SIST EN 50123-5:2003

Railway applications - Fixed installations - D.C. switchgear -- Part 5: Surge arresters and low-voltage limiters for specific use in d.c. systems

Applies, in particular, to surge arresters consisting of single or multiple spark gaps in series with one or more non-linear resistors. This consolidated version consists of the third edition (1991)    and its amendment 1 (1999). Therefore, no need to order amendment in addition to this publication.

Bahnanwendungen - Ortsfeste Anlagen - Gleichstrom-Schalteinrichtungen -- Teil 5: Überspannungsableiter und Niederspannungsbegrenzer für spezielle Verwendung in Gleichstromsystemen

Applications ferroviaires - Installations fixes - Appareillage à courant continu -- Partie 5: Parafoudres et limiteurs de tension pour utilisation spécifique dans les systèmes à courant continu

S'applique particulièrement aux parafoudres comportant un éclateur simple ou multiple en série, avec une ou plusieurs résistances variables.  Cette version consolidée comprend la troisième édition (1991) et son amendement 1 (1999). Il n'est donc pas nécessaire de commander   l'amendement avec cette publication.

Železniške naprave – Stabilne naprave električne vleke – Stikalne naprave za enosmerni tok – 5. del: Prenapetostni odvodniki in nizkonapetostni omejilniki za izključno uporabo v enosmernih sistemih

General Information

• Status: Withdrawn
• Publication Date: 30-Apr-2003
• Withdrawal Date: 25-Jan-2012
• ICS: 29.130.99 - Other switchgear and controlgear
• ICS: 29.280 - Electric traction equipment
• Technical Committee: ŽEN - Electrical applications for railways
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 25-Jan-2012
• Due Date: 17-Feb-2012
• Completion Date: 26-Jan-2012
• Ref Project: EN 50123-5:2003 - Railway applications - Fixed installations - D.C. switchgear - Part 5: Surge arresters and low-voltage limiters for specific use in d.c. systems

Relations

• Replaced By: SIST EN 50526-1:2012 - Railway applications - Fixed installations - D.C. surge arresters and voltage limiting devices - Part 1: Surge arresters
• Effective Date: 28-Jan-2023
• Revised: SIST EN 50526-1:2012 - Railway applications - Fixed installations - D.C. surge arresters and voltage limiting devices - Part 1: Surge arresters
• Effective Date: 06-May-2014
• Replaces: SIST EN 50123-5:1998/A1:1999 - Railway applications - Fixed installations - D.C. switchgear -- Part 5: Surge arresters and low-voltage limiters for specific use in d.c. systems
• Effective Date: 28-Jan-2023
• Replaces: SIST EN 50123-5:1998 - Railway applications - Fixed installations - D.C. switchgear -- Part 5: Surge arresters and low-voltage limiters for specific use in d.c. systems
• Effective Date: 28-Jan-2023
• Replaces: SIST EN 50123-5:1998 - Railway applications - Fixed installations - D.C. switchgear -- Part 5: Surge arresters and low-voltage limiters for specific use in d.c. systems
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 50123-5:2003
01-maj-2003
1DGRPHãþD
SIST EN 50123-5:1998
SIST EN 50123-5:1998/A1:1999
äHOH]QLãNHQDSUDYH±6WDELOQHQDSUDYHHOHNWULþQHYOHNH±6WLNDOQHQDSUDYH]D
HQRVPHUQLWRN±GHO3UHQDSHWRVWQLRGYRGQLNLLQQL]NRQDSHWRVWQLRPHMLOQLNL]D
L]NOMXþQRXSRUDERYHQRVPHUQLKVLVWHPLK
Railway applications - Fixed installations - D.C. switchgear -- Part 5: Surge arresters and
low-voltage limiters for specific use in d.c. systems
Bahnanwendungen - Ortsfeste Anlagen - Gleichstrom-Schalteinrichtungen -- Teil 5:
Überspannungsableiter und Niederspannungsbegrenzer für spezielle Verwendung in
Gleichstromsystemen
Applications ferroviaires - Installations fixes - Appareillage à courant continu -- Partie 5:
Parafoudres et limiteurs de tension pour utilisation spécifique dans les systèmes à
courant continu
Ta slovenski standard je istoveten z: EN 50123-5:2003
ICS:
29.130.99 Druge stikalne in krmilne Other switchgear and
naprave controlgear
29.280 (OHNWULþQDYOHþQDRSUHPD Electric traction equipment
SIST EN 50123-5:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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

SIST EN 50123-5:2003

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

SIST EN 50123-5:2003
EUROPEAN STANDARD EN 50123-5
NORME EUROPÉENNE
EUROPÄISCHE NORM February 2003

ICS 29.120.60; 45.020 Supersedes EN 50123-5:1997 + A1:1999


English version


Railway applications –
Fixed installations - D.C. switchgear
Part 5: Surge arresters and low-voltage limiters
for specific use in d.c. systems


Applications ferroviaires –  Bahnanwendungen –
Installations fixes – Ortsfeste Anlagen –
Appareillage à courant continu Gleichstrom-Schalteinrichtungen
Partie 5: Parafoudres et limiteurs Teil 5: Überspannungsableiter und
de tension pour utilisation spécifique Niederspannungsbegrenzer
dans les systèmes à courant continu für spezielle Verwendung
in Gleichstromsystemen






This European Standard was approved by CENELEC on 2002-09-01. 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, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, 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 50123-5:2003 E

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

SIST EN 50123-5:2003
EN 50123-5:2003 - 2 -
Foreword

This European Standard was prepared by SC 9XC, Electric supply and earthing systems for
public transport equipment and ancillary apparatus (fixed installations), of the Technical
Committee CENELEC TC 9X, Electrical and electronic applications for railways.

The text of the draft was submitted to the Unique Acceptance Procedure and was approved
by CENELEC as EN 50123-5 on 2002-09-01.

This European Standard supersedes EN 50123-5:1997 + A1:1999.

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) 2003-09-01

- latest date by which the national standards conflicting
 with the EN have to be withdrawn (dow) 2005-09-01

This Part 5 is to be used in conjunction with EN 50123-1:2003, with EN 60099-1:1994 and with
EN 60099-4:1993.
Annexes designated “informative” are given for information only.
In this standard, annexes A and B are informative.
_____________

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

SIST EN 50123-5:2003
- 3 - EN 50123-5:2003
Contents

Page

Introduction . 5
1 Common matters . 6
1.1 Scope . 6
1.2 Normative references. 6
2 Non-linear resistor type gapped surge arresters. 7
2.1 General. 7
2.2 Definitions . 7
2.3 Marking . 7
2.4 Preferred ratings. 7
2.5 Requirements. 8
2.6 General testing procedure. 9
2.7 Routine and acceptance tests . 9
2.8 Type tests. 8
3 Artificial pollution testing of surge arresters. 14
4 Metal-oxide surge arresters without gaps. 15
4.1 General. 15
4.2 Definitions . 15
4.3 Marking . 15
4.4 Preferred ratings. 15
4.5 Requirements. 16
4.6 General testing procedure. 17
4.7 Type tests. 17
4.8 Routine and acceptance tests . 22
5 Low-voltage limiters for specific use in d.c. systems. 25
5.1 General. 25
5.2 Definitions . 25
5.3 Marking and classification. 25
5.4 Preferred ratings. 25
5.5 Requirements. 26
5.6 Routine and acceptance tests . 27
5.7 Type tests. 27

Annex A (informative) Typical information given with enquiries and tenders
valid for all types covered in this European Standard . 30

Annex B (informative) High voltage filters for protection against voltage surges . 32

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

SIST EN 50123-5:2003
EN 50123-5:2003 - 4 -
Figure 1 - Simulated d.c. voltage test circuit for operating duty test for surge arresters
by using an equivalent energy impulse current generator .13
Figure 4.1 - Operating duty test on gapless arresters for use in d.c. networks
(see 4.7.5.4) .24
Figure 4.2 - Thermal stability test on gapless arresters for use in d.c. networks
(see 4.8.2.2) .24
Figure B.1 - Typical diagram of the filter .32

Table 2.1A - Preferred voltage ratings (kV).7
Table 2.1B - Preferred protective voltage levels (kV ) .8
cr
Table 2.1C - Preferred nominal discharge currents (kA) .8
Table 2.3 - Arrester test requirements .10
Table 2.4 - High-current impulse test.12
Table 4.1 - Preferred voltage ratings (kV).15
Table 4.2 - Preferred protective voltage levels (kV ) .16
cr
Table 4.3 - Preferred nominal discharge currents (kA).16
Table 4.4 - Arrester test requirements .18
Table 5.1 - Preferred voltage ratings (V).25
Table 5.2 - Requirements for LVL.26
Table 5.3 - Type tests .27
Table B.1 - Preferred values for charge resistor.33
Table B.2 - Preferred values for capacitor.33
Table B.3 - Preferred values for discharge resistor rating.34

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SIST EN 50123-5:2003
- 5 - EN 50123-5:2003
Introduction

EN 50123-5 is divided into five clauses as follows:

1 common matters;
2 non-linear resistor type gapped surge arresters (based on EN 60099-1);
3 artificial pollution testing of surge arresters: under consideration;
4 metal-oxide surge arresters without gaps (based on EN 60099-4) and surge protective
devices (based on EN 61643-11);
5 low-voltage limiters.

Clauses 2 and 4 of this standard shall be read in conjunction with the documents mentioned in
1.2.

In particular clauses 4 to 8 and Annex B, Annex D and Annex E of EN 60099-1 are referred to
in clause 2 of EN 50123-5, unless explicitly otherwise indicated in this European Standard.

For gapless surge arresters and surge protective devices the appropriate portions of EN 60099-4
and EN 61643-11 respectively are quoted in clause 4 of this EN 50123-5, and apply.

NOTE 1  Only those clauses and subclauses which are modified in respect to the above-mentioned CENELEC and
IEC publications are mentioned in this document. The National Committees may copy the unchanged portions of the
IEC 60099 publications referred altering the type face as necessary.

NOTE 2  The numbering of this EN 50123-5 follows the following criteria:
- the first number identifies the five clauses of this standard;
- the remaining numbers, for clause 2 and clause 4, are taken unchanged from EN 60099-1 and EN 60099-4
respectively.

Annex A gives typical information required during enquiry and tenders. Annex B describes a
typical solution for high voltage filters against voltage surges.

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SIST EN 50123-5:2003
EN 50123-5:2003 - 6 -
1 Common matters

1.1  Scope

Clauses 1, 2, 3 and 4 of this European Standard cover particular requirements for surge arresters
(following named arresters) for specific use in fixed installations of d.c. traction systems. These
are surge arresters consisting of one or more non-linear resistors which may be in series with
single or multiple spark gaps.

Low-voltage limiters are covered under clause 5. These are protective devices mainly used in
fixed installations of d.c. traction systems to connect certain portions of the circuit, when, owing
to an abnormal situation, the voltage across the device exceeds a predetermined limited value.
They may be associated with other devices such as contactors for self-restoring arrangements.
They are not used in general to provide surge protection.

The following are the main uses of low-voltage limiters (LVL):
- connection to the rail of metallic masses;
- protection of rail circuits;
- earthing of rails in the substation;
- protection of cathodic circuits;
- protection of cable shields.

1.2  Normative references
This European Standard incorporates by dated or undated references, provisions from other
publications. These normative references are cited at the appropriate places in the text and
the publications are listed hereafter. For dated references, subsequent amendments to or
revisions of any of these publications apply to this European Standard only when
incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 50123-1 2003 Railway applications – Fixed installations - D.C. switchgear –
Part 1: General

EN 50125-2 2002 Railway applications - Environmental conditions for equipment - Part 2:
Fixed electrical installations

EN 60099-1 1994 Surge arresters -- Part 1: Non-linear resistor type gapped surge arresters for
a.c. systems (IEC 60099-1:1991)

EN 60099-4 1993 Surge arresters -- Part 4: Metal-oxide surge arresters without gaps for a.c.
systems (IEC 60099-4:1991)

EN 61643-11 2002 Low-voltage surge protective devices – Part 11: Surge protective devices
connected to low voltage power systems – Requirements and tests
 (IEC 61643-1:1998, mod. + corrigendum December 1998)

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SIST EN 50123-5:2003
- 7 - EN 50123-5:2003
2 Non-linear resistor type gapped surge arresters

2.1 General

See clause 1.

NOTE  Gapped surge arresters should not be used for new installations

2.2 Definitions

For the purposes of this European standard the terms and definitions given in clause 3 of
EN 50123-1, as well as the definitions in section 2 of EN 60099-1 apply.

2.3 Marking

Gapped surge arresters shall be identified by the following minimum information which shall
appear either on the rating plate (nameplate) or, if a nameplate in accordance with EN 60099-1 is
provided, separately with the arrester or on a paper sheet provided by the manufacturer together
with the arrester:
- compliance with EN 50123-5;
- type: gapped - suitable for d.c. traction systems;
- rated voltage U ;
r
- protective voltage level U ;
p
- nominal discharge current I ;
n
- pressure relief class in kA (if any);
- manufacturer's name or trademark, type and identification;
- year of manufacture;
- serial number.

NOTE  Information to be given in the enquiry or tender may be guided by Annex A of this standard or by Annex B
of EN 60099-1.

2.4 Preferred ratings

A document giving a guidance in the selection of the characteristics which ensure the correct
protection of the circuit is in preparation.

2.4.1 Preferred voltage ratings (U )
r

Preferred values of rated voltages for gapped arresters shall be as listed in Table 2.1A.

Table 2.1A - Preferred voltage ratings (kV)


0,750 1 2 4

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SIST EN 50123-5:2003
EN 50123-5:2003 - 8 -
2.4.2 Preferred protective voltage levels (U )
p
Preferred protective voltage levels for gapped arresters shall be as listed in Table 2.1B.

Table 2.1B - Preferred protective voltage levels (kV )
cr


3,0 4,5 5,0 6,0 8,0 10 12 15 18

20 25 30 35 40


2.4.3 Preferred nominal discharge currents (I )
n

The preferred nominal discharge currents, are as listed in Table 2.1C.

Table 2.1C - Preferred nominal discharge currents (kA)


20 10 5 2,5


2.4.4 Service requirements

Where service requirements differ from those defined as "normal" either in clause 4 and Annex B
of EN 50123-1 (for indoor arresters) or in EN 60099 series (for outdoor arresters), the purchaser
shall state this fact in the tender specification. Where a d.c. surge arrester is suitable for use in
service requirements different from those defined as "normal" in the above mentioned
documents, the manufacturer shall state this in the tender specification.

2.5 Requirements

See section 5 of EN 60099-1 except for the following.

2.5.4 Switching impulse sparkover voltage

No limits for the maximum switching impulse sparkover voltage have been specified. The test
under 2.8.3.5 is considered an investigation test, i.e. a test carried out by agreement between
purchaser and supplier for gaining experience, without reference to the contractual obligations.
NOTE  The switching phenomena on d.c. systems are under consideration.

2.5.6 Not applicable.

2.5.8 Long-duration current withstand

Arresters shall withstand the long-duration current impulse test of 2.8.5.3 and Table 6 of
EN 60099-1. The average dry power-frequency sparkover voltage of 2.8.2 recorded before and
after this test shall not have changed by more than 10 %.

NOTE  The switching phenomena on d.c. systems are under consideration.

---------------------- Page: 10 ----------------------

SIST EN 50123-5:2003
- 9 - EN 50123-5:2003
2.6 General testing procedure

See section 6 of EN 60099-1.

2.7 Routine and acceptance tests

NOTE  The term "acceptance test" is under revision.

2.7.1 Routine tests

The minimum requirement for the routine test to be made by the manufacturer shall be the dry
power-frequency sparkover test (see 2.8.2).

2.7.2 Acceptance tests

When the purchaser specifies acceptance tests in the purchase agreement, the following tests
shall be made on the nearest higher whole number to the cube root of the number of arresters to
be supplied:

a) dry power-frequency voltage sparkover test on the complete arrester (see 2.8.2);

b) standard lightning impulse sparkover test on the complete arrester (see 2.8.3.2);

c) only when specifically agreed between the manufacturer and the purchaser, residual voltage
shall be determined on the complete arrester at a discharge current of not less than 0,25 times
the nominal discharge current (see 2.8.4).

Any alteration in the number of samples or type of tests shall be specifically negotiated between
the manufacturer and the purchaser.

2.8 Type tests

See section 8 of EN 60099-1 except for the following.

2.8.1 General

Same as in 8.1 of EN 60099-1, except for Table 3 which shall be substituted by the following
Table 2.3 applicable for any standard discharge current.

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SIST EN 50123-5:2003
EN 50123-5:2003 - 10 -
Table 2.3 - Arrester test requirements

Test Subclause
Power-frequency voltage sparkover test 2.8.2
Standard lightning voltage sparkover test 2.8.3.2
Front-of-wave-voltage sparkover test 2.8.3.4
Residual voltage test 2.8.4
Current impulse withstand:
- High-current 2.8.5.2
- Long-duration 2.8.5.3
Operating duty test 2.8.6
Pressure relief test 2.8.7
Arrester disconnector (when fitted) 2.8.8

2.8.2 Power-frequency voltage sparkover test

Dry and wet tests shall be made in accordance with 6.1, 6.2 and 6.3 of EN 60099-1 and 2.8.1 on
three complete arresters of each voltage rating tested.

The performance for other voltage ratings of the same design (as defined in 2.8.1) within ± 25 %
of a test sample rating can be determined by adjusting the voltage level in proportion to the
voltage ratings.

The voltage applied to the arrester shall be switched on at a value low enough to avoid sparkover
of arrester by resulting switching surge and risen rapidly at a uniform rate until sparkover of the
series gap occurs. The time during which the voltage is allowed to exceed the rated voltage of
the arrester shall be in the range of 2 s to 5 s when testing arresters using grading resistors which
are subject to damages by overheating if the applied voltage exceeds the rated voltage for too
long. After sparkover, the test voltage shall be switched off as rapidly as possible, preferably by
automatic tripping and in any case within 0,5 s. If it is difficult to measure the rapidly increasing
voltage with an indicating type of instrument, a high speed recorder or an oscillograph shall be
used. The manufacturer shall be consulted about the permissible test procedure.

The load imposed on the testing circuit by a surge arrester having non-linear grading resistors of
high conductivity gives rise to harmonics, and the test-circuit shall have a sufficiently low
impedance to maintain the waveform of the voltage across the arrester within the limits specified
in HD 588.1.

The voltage shall be applied not less than 5 times, with an interval of about 10 s between
successive applications.

The average sparkover value of the five tests is adopted as the power-frequency sparkover
voltage for purposes of a comparison of tests made before and after other type tests.

---------------------- Page: 12 ----------------------

SIST EN 50123-5:2003
- 11 - EN 50123-5:2003
NOTE 1  By agreement between purchaser and supplier an additional test may be carried out by applying a d.c.
voltage, with the same procedures. The rate of increase of the voltage shall be approximately 10 V/s. The d.c.
voltage value shall have the same peak value as the peak value of a sinusoidal power frequency test level as required
in EN 50124-1.

NOTE 2  When the arrester is provided with an enclosure, the test shall be carried out with such enclosure.

2.8.3 Voltage impulse sparkover tests

2.8.3.2 Standard lightning impulse sparkover test

With the test sample arrester in the circuit, the impulse generator is adjusted to give a
1,2/50 voltage waveshape and a peak value of protective voltage level U . With this adjustment,
p
five positive and five negative impulses shall be applied to the tested arrester and the series gaps
of the arrester shall sparkover on every impulse. If in either series of five impulses, the gaps fail
to sparkover once only, an additional ten impulses of that polarity shall be applied ant the gaps
shall sparkover on all of these impulses.

The time interval between the start of the wave and instant of sparkover is immaterial in this test.

The tolerances on the adjustment of the testing equipment shall be such that the measured values
lie within the following limits:
a) between 97 % and 100 % or the specified peak values;
b) from 0,85 µs to 1,6 µs for the virtual duration of the wavefront;
c) from 40 µs to 60 µs for the time to half value on the wavetail.

Oscillations on the first part of the wavefront (below 50 %) shall not exceed 10 % of the peak
value. Small oscillations near the peak of the impulse are permissible provided that their
amplitude is less than 5 % of the peak value. Measurement shall be made at the peak of the
oscillations.

2.8.3.4 Front-of-wave impulse sparkover test

Using a voltage impulse with a virtual steepness of front equal to 10 kV/µs, five positive and five
negative impulses shall be applied to the arrester and the sparkover voltage is determined from
voltage-time oscillograms made during each test. On none of the impulses shall the sparkover
voltage exceed 1,15 U .
p

It is permissible to use the point of intersection of the curve specified in 2.8.3.3 with a line
representing the virtual steepness of front specified for determining the maximum front-of-wave
sparkover voltage of the tested arrester provided there are at least five positive and five negative
sparkover test points within ± 0,1 µs of the line representing the prescribed steepness. This is
illustrated in Figure 1 of EN 60099-1.

2.8.3.5 Switching impulse sparkover-voltage/time curve test

As indicated in 2.5.4, this test is by agreement between purchaser and supplier and is for
information purposes.

Test procedure and test values are subject to agreement, but 8.3.5 of EN 60099-1 may assist.

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SIST EN 50123-5:2003
EN 50123-5:2003 - 12 -
2.8.4 Measurement of residual voltage

2.8.4.1 Lightning impulse residual voltage

Add to the text of 8.4.1 of EN 60099-1:

The maximum residual voltage at nominal discharge current shall be U .
p

2.8.4.2 Not applicable

2.8.5 Current impulse withstand test

2.8.5.1 General

Each of these tests shall be made in accordance with 2.7.1 and 2.8.1 on three new complete
arresters which have not been subjected to any test except those specified for evaluation
purposes. If an arrester disconnector is built into the design of the arrester under consideration,
these tests shall be made with the disconnector in operable condition.

2.8.5.2 High-current impulse test

Same text as in 8.5.2 of EN 60099-1, but Table 4 shall be replaced by the following Table 2.4.

Table 2.4 - High-current impulse test


Nominal discharge current I
n
(8/20 µs)                    kA 2,5 5 10 20

Peak value of high-current
(4/10 µs)                    kA 40 65 100 100

2.8.5.3 Long-duration current impulse test

8.5.3.1 of EN 60099-1 is valid as far as applicable according to the following requirements.

8.5.3.2 of EN 60099-1 is not applicable in this European Standard.

In 8.5.3.3 and in Table 6 of EN 60099-1, mention of light-duty and to series A and B shall be
omitted. The values given in Table 6 for I = 10 kA are applicable also to I = 20 kA.
n n

2.8.6 Operating-duty test

This is a test in which service conditions are simulated by the application to the arrester of
20 current impulses, in groups of 5, equal to the nominal discharge current I , while it is
n
permanently energized by a d.c. power supply of a voltage corresponding to U . annex E of
r
EN 60099-1 describes a typical test-circuit where an a.c. power source is used.

---------------------- Page: 14 ----------------------

SIST EN 50123-5:2003
- 13 - EN 50123-5:2003
To simulate a d.c. source a capacitor bank can be used provided that the voltage shall be less than
95 % of U during the test. Figure 1 shows a typical test circuit for this purpose.
r

The test shall be performed on a complete arrester.

In case of difficulties in arranging the test, the use of an a.c. voltage, having the same peak value
as U is subject to agreement between purchaser and supplier.
r

It is not required that the tested arrester be energized between groups of impulses.

Second, fourth and following paragraphs of 8.6 of EN 60099-1 apply, when consistent with the
above requirements.

REPARTITION RESISTOR FOR THE DIODE
PROTECTION DIODE
PROTECTION DIODE FOR IMPULSE GENERATOR
rectifier DC voltage source impulse current generator
≅ µ
L 10 H
SPECIMEN
µ Ω µ
2400 F 32 M C = 12,5 F
Z
UNDER TEST
µ Ω Ω
2400 F 1 k 0,01 shunt FOR DC + IMPULSE CURRENT
≅ Ω
Rc 1
Ω
0,05 shunt FOR IMPULSE GENERATOR CURRENT
AC CIRCUIT DC CIRCUIT DIVIDER SURGE CIRCUIT


Figure 1 - Simulated d.c. voltage test circuit for operating duty test for surge arresters
by using an equivalent energy impulse current generator


NOTE  The forward voltage of the protection diode should not exceed 1 % of the test voltage, otherwise it will
reduce the severity of the test current.

2.8.7 Pressure relief test

This is a type test, applicable to all arresters, whether provided or not with a pressure relief
device, which produces a fault within the arrester, when the arrester is supplied from a d.c.
source. A suitable test procedure shall be by agreement between purchaser and supplier, based
on 8.7 of EN 60099-1.

The arrester is deemed to have passed the test if the housing remains intact or if it breaks non-
explosively and if all parts of the arr
...