prEN IEC 61439-8:2025

SLOVENSKI STANDARD
01-junij-2025
Sestavi nizkonapetostnih stikalnih in krmilnih naprav - 8. del: Sestavi za uporabo v
fotonapetostnih inštalacijah
Low-voltage switchgear and controlgear assemblies - Part 8: Assemblies for use in
photovoltaic installations
Niederspannungs-Schaltgerätekombinationen – Teil 8: Schaltgerätekombinationen für
den Einsatz in Photovoltaik-Anlagen
Ensembles d'appareillage à basse tension - Partie 8: Ensembles destinés aux
installations photovoltaïques
Ta slovenski standard je istoveten z: prEN IEC 61439-8:2025
ICS:
27.160 Sončna energija Solar energy engineering
29.130.20 Nizkonapetostne stikalne in Low voltage switchgear and
krmilne naprave controlgear
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

121B/213/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61439-8 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2025-04-18 2025-06-13
SUPERSEDES DOCUMENTS:
121B/199/CDV, 121B/211/RVC
IEC SC 121B : LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR ASSEMBLIES
SECRETARIAT: SECRETARY:
Germany Mr Jörg Hußmann
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):
TC 23, SC 23E, TC 64, TC 82, SC 121A
ASPECTS CONCERNED:
Electromagnetic Compatibility, 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.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which 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” clau ses to be
included should this proposal proceed. Recipients are reminded that the CDV stage is the final stage for submitting ISC c lauses. (SEE
AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Low-voltage switchgear and controlgear assemblies – Part 8: Assemblies for use in photovoltaic installations

PROPOSED STABILITY DATE: 2028
NOTE FROM TC/SC OFFICERS:
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.

121B/213/CDV – 2 – IEC CDV 61439-8 © IEC 2025
CONTENTS
FOREWORD . 5
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 11
3.1 General terms . 11
3.2Constructional units of assemblies . 12
3.2 Constructional units of PVAs . 12
3.4 Structural parts of assemblies . 12
3.4 Structural parts of PVA . 12
3.5 Conditions of installation of PVA . 13
3.5.101 PVA location with restricted access . 13
3.5.102 PVA location with non-restricted access . 13
3.5.103 base . 13
3.5.104 fixing mean . 13
3.103 Electrical connections of functional units . 13
4 Symbols and abbreviations . 14
5 Interface characteristics . 14
5.1 General . 14
5.2 Voltage ratings . 14
5.2.2 Rated operational voltage (U ) (of a circuit of a PVA) . 14
e
5.3 Current ratings . 14
5.3.1 Rated current of the assembly (I ) . 14
nA
5.3.2 Group rated current of an incoming circuit (I ) . 14
ng
5.3.3 Maximum short-circuit current (I ) . 15
SC MAX
5.6 Other characteristics . 15
6 Information . 15
6.1Assembly designation marking . 15
6.1 PVA designation marking . 15
6.2 Documentation . 16
6.2.2 Instructions for handling, installation, operation and maintenance . 16
7 Service conditions . 16
7.101 PVA under solar radiation conditions . 16
7.2 Special service conditions . 16
8 Constructional requirements . 16
8.2 Degree of protection provided by an assembly enclosure . 16
8.2.1 Mechanical strength of PVA for PVA enclosure . 17
8.2.2 Protection against contact with live parts, ingress of solid foreign bodies
and water (IP code) . 17
8.2.101 PVA with withdrawable parts. 17
8.3 Clearances and creepage distances. 18
8.3.2 Clearances . 18
8.4 Protection against electric shock . 18
8.4.1 General . 18
8.4.3 Fault protection . 18

IEC CDV 61439-8 © IEC 2025 – 3 – 121B/213/CDV
8.4.3.2.2 Requirements for earth continuity providing protection against the
consequences of faults within the Class I assembly . 18
8.4.5 Limitation of steady-state touch currents and charge . 18
8.4.6 Operating and servicing condition . 18
8.5 Incorporation of switching devices and components . 19
8.5.2 Removable parts . 19
8.5.2 Removable and withdrawable parts . 19
8.5.3 Selection of switching devices and components . 19
8.5.4 Installation of switching devices and components . 20
8.101 Internal separation of PVA . 20
8.102 Thermal cycling durability . 21
8.103 Climatic durability . 21
9 Performance requirements . 21
9.1 Dielectric properties . 21
9.1.3 Impulse withstand voltage . 21
9.2 Temperature-rise limits . 21
9.2.1 General . 21
9.3 Short-circuit protection and short-circuit withstand strength . 21
9.3.1 General . 21
10 Design verification . 22
10.1 General . 22
10.2 Strength of materials and parts . 22
10.2.2 Resistance to ultraviolet (UV) radiation . 22
10.2.6 Verification of protection against mechanical impact (IK code) . 22
10.2.701 Verification of mechanical strength for PVA . 22
10.2.8 Mechanical operation . 30
10.3 Degree of protection of PVA (IP Code) . 30
10.9 Dielectric properties . 31
10.9.3 Impulse withstand voltage . 31
10.10 Temperature-rise . 31
10.10.1 General . 31
10.10.2 Verification by testing . 31
10.10.4 Verification assessment . 33
10.11 Short-circuit withstand strength . 35
10.11.5 Verification by test . 35
10.101 Thermal cycling test . 35
10.102 Climatic test . 36
11 Routine verification . 36
11.8 Mechanical operation . 36
Annexes . 42
Annex AA (informative) Items subject to agreement between the assembly
manufacturer and the user . 43
Annex BB (informative) Forms of internal separation (see 8.101) . 47
Annex CC (informative) Determining power loss by measurement for circuits
exceeding 1 600 A in a reference design . 52
CC.1General . 52
CC.2Method of measurement. 52
CC.2.1Power loss measurement for AC circuits . 52

121B/213/CDV – 4 – IEC CDV 61439-8 © IEC 2025
CC.2.2Power loss measurement for DC circuits . 52
Annex DD (informative) Design verification (PVA only) . 54
Annex EE (informative) List of notes concerning certain countries . 56
Annex FF (informative) Examples of PV installations . 57
FF.1 Examples of PV installation .
...