SIST EN 50124-1:2002/A1:2004

SLOVENSKI SIST EN 50124-1:2002/A1:2004

STANDARD
september 2004
Železniške naprave – Uskladitev izolacije – 1. del: Osnovne zahteve –
Izolacijske in plazilne razdalje za vso električno in elektronsko opremo –
Dopolnilo A1
Railway applications - Insulation coordination - Part 1: Basic requirements;
Clearances and creepage distances for all electrical and electronic equipment -
Amendment A1
ICS 29.080.01; 29.280 Referenčna številka
SIST EN 50124-1:2002/A1:2004(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

---------------------- Page: 1 ----------------------

EUROPEAN STANDARD EN 50124-1/A1
NORME EUROPÉENNE
EUROPÄISCHE NORM October 2003

ICS 29.080.00; 45.020


English version


Railway applications -
Insulation coordination
Part 1: Basic requirements -
Clearances and creepage distances
for all electrical and electronic equipment


Applications ferroviaires -  Bahnanwendungen -
Coordination de l'isolement Isolationskoordination
Partie 1: Prescriptions fondamentales - Teil 1: Grundlegende Anforderungen -
Distances d'isolement dans l'air et Luft- und Kriechstrecken für alle
lignes de fuite pour tout matériel elektrischen und elektronischen
électrique et électronique Betriebsmittel





This amendment A1 modifies the European Standard EN 50124-1:2001; it was approved by CENELEC
on 2003-10-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this amendment 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 amendment 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, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.

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

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 50124-1:2001/A1:2003 E

---------------------- Page: 2 ----------------------

EN 50124-1:2001/A1:2003 – 2 –
Foreword
This amendment to the European Standard EN 50124-1:2001 was prepared by the Technical
Committee CENELEC TC 9X, Electrical and electronic applications for railways.
The text of the draft was submitted to the formal vote and was approved by CENELEC as
amendment A1 to EN 50124-1:2001 on 2003-10-01.
The following dates were fixed:
- latest date by which the amendment has to be implemented
 at national level by publication of an identical
 national standard or by endorsement (dop) 2004-10-01
- latest date by which the national standards conflicting
 with the amendment have to be withdrawn (dow) 2006-10-01
Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.
In this standard, Annexes A, B, C and D are normative and Annexes E, F and G are informative.
__________
Annex F (informative) Bibliography
Add the following documents:
EN 50123 series Railway applications - Fixed installations - D.C. switchgear
EN 50152 series Railway applications - Fixed installations - Particular requirements for a.c.
switchgear
EN 50153 Railway applications - Rolling stock - Protective provisions relating to
electrical hazards
EN 61558 series Safety of power transformers, power supply units and similar devices

---------------------- Page: 3 ----------------------

– 3 – EN 50124-1:2001/A1:2003
Add the following annex:
Annex G
(informative)

Application guide
G.1 Introduction
The term "insulation co-ordination" explains the process for co-ordinating the constituents of an
electrical insulation, i.e. solid/liquid insulation, clearances and creepage distances.
NOTE The dimensioning of insulation thicknesses performed by solid insulation and insulation distances performed by liquid insulation
materials is not covered by this standard.
However, the use of this standard for the determination of clearances and creepages needs some
additional explanations: The values of the tables of Annex A are based on EN 60664-1 and
EN 60071-1 taking into account the severe electrical and mechanical situation of insulations in
railway systems and their expected reliability and long life time.
For example, the values for clearances are selected for inhomogeneous fields and, for locations
with typical railway pollutions are supplemented by safety margins. Thus, it is not necessary to
perform a high voltage test, when clearances required by this standard are achieved.
Where product standards for railway applications specify test voltages and clearances, the use of
these values is recommended. According to 1.1 it can be assumed that the insulation values in the
product standards were derived in accordance with this European Standard.
G.2 Determination of minimum clearances and creepage distances
G.2.1 Sections
For practical use when determining insulation values it is necessary to consider the following
factors when dividing into sections:
– is the considered part of the circuit exposed to the same electrical climate? (working voltage,
overvoltage category);
– are the location criteria of the regarded part of circuit the same? (pollution degree,
indoors/outdoors);
– for economical reasons it may be useful to subdivide sections (e.g. for lower insulation values
in areas with lower voltage stress);
– for reliability or safety reasons it may be useful to increase insulation values in endangered
areas, i.e. by introducing a separate section.
For floating sections consideration should be given to capacitive effects for defining the
dimensioning parameters of an insulation. Due to the actual or parasitic capacitances between the
regarded section and adjacent sections, creepage and clearances can be stressed by continuous
voltages greater than the nominal voltage of the circuit. The correct selection of U and U should
Nm Ni
take that effect into account.

---------------------- Page: 4 ----------------------

EN 50124-1:2001/A1:2003 – 4 –
G.2.2 Use of method 1 and 2 for determining U
Ni
Methods 1 and 2 are considered as equivalent for dimensioning clearances because both methods
lead to reliable distances.
Method 2 is a physical method to determine an insulation value taking into account the voltage
stress occurring across the regarded insulation but it can only be used if the expected overvoltages
are well known.
If the overvoltages are not known, method 1 should be used.
G.2.3 How to determine minimum clearances and creepage distances
The flowchart of Figure G.1 displays the procedure for determining the minimum clearances and
creepage distances by taking into account the relevant electrical, environmental and operating
conditions.

---------------------- Page: 5 ----------------------

– 5 – EN 50124-1:2001/A1:2003
Step 1 3
Division of the electrical circuit into
2
sections which are to be handled separately.
For all points of this section
Sections 1,2,3.
the same voltage stress applies
The complete circuit or only a single point
For each section
of the circuit may be defined as a section
the following steps are to be
performed
Step 2
Determination of rated insulation voltage The section is powered direct by a
for the section of the circuit  standardised railway voltage U
n
U
Nm
yes no
Fixed installations:
Manufacturer’s determination
Rolling stock:
Manufacturer’s determination
determination according
according to 1.3.2.4 and Table A.1
Table D.1
according to 1.3.2.4 and table A.1
to 2.2.1
Rated insulation voltage
for the section of the circuit
U
Nm
Step 3 Selection of insulation type The section includes live parts.
The insulation provides a basic protection
According to 1.3.4 for the section
Product standards may state a preselection against electric shock
Insulation between conductive parts
In case of insulation failure,
only for proper functioning
the danger of an electric shock is given
no yes yes
Basic-
Functional Basic insulation
insulation insulation
+
Supplementary
insulation
(may be solid Insulation)
=
Reinforced insulation
Double insulation
(as a single insulation
Basic + Suppl.
system)
Step 4
Pollution degree
Choice of pollution degree Signalling
PD1.PD4A
6.1
for the section of the circuit
Table A.4 + Annex E
Pollution degree
Rolling stock
PD1.PD4
6.2
Pollution degree
Fixed installation
PD1.PD4B
6.3

Figure G.1 – Determination of minimum clearances and creepage distances

---------------------- Page: 6 ----------------------

EN 50124-1:2001/A1:2003 – 6 –
Step 5
rated impulse voltage All overvoltages
Determination of
are known by calculation
for this section of circuit
yes
yes / no
U or by measurement
Ni
and the minimum clearance in air
Method 1 Method 2 (2.2.2.2)
According to 2.2.2.1 Calculation or measurement
of this standard of working peak voltages
Determination of
Overvoltage categorie Calculation or measurement of
OV1.OV4 all working peak voltages
2.2.2.1 in this section (including transients
and clause 6 and induced voltages)
and Clause 6
The maximum of this peak
voltages is
U from Step 2
Nm
Table A.1
Table A.2
Rated impulse voltage for the section
UNi
PD from Step 4
Table A.3
Interpolation permitted
Minimum clearance for basic insulation
Minimum clearance distances designed or measured
for functional insulation smaller values are not allowed
smaller values are allowed
but voltage test obligatory
according to
Minimum clearance for reinforced insulation according to 1,6 x U
Ni
clause 5 and Table A.8
Clause 5 and Table A.8
distances designed or measured
smaller values are not allowed
Step 6 Determination of
Choice of the material group I, II, IIIa, or IIIb
minimum creepage distance
according 2.6 and 4.1
according to 2.6 and 4.1
for the section of the circuit
U from Step 2
Nm
Table A.5, A.6 or A.7
interpolation permitted
PD from Step 4
Minimum creepage distance
Minimum creepage distance for basic insulation
smaller values are not allowed
for functional insulation;
values are for basic insulation distances designed or measured according to Annex C
smaller values are not allowed
Minimum creepage ≥ minimum clearance
distances designed or measured
according to Annex C
Minimum creepage ≥ minimum
clearance
Minimum creepage distance
for reinforced insulation according to 2xU
Nm
smaller values are not allowed
distances designed or measured according to Annex C
Minimum creepage ≥ minimum clearance

Figure G.1 – Determination of minimum clearances and creepage distances (concluded)

---------------------- Page: 7 ----------------------

– 7 – EN 50124-1:2001/A1:2003
G.2.4 Pollution
Table A.4 and Annex E may be used to identify the pollution degree applicable. A definitio
...