirements for the individual functional units . 11
4 Ratings . 11
4.1 Rated operating voltages . 12
4.2 Rated insulation levels . 12
4.3 Rated frequenc y . 12
4.4 Rated normal currents . 12
4.5 Rated short-time withstand currents . 12
4.6 Rated peak withstand currents . 12
4.7 Rated durations of short circuit . 12
4.8 Rated supply voltages of closing and opening devices and of auxiliary and control
circuits . 12
4.9 Rated supply frequency of closing and opening devices and of auxiliary circuits . 12
4.10 Rated power of CEADS . 13
5 Design and construction . 13
5.1 Earthing . 13
5.2 Auxiliary equipment . 14
5.3 Nameplate . 14
5.4 Degree of protection and internal fault . 14
5.5 Enclosures . 15
5.6 Sound emission. 16
5.7 Electromagnetic compatibility (EMC) . 16
6 Type test . 16
6.1 General . 16
6.2 Dielectric tests . 17
6.3 Temperature-rise tests . 20
6.4 Measurement of resistance of the main circuit of the HV functional unit . 26
6.5 Short-time and peak withstand current tests on main and earthing circuits . 26
6.6 Functional tests . 27
6.7 Verification of the degree of protection, the resistance to mechanical impacts and
calculation of other mechanical stresses . 27
6.8 Internal arcing tests . 28
6.9 Electromagnetic compatibility tests (EMC) . 28
6.10 Additional tests on auxiliary and control circuits . 29
6.101 Verification of making and breaking capacities . 29
6.102 Mechanical operation tests . 29
6.103 Pressure withstand test for gas-filled compartments . 30
6.104 Measurements of leakage currents of non-metallic enclosures . 30
6.105 Weatherproofing test . 30
6.201 Tightness and mechanical strength for liquid filled compartments . 30
7 Routine tests . 31
7.1 Dielectric tests . 31
7.2 Tests on auxiliary and control circuits . 32
7.3 Measurement of the resistance of the HV main circuit . 32
7.4 Tightness test for the HV functional unit . 32
7.5 Design and visual checks . 32
7.101 Mechanical operation tests on HV functional unit . 32

7.102 Pressure tests of gas-filled compartments . 32
7.103 Tests of auxiliary electrical, pneumatic and hydraulic devices . 32
7.201 Measurement of the resistance of the windings . 33
7.202 Measurement of the voltage ratio . 33
7.203 Measurement of the short circuit impedance and load losses . 33
7.204 Measurement of no-load losses and current . 33
7.301 Inspection of the LV functional unit, including inspection of wiring and, if necessary,
electrical operation test . 33
7.302 Checking of protective measures and of the electrical continuity of the protective circuits
of the LV functional unit . 33
8 Guide to the selection of CEADS for service . 33
8.1 Selection of rated values . 33
8.2 Selection of Internal Arc Classification . 33
8.3 Information . 36
9 Information to be given with enquiries, tenders and orders . 41
9.1 Information with enquiries and orders . 41
9.2 Information with tenders . 42
10 Rules for transport, installation, operation and maintenance . 43
10.1 Conditions during transport, storage and installation. 43
10.2 Installation . 43
10.3 Operation . 44
10.4 Maintenance . 44
10.5 Dismantling, recycling and disposal at the end of service life . 44
11 Safety . 44
11.1 Electrical aspects . 44
11.2 Mechanical aspects . 45
11.3 Thermal aspects. 45
11.4 Internal arc aspects . 45
12 Influence of the product on the environment . 45
Annex A (normative) Method for testing CEADS under conditions of arcing due to an internal
fault . 46
A.1 General . 46
A.2 Internal arc classification . 46
A.3 Selection of tests . 47
A.4 Test arrangements . 48
A.5 Point of initiation of arc . 49
A.6 Current and voltage applied . 50
A.7 Test procedure . 50
A.8 Acceptance criteria . 50
A.9 Test report . 50
A.10 Designation of the internal arc classification . 51
Annex B (normative) Test to verify the sound level of a CEADS . 55
B.1 Purpose . 55
B.2 Test specimen . 55
B.3 Test method . 55
B.4 Measurements . 55
B.5 Presentation and calculation of the results . 55
Annex C (informative) Explanation on CEADS . 56
C.1 Background . 56
C.2 Type of CEADS . 57
C.3 Installation of a HV/LV substation . 58
Bibliography . 63

– 5 – EN 50532:2010
Figures
Figure 1 – Test diagram in case of type tested HV functional unit . 22
Figure 2 – Test diagram in case of non-type tested HV functional unit . 23
Figure 3 – Alternative diagram in case of type tested HV functional unit . 24
Figure 4 – Diagram for the open-circuit test . 24
Figure A.1 – Mounting frame for vertical indicators . 52
Figure A.2 – Horizontal indicators . 52
Figure A.3 – Arrangement of indicators . 53
Figure A.4 – Selection of tests on HV interconnections for class IAC/HV . 54
Figure C.1 – Flow chart from single apparatus to substations (conventional and prefabricated) using
HV enclosed switchgear . 59
Figure C.2 – Equipment assemblies for distribution substations . 60
Figure C.3 – CEADS Type G. 61
Figure C.4 – CEADS Type A . 61
Figure C.5 – CEADS Type I . 62

Tableaux
Table 1 – Locations, causes and examples of measures decreasing the probability of internal arc faults . 35
Table 2 – Examples of measures limiting the consequences of internal arc faults . 36
Table 3 – Summary of technical requirements, ratings for CEADS – Service conditions . 37
Table 4 – Summary of technical requirements, ratings for CEADS – Ratings of the CEADS . 37
Table 5 – Summary of technical requirements, ratings for CEADS – Design and construction of the
CEADS . 40

Introduction
The objective of this standard is to respond to the currently in use compact assemblies that perform the
main electrical functions of a distribution substation. Numerous arrangements are possible and this
standard provides guidance on basic types of assemblies, which might be envisaged (see Annex C).
As there are potential interactions between devices within such assemblies, it is necessary to consider
the standardisation requirements for the assembly in its entirety.

– 7 – EN 50532:2010
1 General
1.1 Scope
This European Standard specifies the service conditions, rated characteristics, general structural
requirements and test methods of the prefabricated assembly of the main electrical functional units of a
HV/LV Distribution Substation, duly interconnected, for alternating current of rated operating voltages
above 1 kV and up to and including 52 kV on the HV side, service frequency 50 Hz. This assembly is to
be cable-connected to the network.
This Compact Equipment Assembly for Distribution Substation (CEADS) as defined in this standard is
designed and tested to be a single product with a single serial number and one set of documentation.
Such equipment is delivered as single transport unit. For practical reasons manufacturer and user can
agree to transport the unit dismantled if transport or installation of the complete CEADS is not possible. In
that case suitable verification tests shall be carried out at the installation site.
Note 1: Where the functional units are independent each functional unit will also have its own serial number.
A CEADS is not a Distribution Substation, either prefabricated (covered by EN 62271-202) or not
(covered by EN 61936-1). However CEADS is intended to become part of a Distribution Substation
assembling the HV equipment, the power transformer and the LV equipment duly interconnected (see
Annex C, which also explains the origin and types of CEADS).
The functions of a CEADS are:
– switching and control for the operation of the HV side and protection of the HV/LV transformer
functional unit;
– HV/LV transformation;
– switching and control for the operation and protection of the LV feeders.
However relevant provisions of this standard are also applicable to designs where not all of these
functions exist (e.g. equipment comprising only HV/LV transformation and switching and control for the
operation and protection of the LV feeder functions).
For public distribution networks, CEADS are intended for installation within an indoor or outdoor closed
electrical operating area (see Definition 1.3.3) forming part of a Distribution Substation.
For industrial applications, such as factories, installation of CEADS outside a closed electrical operating
area may be allowed provided that safety regulations are fulfilled by additional measures adopted at the
installation site under the responsibility of the designer of the installation.
This standard considers the potential interaction between the individual functions when closely installed
and interconnected to form a type tested assembly and defines ratings, particular design and construction
requirements and test procedures for this assembly.
NOTE 2 Interaction is the influence of one functional units of the equipment on another (i.e. electrical mechanical and thermal
stresses).
NOTE 3 For the purpose of this standard a self-protected transformer is considered not as a CEADS, but as a functional unit,
designed and type tested to its own product standard EN 60076-13.

1.2 Normative references
The following referenced documents are indispensable for the application 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.
EN 50464 series, Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 2 500 kVA
with highest voltage for equipment not exceeding 36 kV
EN 50464-1:2007, Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 2 500 kVA
with highest voltage for equipment not exceeding 36 kV – Part 1: General requirements
EN 50464-4:2007, Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 2 500 kVA
with highest voltage for equipment not exceeding 36 kV – Part 4: Requirements and tests concerning
pressurised corrugated tanks
EN 60076 series, Power transformers (IEC 60076 series)
EN 60076-1:1997 + A11:1997 + A1:2000 + A12:2002, Power transformers – Part 1: General
(IEC 60076-1:1993, mod. + A1:1999)
EN 60076-2:1997, Power transformers – Part 2: Temperature rise (IEC 60076-2:1993, mod.)
EN 60076-3:2001, Power transformers – Part 3: Insulation levels, dielectric tests and external clearances
in air (IEC 60076-5:2000 + corr. Dec. 2000)
EN 60076-5: 2006, Power transformers – Part 5: Ability to withstand short circuit (IEC 60076-5: 2006)
EN 60076-10, Power transformers – Part 10: Determination of sound levels (IEC 60076-10)
EN 60076-11:2004, Power transformers – Part 11: Dry-type transformers (IEC 60076-11:2004)
EN 60076-13:2007, Power transformers - Part 13: Self-protected liquid-filled transformers (IEC 60076-
13:2006)
EN 60243-1, Electrical strength of insulating materials – Test methods – Part 1: Tests at power
frequencies (IEC 60243-1)
EN 60439 series, Low-voltage switchgear and controlgear assemblies (IEC 60439 series)
EN 60439-1:1999, Low-voltage switchgear and controlgear assemblies – Part 1: Type-tested and partially
type-tested assemblies (IEC 60439-1:1999)
EN 60529, Degrees of protection provided by enclosures (IP Code) (IEC 60529:1989)
EN 60664-1:2003, Insulation coordination for equipment within low-voltage systems – Part 1: Principles,
requirements and tests (IEC 60664-1:1992 + A1:2000 + A2:2002)
EN 60721-1, Classification of environmental conditions – Part 1: Environmental parameters and their
severities (IEC 60721-1)
EN 60947-1, Low-voltage switchgear and controlgear – Part 1: General rules (IEC 60947-1)
1)
EN 61439 series , Low-voltage switchgear and controlgear assemblies (IEC 61439 series)
2)
EN 61936-1, Power installations exceeding 1 kV a.c. – Part 1: Common rules (IEC 61936-1 )
EN 62262, Degrees of protection provided by enclosures for electrical equipment against external
mechanical impacts (IK code) (IEC 62262)
———————
1)
This series will supersede some parts of EN 60439 series.

– 9 – EN 50532:2010
EN 62271-1:2008, High-voltage switchgear and controlgear – Part 1: Common specifications
(IEC 62271-1:2007)
EN 62271-200:2004, High-voltage switchgear and controlgear – Part 200: AC metal-enclosed switchgear
and controlgear for rated voltages above 1 kV and up to and including 52 kV (IEC 62271-200:2003)
EN 62271-201:2006, High-voltage switchgear and controlgear – Part 201: AC insulation-enclosed
switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV
(IEC 62271-201:2006)
EN 62271-202, High-voltage switchgear and controlgear – Part 202: High voltage/low voltage
prefabricated substation (IEC 62271-202)
HD 60364-4-41, Low-voltage electrical installations – Part 4-41: Protection for safety – Protection against
electric shock (IEC 60364-4-41)
IEC 60050-441, International Electrotechnical Vocabulary – Switchgear, controlgear and fuses
IEC 60721-2-2, Classification of environmental conditions – Part 2: Environmental conditions appearing in
nature. Precipitation and wind
IEC 60721-2-4, Classification of environmental conditions – Part 2-4: Environmental conditions appearing
in nature – Solar radiation and temperature
IEC/TS 60815 series, Selection and dimensioning of high-voltage insulators intended for use in polluted
conditions
IEC/TR 62271-300, High-voltage switchgear and controlgear – Part 300: Seismic qualification of
alternating current circuit-breakers
1.3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-441, EN 62271-1:2008
and in the standards mentioned in 1.2, and the following apply.
1.3.1
Compact Equipment Assembly for Distribution Substation (CEADS)
prefabricated and type-tested assembly comprising functional units, described in 1.1, duly interconnected
(see Annex C for details)
1.3.1.1
grouped type CEADS (CEADS-G)
CEADS which functional units are stand alone equipment fully complying with their respective product
standards. These equipment is placed close to each other in a specified layout
1.3.1.2
associated type CEADS (CEADS-A)
CEADS which functional units may deviate from existing product standard but not in any aspect that could
affect negatively safety and/or operation. They can either be independent units or share part of their
frames or enclosures
1.3.1.3
integrated type CEADS (CEADS-I)
CEADS where all or part of HV functional units and the HV/LV transformation functional unit are
contained in a single enclosure, sharing the insulating medium

1.3.2
functional unit
assembly of devices and components performing a given main function of the CEADS
NOTE For the purpose of this standard functional unit has a different meaning than the meaning in other standards. For example
in this standard HV functional unit (see the definition below) may comprise several functional units as per EN 62271-200:2004.
1.3.2.1
HV functional unit
assembly of the switching devices and other components performing the function of switching and control
for the operation of the HV side of the CEADS. It may include switching and control of the HV main ring of
the network and the protection of the HV/LV transformation function
1.3.2.2
HV/LV transformer functional unit
assembly of elements that perform the function of HV/LV transformation of the CEADS
1.3.2.3
LV functional unit
assembly of the switching devices and other components performing the function of switching and control
for the operation and protection of the LV feeders of the CEADS
1.3.3
closed electrical operating area
room or location for operation of electrical installations and equipment to which access is intended to be
restricted to skilled or instructed persons or to lay personnel under the supervision of skilled or instructed
persons, e.g. by opening of a door or removal of protective barrier only by the use of a key or tool, and
which is clearly marked by appropriate warning sign (see 3.2.1 of EN 61936-1)
1.3.4
internal arc classified CEADS (IAC/HV)
CEADS which meet prescribed criteria, demonstrated by type tests, for the protection of persons in the
event of internal arc at the HV side
2 Normal and special service conditions
Clause 2 of EN 62271-1:2008 is applicable with the following addition:
2.1 Normal service conditions
Wave shape and symmetry of supply voltage will be in accordance with 1.2.1 of EN 60076-1:1997.
For HV/LV transformer functional unit, average ambient air temperature limits of 4.3.1 of
EN 60076-2:1997 for oil immersed type and 4.2.3 of EN 60076-11:2004 shall also apply.
For indoor CEADS
– the minimum air ambient temperature is -5 °C or -15 °C;
– equipment shall also be suitable for conditions of humidity in accordance with clause 6.1.2.1 of EN
60439-1:1999.
For outdoor CEADS
– the preferred values of minimum air ambient temperature are -10 °C, -25 °C.
NOTE For air ambient below -25 °C, CEADS shall be designed or used according to the relevant product standards, where
applicable, or according to agreement between manufacturer and user.

– 11 – EN 50532:2010
2.2 Special service conditions
Refer to the relevant standards for the different functional units.
3 Requirements for the individual functional units
The complete assembly of a CEADS and the individual functional units forming part of it shall comply with
the requirements of this standard. For the individual functional units reference is made to the following
respective standards:
– HV functional unit . EN 62271-200:2004 or EN 62271-201:2006;
– HV/LV transformer functional unit . EN 60076 series;
– LV functional unit . EN 60439 series.
In a CEADS-G the individual functional units shall comply with the requirements of their respective
product standard listed above.
Concerning CEADS-A and CEADS-I, the individual functional units may deviate in some aspects from
those products standards. Due to that, specific testing procedures for individual functional units, where
direct application of above mentioned product standards is not possible, are described in this standard.
4 Ratings
The ratings of a CEADS comprise the following:
a) rated operating high voltage;
b) rated operating low voltage;
c) rated insulation level for high voltage;
d) rated insulation level for low voltage;
e) rated frequency;
f) rated normal current on high voltage side;
g) rated normal current of low voltage circuits;
h) rated short-time withstand current, peak withstand current and duration of short circuit for main HV
circuit;
i) rated short-time withstand current, peak withstand current and duration of short circuit for main LV
circuit;
j) rated short-time withstand current , peak withstand current and duration of short circuit for main
earthing circuit;
k) rated power and total losses;
l) rated supply voltage of closing and opening devices and auxiliary and control circuits (if any);
m) rated supply frequency of closing and opening devices and auxiliary and control circuits (if any).
The ratings of CEADS shall be assigned to ensure that operation of the equipment within its assigned
ratings does not expose any individual functional unit to conditions which are outside its rated capabilities.

NOTE Functional units forming part of the CEADS may have other individual rated values in accordance with their relevant
standards.
4.1 Rated operating voltages
Subclause 3.4.3 of EN 60076-1:1997 is applicable.
NOTE These values are determined by the characteristics of the HV/LV transformer functional unit. HV and LV functional units can
have higher rated voltages.
4.2 Rated insulation levels
Table 2 of 7.2 of EN 60076-3:2001 is applicable.
NOTE These values are determined by the characteristics of the HV/LV transformer functional unit. HV and LV functional units can
have higher rated insulating levels.
4.3 Rated frequency
The rated frequency of CEADS is 50 Hz.
4.4 Rated normal currents
Subclauses 4.4.1 of EN 62271-1:2008 for HV functional unit and 4.2 of EN 60439-1:1999 for LV
functional unit are applicable.
4.5 Rated short-time withstand currents
Subclauses 4.5 of EN 62271-1:2008 for HV functional unit and 4.3 of EN 60439-1:1999 for LV functional
unit are applicable.
The rated short-time withstand current assigned to the earthing circuit may differ from that of the main
circuit.
4.6 Rated peak withstand currents
Subclauses 4.6 of EN 62271-1:2008 for HV functional unit and 4.4 of EN 60439-1:1999 for LV functional
unit are applicable.
The rated peak withstand current assigned to the earthing circuit may differ from that of the main circuit.
4.7 Rated durations of short circuit
Subclauses 4.7 of EN 62271-1:2008 for HV functional unit, 4.1.3 of EN 60076-5:2006 for the HV/LV
transformer functional unit and 4.3 of EN 60439-1:1999 for LV functional unit are applicable.
The rated duration of short circuit assigned to the earthing circuit may differ from that of the main circuit.
4.8 Rated supply voltages of closing and opening devices and of auxiliary and control
circuits
Subclauses 4.8 of EN 62271-1:2008 for HV functional unit and 4.1.1 of EN 60439-1:1999 for LV
functional unit are applicable.
4.9 Rated supply frequency of closing and opening devices and of auxiliary circuits
Subclauses 4.9 of EN 62271-1:2008 for HV functional unit and 4.8 of EN 60439-1:1999 for LV functional
unit are applicable.
– 13 – EN 50532:2010
4.10 Rated power of CEADS
The rated power of CEADS is given by the rated power and the total losses of the HV/LV transformer
functional unit at rated operating voltages and rated normal currents for which the CEADS has been
designed.
5 Design and construction
CEADS shall be designed so that normal service, inspection and maintenance can be carried out safely.
As CEADS are intended for installation within closed electrical operating areas, in principle general public
is not allowed to approach the equipment. However when a CEADS is installed in a factory the workers
not in charge of the operation of the equipment may be occasionally in the proximity of the CEADS. As
they are not aware of the electrical features of the equipment they are considered as public in the sense
of this standard.
NOTE If some parts of enclosures of a CEADS are intended to become part of the enclosure of a substation the relevant
requirements of EN 62271-202 or EN 61936-1, as applicable, shall be met.
The design of CEADS shall take into account the possible interactions (e.g. electrical, mechanical and
thermal) in the performance of different functional units and the components used to interconnect these.
The design and construction of the individual functional units of CEADS-G shall comply with the
requirements of their respective product standards as specified in clause 3. For CEADS-A and CEADS-I
the individual product standards shall apply except where direct application is not possible.
5.1 Earthing
A main earthing conductor system shall be provided to connect to the earth all metallic parts of the
CEADS not belonging to the main and/or secondary/auxiliary circuits of the equipment. It consists of a
main earthing conductor to which each component is connected through a single circuit.
If the CEADS has a metallic frame, then it may serve as, or form part of, the main earthing conductor. The
fastening system, if any, used to join parts of the frame shall demonstrate to pass the current carrying
capability test. The main earthing conductor system shall be designed to withstand the rated short-time
and peak withstand current under the neutral earthing condition of the system.
The cross-section of the earthing conductor shall be not less than 30 mm². It shall be terminated by an
adequate terminal intended for connection to the earth system of the installation. If the earthing conductor
is not made of copper, equivalent thermal and mechanical requirements shall be met.
The continuity of the earth system shall be ensured and corresponding measures preventing corrosion,
loosening of bolts etc. shall be taken, taking into account the thermal and mechanical stresses caused by
the current it may have to carry.
NOTE The users may establish procedures to check the integrity of all parts of the earthing system (internal and external) either
periodically or after a short-circuit current has flown into the earthing system.
Components to be connected to the main earthing conductor system shall include
– the enclosure, if metallic, of the HV functional units from the terminal provided for that purpose;
– the tank of liquid filled HV/LV transformer functional unit or the metallic non active parts of dry-type
HV/LV transformer functional unit;
– the frame and/or enclosure, if metallic, of the LV functional unit;
– the earthing connection of automatic controls and remote-control devices;
– the metal shields and the earthing conductors of the HV cables;

– the metallic frame of the CEADS, if any;
– earthing switches, if any.
5.2 Auxiliary equipment
For the low-voltage installation embedded in the CEADS (for example, illumination, auxiliary supply, etc.),
refer to HD 60364-4-41 or EN 60439-1:1999, as appropriate.
5.3 Nameplate
Each CEADS shall be provided with a durable, clearly legible nameplate, visible in normal service
condition, which shall contain at least the following information:
– manufacturer’s name or trade mark;
– type designation;
– serial number;
– number of this standard;
– year of manufacture;
– ratings of CEADS listed in Clause 4;
– internal arc designation, where applicable.
The ratings of the functional units shall be listed on separate nameplates, clearly visible, or on the
CEADS nameplate. Where functional units are independent they shall be provided with separate
nameplates. Each nameplate shall have a unique serial number.
5.4 Degree of protection and internal fault
5.4.1 Degree of protection
Degrees of protection in accordance with EN 60529 shall be as specified below.
The enclosures of HV and LV functional units shall provide at least the degree of protection IP2X for
indoor application.
For outdoor application the minimum degree of protection shall be IP23.
If non insulated conductors and/or bushings in LV interconnections or non screened conductors and/or
bushings in HV interconnections are used, suitable means to prevent direct contact with live parts shall be
provided either by the manufacturer as part of the CEADS itself or alternatively by the user incorporating
adequate protection in the installation site. In the first case the minimum degree of protection should be
IP1X. In the second case the manufacturer shall include in the instruction manual clear information about
the need to provide additional protection.
When dry type transformer is used, a protection means around the transformer shall be provided with at
least a degree of protection IP1X.
5.4.2 Protection against mechanical stresses
The enclosures of HV and LV functional units shall withstand external mechanical impacts with energy of
2 J, corresponding to a degree of protection IK07 for indoor application and 20 J corresponding to IK10
for outdoor application.
– 15 – EN 50532:2010
CEADS intended for outdoor use shall withstand the following additional loads:
– snow loads according to the local climatic conditions;
– wind loads according to 2.1.2 of EN 62271-1:2008.
5.4.3 Protection of the environment due to internal defects
In the event that internal defects may lead to the escape of hazardous liquids from the equipment (for
example: oil from a transformer or switchgear), provision shall be made to retain the hazardous liquids in
order to prevent the soil being polluted.
The capacity of the retention tank shall be at least equal to the biggest hazardous liquid containing part
(for example, transformer, switchgear, etc), unless applicable national regulations have different
requirements.
Additional measures may be taken by agreement between manufacturer and user. Those provisions may
be a part of the
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