Railway applications - Fixed installations - D.C. surge arresters and voltage limiting devices - Part 1: Surge arresters

This European Standard applies to non-linear metal-oxide resistor type surge arresters without spark gaps designed to limit voltage surges on d.c. systems with nominal voltage up to 3 kV.

Bahnanwendungen - Ortsfeste Anlagen - Überspannungsableiter und Spannungsbegrenzungseinrichtungen für Gleichspannungsnetze - Teil 1: Überspannungsableiter

Applications ferroviaires - Installations fixes - Parafoudres et limiteurs de tension pour systèmes à courant continu - Partie 1: Parafoudres

Železniške naprave - Stabilne naprave električne vleke - Prenapetostni odvodniki in napetostni omejilniki za enosmerni tok - 1. del: Prenapetostni odvodniki

Ta evropski standard se uporablja za prenapetostne odvodnike z nelinearnimi upori iz kovinskega oksida brez iskrišč za omejevanje valovnih napetostnih udarov v sistemih enosmernega toka z nazivno napetostjo do 3 kV.

General Information

Status
Published
Publication Date
12-Jan-2012
Current Stage
6060 - Document made available
Due Date
13-Jan-2012
Completion Date
13-Jan-2012

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SLOVENSKI STANDARD
SIST EN 50526-1:2012
01-marec-2012
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SIST EN 50123-5:2003
äHOH]QLãNHQDSUDYH6WDELOQHQDSUDYHHOHNWULþQHYOHNH3UHQDSHWRVWQLRGYRGQLNL
LQQDSHWRVWQLRPHMLOQLNL]DHQRVPHUQLWRNGHO3UHQDSHWRVWQLRGYRGQLNL

Railway applications - Fixed installations - D.C. surge arresters and voltage limiting

devices - Part 1: Surge arresters
Bahnanwendungen - Ortsfeste Anlagen - Überspannungsableiter und
Niederspannungsbegrenzer - Teil 1: Überspannungsableiter

Applications ferroviaires - Installations fixes - Parafoudres et limiteurs de tension pour

systèmes à courant continu - Partie 1: Parafoudres
Ta slovenski standard je istoveten z: EN 50526-1:2012
ICS:
29.120.50 9DURYDONHLQGUXJD Fuses and other overcurrent
PHGWRNRYQD]DãþLWD protection devices
29.280 (OHNWULþQDYOHþQDRSUHPD Electric traction equipment
SIST EN 50526-1:2012 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 50526-1:2012
---------------------- Page: 2 ----------------------
SIST EN 50526-1:2012
EUROPEAN STANDARD
EN 50526-1
NORME EUROPÉENNE
January 2012
EUROPÄISCHE NORM
ICS 29.120.50; 29.280 Supersedes EN 50123-5:2003
English version
Railway applications -
Fixed installations -
D.C. surge arresters and voltage limiting devices -
Part 1: Surge arresters
Applications ferroviaires - Bahnanwendungen -
Installations fixes - Ortsfeste Anlagen -
Parafoudres et limiteurs de tension pour Überspannungsableiter und
systèmes à courant continu - Niederspannungsbegrenzer -
Partie 1: Parafoudres Teil 1: Überspannungsableiter

This European Standard was approved by CENELEC on 2011-10-10. 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 CEN-CENELEC Management Centre 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 CEN-CENELEC Management Centre 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, Turkey 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

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 50526-1:2012 E
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SIST EN 50526-1:2012
EN 50526-1:2012 – 2 –
Contents

Foreword ........................................................................................................................................................... 4

Introduction ....................................................................................................................................................... 5

1 Scope ......................................................................................................................................................... 6

2 Normative references ............................................................................................................................... 6

3 Terms and definitions ............................................................................................................................... 7

4 Characteristics ........................................................................................................................................ 12

4.1 Marking ........................................................................................................................................... 12

4.2 Service conditions ........................................................................................................................... 12

4.3 Requirements ................................................................................................................................. 13

5 Arrester classification ............................................................................................................................ 14

6 Type test .................................................................................................................................................. 14

6.1 General ........................................................................................................................................... 14

6.2 Insulation withstand tests on the arrester housing ......................................................................... 15

6.3 Residual voltage tests ..................................................................................................................... 16

6.4 Charge transfer test ........................................................................................................................ 17

6.5 Operating duty tests ........................................................................................................................ 19

6.6 Short-circuit tests ............................................................................................................................ 24

6.7 Internal partial discharge tests ........................................................................................................ 27

6.8 Bending moment test ...................................................................................................................... 28

6.9 Seal leak rate test ........................................................................................................................... 33

6.10 Environmental tests ........................................................................................................................ 35

7 Routine tests and acceptance tests ...................................................................................................... 36

7.1 Routine tests ................................................................................................................................... 36

7.2 Acceptance tests ............................................................................................................................ 37

Annex A (normative) Flowchart of testing procedure of bending moment ............................................. 38

Annex B (normative) Direct lightning current impulse withstand test .................................................... 39

Bibliography .................................................................................................................................................... 40

Figures

Figure 1 – Impulse current – Rectangular ........................................................................................................ 18

Figure 2 – Power losses of the metal-oxide resistor at elevated temperatures versus time ............................ 20

Figure 3 – Circuit layout for short-circuit test (all leads and venting systems in the same plane) .................... 25

Figure 4 – Example of a test circuit for re-applying pre-failing immediately before applying the short-

circuit test current ..................................................................................................................................... 27

Figure 5 – Thermomechanical preconditioning ................................................................................................ 30

Figure 6 – Example of the arrangement for the thermo-mechanical preconditioning and directions of the

cantilever load .......................................................................................................................................... 31

Figure 7 – Water immersion test ...................................................................................................................... 32

Figure 8 – Definition of mechanical loads (base load = SSL) .......................................................................... 33

Figure 9 – Surge arrester unit ........................................................................................................................... 34

Figure A.1 – Flowchart of testing procedure of bending moment .................................................................... 38

Tables

Table 1 – Arrester classification ....................................................................................................................... 14

Table 2 – Type tests ......................................................................................................................................... 15

Table 3 – Peak currents for switching impulse residual voltage test ................................................................ 17

Table 4 – Parameters for the charge transfer test ............................................................................................ 18

Table 5 – Determination of elevated continuous operating voltage ................................................................. 21

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SIST EN 50526-1:2012
– 3 – EN 50526-1:2012

Table 6 – Test procedure of operating duty test ............................................................................................... 22

Table 7 – Requirements for high current impulses ........................................................................................... 23

Table 8 – Required currents for short-circuit tests ........................................................................................... 25

Table B.1 – Parameters for the direct lightning impulse ................................................................................... 39

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SIST EN 50526-1:2012
EN 50526-1:2012 – 4 –
Foreword

This document (EN 50526-1:2012) has been prepared by SC 9XC, Electric supply and earthing systems for

public transport equipment and ancillary apparatus (Fixed installations), of Technical Committee CENELEC

TC 9X, Electrical and electronic applications for railways.
The following dates are fixed:
• latest date by which this document has
(dop) 2012-10-10
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national
(dow) 2014-10-10
standards conflicting with this
document have to be withdrawn
This document supersedes EN 50123-5:2003.

The existing standard EN 50123-5:2003 covers the case of the old technologies of the gapped arresters with

SiC resistors and of the low voltage limiters (LVL) with gaps. These technologies at present are superseded.

The present standard deals with the new technologies of the gapless metal-oxide arresters and of the LV

limiters for application in the electric railway d.c. fixed installations. Guidance for selection and application of

SA and LVL is missing in the old standard while it is added in the third part of the new standard.

As there is no standard available at the moment for surge arrester on rolling stock it seems convenient for

the WG to note that the same electrical requirements apply for arresters on rolling stock, taking into account

other specific requirements.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights.

__________
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SIST EN 50526-1:2012
– 5 – EN 50526-1:2012
Introduction
This European Standard is in three parts:

- Part 1 deals with metal-oxide arresters without gaps for d.c. railway traction systems (fixed installations)

and is based on EN 60099-4:2004 + A1:2006 + A2:2009;

- Part 2 deals with voltage limiting devices for specific use in d.c. railway traction systems (fixed

installations);

- Part 3 deals with a Guide of application of metal-oxide arresters and of voltage limiting devices.

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SIST EN 50526-1:2012
EN 50526-1:2012 – 6 –
1 Scope

This European Standard applies to non-linear metal-oxide resistor type surge arresters without spark gaps

designed to limit voltage surges on d.c. systems with nominal voltage up to 3 kV.

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 50124-1:2001, Railway applications – Insulation coordination – Part 1: Basic requirements – Clearances

and creepage distances for all electrical and electronic equipment

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

installations

EN 60060-1:2010, High-voltage test techniques - Part 1: General definitions and test requirements

(IEC 60060-1:2010)

EN 60270:2001, High-voltage test techniques – Partial discharge measurements (IEC 60270:2000)

EN 61109:2008, Insulators for overhead lines – Composite suspension and tension insulators for a.c.

systems with a nominal voltage greater than 1 000 V – Definitions, test methods and acceptance criteria

(IEC 61109:2008)

EN ISO 4287:1998, Geometrical Product Specifications (GPS) - Surface texture: Profile method - Terms,

definitions and surface texture parameters (ISO 4287:1997)

EN ISO 4892-1:2000, Plastics - Methods of exposure to laboratory light sources - Part 1: General guidance

(ISO 4892-1:1999)

EN ISO 4892-2:2006, Plastics - Methods of exposure to laboratory light sources - Part 2: Xenon-arc lamps

(ISO 4892-2:2006)

EN ISO 4892-3:2006, Plastics - Methods of exposure to laboratory light sources - Part 3: Fluorescent

UV lamps (ISO 4892-3:2006)
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SIST EN 50526-1:2012
– 7 – EN 50526-1:2012
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
nominal voltage U
designated value for a system
[EN 50163:2004]
3.2
highest permanent voltage U
max1
maximum value of the voltage likely to be present indefinitely
[EN 50163:2004]
3.3
highest non-permanent voltage U
max2
maximum value of the voltage likely to be present for a limited period of time
NOTE Adapted from EN 50163:2004.
3.4
rated insulation voltage U

d.c withstand voltage value assigned by the manufacturer to the equipment or a part of it, characterising the

specified permanent (over five minutes) withstand capability of its insulation
NOTE Adapted from EN 50124-1:2001.
3.5
rated impulse withstand voltage U

impulse voltage value assigned by the manufacturer to the equipment or a part of it, characterising the

specified withstand capability of its insulation against transient overvoltages
NOTE Adapted from EN 50124-1:2001.
3.6
overvoltage

voltage having a peak value exceeding the corresponding peak value of the highest non-permanent voltage

max2
3.7
transient overvoltage

short duration overvoltage of a few (up to 20 ms) milliseconds or less associated with a transient regime.

Two particular transient overvoltages are defined: switching overvoltage and lightning overvoltage

NOTE Adapted from EN 50124-1:2001.
3.8
switching overvoltage

transient overvoltage at any point of the system due to specific switching operation or fault

[EN 50124-1:2001]
3.9
lightning overvoltage
transient overvoltage at any point of the system due to a lightning discharge
[EN 50124-1:2001]
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SIST EN 50526-1:2012
EN 50526-1:2012 – 8 –
3.10
surge arrester
device intended to limit the transient overvoltages to a specified level
3.11
metal-oxide surge arrester

arrester having non-linear metal-oxide resistors connected in series and/or in parallel without any integrated

series or parallel spark gaps
3.12
continuous operating voltage of an arrester U

designated permissible d.c. voltage value that may be applied continuously between the arrester terminals

NOTE Adapted from EN 60099-4:2004.
3.13
rated voltage of an arrester U
voltage by which the arrester is designated

NOTE Because of the particular nature of the d.c. electrical installation dealt with, the rated voltage of a d.c. arrester coincides with

the continuous operating voltage.
3.14
elevated continuous operating voltage U *

test voltage U * that, when applied to new metal-oxide resistor, gives the same power losses as the voltage

U when applied to aged metal-oxide resistors
3.15
lightning impulse protection level U
the maximum residual voltage for the nominal discharge current
3.16
switching impulse protection level U
maximum residual voltage at the specified switching impulse current
3.17
charge transfer capability Q

maximum charge per impulse that can be transferred during the charge transfer test and during the operating

duty test
3.18
discharge current of an arrester
impulse current which flows through the arrester
3.19
nominal discharge current of an arrester I
peak value of lightning current impulse which is used to classify an arrester
[EN 60099-4:2004]
3.20
high current impulse of an arrester

peak value of discharge current having a 4/10 µs impulse shape which is used to test the stability of the

arrester on direct lightning strokes
[EN 60099-4:2004]
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SIST EN 50526-1:2012
– 9 – EN 50526-1:2012
3.21
steep current impulse

current impulse with a virtual front time of 1 µs with limits in the adjustment of equipment such that the

measured values are from 0,9 µs to 1,1 µs and the virtual time to half-value on the tail is not longer than

20 µs
NOTE Adapted from EN 60099-4:2004.
3.22
lightning current impulse

8/20 current impulse with limits on the adjustment of equipment such that the measured values are from 7 µs

to 9 µs for the virtual front time and from 18 µs to 22 µs for the time to half-value on the tail

[EN 60099-4:2004]
3.23
direct lightning current impulse
impulse defined by the charge Q and the peak value of the current impulse I
imp
3.24
switching current impulse of an arrester I

peak value of discharge current having a virtual front time greater than 30 µs but less than 100 µs and a

virtual time to half value on the tail of roughly twice the virtual front time
[EN 60099-4:2004]
3.25
reference current of an arrester I
ref

d.c. current defined by the manufacturer used to determine the reference voltage of the arrester

NOTE Adapted from EN 60099-4:2004
3.26
reference voltage of an arrester U
ref

d.c. voltage across the arrester when the reference current is flowing through it

NOTE Adapted from EN 60099-4:2004.
3.27
residual voltage of an arrester U
res

peak value of voltage that appears between the terminals of an arrester during the passage of discharge

current
[EN 60099-4:2004]
3.28
rated short circuit current of an arrester I

maximum current that may flow in case of an arrester failure for a specified time

3.29
shed

insulating part projecting from the housing, intended to increase the creepage distance

[EN 60099-4:2004]
3.30
porcelain-housed arrester
arrester using porcelain as housing material, with fittings and sealing systems
[EN 60099-4:2004]
3.31
polymer-housed arrester
arrester using polymeric and/or composite materials for housing
NOTE Adapted from EN 60099-4.2004.
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SIST EN 50526-1:2012
EN 50526-1:2012 – 10 –
3.32
bending moment

horizontal force acting on the arrester housing multiplied by the vertical distance between the mounting base

(lower level of the flange) of the arrester housing and the point of application of the force

[EN 60099-4:2004]
3.33
torsional loading

horizontal force at the top of a vertical mounted arrester housing which is not applied to the longitudinal axis

of the arrester
NOTE Adapted from EN 60099-4:2004.
3.34
breaking load

force perpendicular to the longitudinal axis of a porcelain-housed arrester leading to mechanical failure of the

arrester housing
[EN 60099-4:2004]
3.35
mean breaking load
MBL
the average breaking load for porcelain arresters determined from tests
NOTE Adapted from EN 60099-4: A2:2009.
3.36
specified long-term load
SLL

force perpendicular to the longitudinal axis of an arrester, allowed to be continuously applied during service

without causing any mechanical damage to the arrester
[EN 60099-4: A2: 2009]
3.37
specified short-term load
SSL

greatest force perpendicular to the longitudinal axis of an arrester, allowed to be applied during service for

short periods and for relatively rare events (for example, short-circuit current loads, extreme wind gusts)

without causing any mechanical damage to the arrester
[EN 60099-4: A2: 2009]
3.38
non-linear metal-oxide resistor

part of the surge arrester which, by its non-linear voltage versus current characteristic, acts as a low

resistance to overvoltages, thus limiting the voltage across the arrester terminals, and as a high resistance at

normal operating voltage
NOTE Adapted from EN 60099-4:2004.
3.39
pressure-relief device of an arrester

means for relieving internal pressure in an arrester and preventing violent shattering of the housing following

prolonged passage of fault current or internal flashover of the arrester
[EN 60099-4:2004]
3.40
internal part
metal-oxide resistor element with supporting structure
[EN 60099-4:2004]
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SIST EN 50526-1:2012
– 11 – EN 50526-1:2012
3.41
seal (gas/water tightness)

ability of an arrester to avoid ingress of matter affecting the electrical and/or mechanical behaviour into the

arrester
[EN 60099-4:2004]
3.42
disruptive discharge

phenomena associated with the failure of insulation under electric stress, which include a collapse of voltage

and the passage of current

NOTE 1 The term applies to electrical breakdowns in solid, liquid and gaseous dielectric, and combinations of these.

NOTE 2 Adapted from EN 60099-4:2004.
3.43
puncture (breakdown)
disruptive discharge through a solid
[EN 60099-4:2004]
3.44
flashover
disruptive discharge over a solid surface
[EN 60099-4:2004]
3.45
impulse

unidirectional wave of voltage or current which without appreciable oscillations rises rapidly to a maximum

value and falls, usually less rapidly, to zero with small, if any, excursions of opposite polarity

NOTE The parameters which define a voltage or current impulse are polarity, peak value, front time and time to half value on the tail.

[EN 60099-4:2004]
3.46
type test (design test)
conformity test made on one or more items representative of the production
[IEV 151-16-16]
3.47
routine test
conformity test made on each individual item during or after manufacture
[IEV 151-16-17]
3.48
acceptance test

contractual test to prove to the customer that the item meets certain conditions of its specification

[IEV 151-16-23]
3.49
prospective short circuit current

current which would flow in a circuit if it were short-circuited by a link of negligible impedance

NOTE Adapted from EN 60099-4:2004.
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SIST EN 50526-1:2012
EN 50526-1:2012 – 12 –
4 Characteristics
4.1 Marking

Surge arresters shall be identified by the following minimum information which shall appear on the rating

plate (nameplate):
– rated voltage Ur = Uc;
– nominal discharge current In in kA;
– rated short circuit current Is in kA;
– manufacturer's name or trademark, type and identification;
– year of manufacture;
– serial number;
– arrester class

NOTE The rated voltage of a d.c. metal-oxide arresters coincides with continuous operating voltage as per the operating duty test.

Conditions in a.c. systems:

According to EN 60099-4:2004, 3.8, the rated voltage of a surge arrester is defined as the maximum permissible r.m.s. value of power-

frequency voltage between its terminals at which it is designed to operate correctly under long-term overvoltage conditions as

established in the operating duty test. The rated voltage is the 10 s power-frequency voltage used in the operating duty test after high-

current or long-duration impulses. U is applied for 30 min immediately after the application of rated voltage in the operating duty test

where thermal stability has to be demonstrated. Typically the ratio between rated voltage and Uc is about 1,25 for surge arresters in a.c.

systems corresponding to a specific long-term overvoltage, which may occur during fault conditions in the a.c. system.

Conditions in d.c. systems:

According to EN 50163 the supply voltages of traction systems are defined. The highest non-permanent voltage U is defined for

max2

durations from 1 s to 5 min. By selection of the surge arrester by U > U , the operating duty test as specified in 6.5 covers all effects

c max2

of long-term overvoltages longer than 1 s with significant margin. No higher long-term overvoltages, which could be assigned to a “rated

voltage“ occur in d.c. systems.
4.2 Service conditions
4.2.1 Normal service conditions

Surge arresters which conform to this European Standard shall be suitable for operation under the following

normal service conditions:
1) ambient temperature within the range of -40 °C to +40 °C;
2) solar radiation (see 4.8 of EN 50125-2:2002);
3) altitude not exceeding 2 000 m (from EN 50124-1);

4) pollution not exceeding PD 1 for indoor installations and PD 4 for outdoor installations as given in

EN 50124-1;

5) installation in the vicinity of a rail track on foundations designed so as to damp the main effects of the

passage of the trains. Nevertheless a limited vibration or limited shocks may affect the equipment,

which shall be capable of operating satisfactorily when subjected to the following conventional

accelerations separately applied:
– g : vertical acceleration: 5 m/s²;
– g : horizontal acceleration: 5 m/s².

6) Surge arrester shall comply with condition for class W3 (wind speed 32m/s) as defined in 4.4.1 of

EN 50125-2:2002;
4.2.2 Abnormal service conditions

The following are typical abnormal service conditions which may require special consideration in the

manufacture or application of surge arresters and should be called to the attention of the manufacturer:

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SIST EN 50526-1:2012
– 13 – EN 50526-1:2012
a) temperature in excess of +40 °C or below -40 °C;
b) application at altitudes higher than 2 000 m;

c) fumes or vapours which may cause deterioration of insulating surface or mounting hardware;

d) excessive contamination by smoke, dirt, salt spray or other conducting materials;

e) excessive exposure to moisture, humidity, dropping water or steam;
f) live washing of arrester;
g) explosive mixtures of dust, gases or fumes;

h) abnormal mechanical conditions (earthquakes, vibrations, high ice loads, high cantilever stresses);

i) unusual transportation or storage;
j) heat sources near the arrester;
k) non-vertical erection and suspended erection;
l) torsional loading of the arrester;
m) tensile loading of the arrester;
n) use of the arrester as a mechanical support.
4.3 Requirements
4.3.1 Insulation withstand of the arrester housing

The insulation of the arrester housing shall be coordinated with the arrester protective characteristics. Tests

shall be performed according to 6.2.
4.3.2 Reference voltage

Measurement of reference voltage is necessary for the selection of a correct test sample in the operating

duty test, see 6.5.

The reference voltage of a d.c. surge arrester is measured at a specific reference current, The reference

current is typically in the range of 0,05 mA to 1,0 mA per square centimetre of disc area for single column

arresters.

The minimum reference voltage of the arrester at the reference current used for routine tests shall be

specified and published in the manufacturer’s data.
4.3.3 Residual voltages

The maximum residual voltages for a given design and for all specified currents and wave shapes shall be

obtained from the type test data and from the maximum residual voltage at a lightning impulse current used

for routine test as specified and published by the manufacturer.

The maximum residual voltage of a given arrester design for any current and wave shape shall be calculated

from the residual voltage of samples tested during type test multiplied by a specific scale factor. This scale

factor is equal to the ratio of the declared maximum residual voltage, as checked during the routine test, to

the measured residual voltage of the samples at the same current and wave shape.
4.3.4 Internal partial discharges

The internal partial discharges of the arrester energized at 1,05 times its continuous operating

...

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