IEC TR 61439-0:2013

IEC/TR 61439-0 ®
Edition 2.0 2013-04
TECHNICAL
REPORT
Low-voltage switchgear and controlgear assemblies –
Part 0: Guidance to specifying assemblies

IEC/TR 61439-0:2013(E)
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IEC/TR 61439-0 ®
Edition 2.0 2013-04
TECHNICAL
REPORT
Low-voltage switchgear and controlgear assemblies –

Part 0: Guidance to specifying assemblies

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 29.130.20 ISBN 978-2-83220-787-1

– 2 – TR 61439-0 © IEC:2013(E)
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
4 Application of ASSEMBLIES within the IEC 61439 series . 10
4.1 General . 10
4.2 ASSEMBLY design and verification . 10
4.3 Service conditions and interface characteristics . 10
4.4 Design . 11
5 Electrical system . 11
5.1 General . 11
5.2 Earthing system . 11
5.3 Nominal voltage . 11
5.4 Transient overvoltages . 12
5.5 Unusual voltage transients, temporary overvoltages . 13
5.6 Rated frequency f (Hz) . 13
n
5.7 Additional on-site testing requirements: wiring, operational performance and
function . 14
6 Short-circuit withstand capability . 14
6.1 General . 14
6.2 Prospective short-circuit current at supply terminals I (kA) . 14
cp
6.3 Prospective short-circuit current in the neutral . 15
6.4 Prospective short-circuit current in the protective circuit . 15
6.5 Short-circuit protective device (SCPD). 15
6.6 Co-ordination of short-circuit protective devices including external short-
circuit protective device details . 16
6.7 Data associated with loads likely to contribute to the short-circuit current . 16
7 Protection of persons against electric shock . 17
7.1 General . 17
7.2 Basic protection (protection against direct contact) . 17
7.2.1 General . 17
7.2.2 Basic insulation provided by insulating material . 17
7.2.3 Barriers or enclosures . 17
7.3 Fault protection (protection against indirect contact) . 18
7.3.1 General . 18
7.3.2 Requirements for the protective conductor to facilitate automatic
disconnection of the supply . 18
7.3.3 Electrical separation . 19
7.3.4 Protection by total insulation . 19
8 Installation environment . 20
8.1 General . 20
8.2 Location type . 20
8.3 Protection against ingress of solid foreign bodies and ingress of water . 20
8.4 External mechanical impact . 21
8.5 Resistance to UV radiation . 21
8.6 Resistance to corrosion . 21

TR 61439-0 © IEC:2013(E) – 3 –
8.7 Ambient air temperature . 21
8.8 Maximum relative humidity . 21
8.9 Pollution degree . 22
8.10 Altitude . 22
8.11 EMC environment . 22
8.12 Special service conditions . 23
8.12.1 General . 23
8.12.2 Climatic conditions . 24
8.12.3 Protection against ingress of solid foreign bodies and ingress of
water . 24
8.12.4 Shock, vibration, seismic occurrence and external mechanical impact
(IK) . 24
8.12.5 Fire and explosion hazards . 24
8.12.6 Exceptional overvoltages . 25
8.12.7 EMC environment . 25
9 Installation method . 25
9.1 General . 25
9.2 Assembly type . 25
9.3 Portability . 26
9.4 Maximum overall dimensions and weight . 26
9.5 External conductor type(s) . 26
9.6 Direction(s) of external conductors . 26
9.7 External conductor material . 26
9.8 External phase conductor, cross-sections, and terminations . 27
9.9 External PE, N, PEN conductors cross-sections, and terminations . 27
9.10 Special terminal identification requirements . 27
10 Storage and handling . 28
10.1 General . 28
10.2 Maximum dimensions and weight of transport units . 28
10.3 Methods of transport (e.g. forklift, crane) . 28
10.4 Environmental conditions different from the service conditions . 28
10.5 Packing details . 28
11 Operating arrangements . 28
11.1 General . 28
11.2 Access to manually operated devices . 29
11.3 Isolation of load installation equipment items . 29
12 Maintenance and upgrade capabilities . 30
12.1 General . 30
12.2 Requirements related to accessibility for inspection and similar operations . 30
12.3 Requirements related to accessibility for maintenance in service by
authorized persons . 30
12.4 Requirements related to extension under voltage . 31
12.5 Protection against direct contact with hazardous live internal parts during
maintenance or upgrade . 31
12.6 Method of functional units connection . 31
12.7 Operating and maintenance gangways within an ASSEMBLY . 32
12.8 Internal separation . 32
13 Current carrying capability . 32
13.1 General . 32

– 4 – TR 61439-0 © IEC:2013(E)
13.2 Rated current I (A) (maximum current allowable) . 32
nA
13.3 Rated current of circuits I (A) . 33
nc
13.4 Rated diversity factor (RDF) . 33
13.5 Ratio of cross-section of the neutral conductor to phase conductors . 33
13.5.1 General .
...