IEC TS 62271-210:2013

High-voltage switchgear and controlgear - Part 210: Seismic qualification for metal enclosed and solid-insulation enclosed switchgear and controlgear assemblies for rated voltages above 1 kV and up to and including 52 kV

IEC/TS 62271-210:2013 applies to metal enclosed switchgear and controlgear assemblies complying with IEC 62271-200 for metal enclosed and IEC 62271-201 for solid-insulation enclosed, ground or floor mounted, intended to be used under seismic conditions.

Appareillage à haute tension - Partie 210: Qualification sismique pour ensembles d'appareillage sous enveloppe métallique pour tensions assignées supérieures à 1 kV et inférieures ou égales à 52 kV

La CEI/TS 62271-210:2013 s'applique à des ensembles d'appareillage sous enveloppe métallique satisfaisant à la CEI 62271-200 pour les enveloppes métalliques et à la CEI 62271-201 pour les enveloppes isolées. Ces ensembles d'appareillage sont montés au sol ou sur le plancher d'un bâtiment et sont destinés à être utilisés dans des conditions sismiques.

General Information

• Status: Published
• Publication Date: 05-Feb-2013
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.130.10 - High voltage switchgear and controlgear
• Technical Committee: SC 17C - Assemblies
• Current Stage: PPUB - Publication issued
• Start Date: 06-Feb-2013
• Completion Date: 06-Feb-2013

Standards Content (sample)

IEC/TS 62271-210
Edition 1.0 2013-02
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
High-voltage switchgear and controlgear –
Part 210: Seismic qualification for metal enclosed and solid-insulation enclosed
switchgear and controlgear assemblies for rated voltages above 1 kV and up to
and including 52 kV
Appareillage à haute tension –
Partie 210: Qualification sismique pour ensembles d'appareillage sous
enveloppe métallique pour tensions assignées supérieures à 1 kV et inférieures
ou égales à 52 kV
IEC/TS 62271-210:2013
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC/TS 62271-210
Edition 1.0 2013-02
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
High-voltage switchgear and controlgear –
Part 210: Seismic qualification for metal enclosed and solid-insulation enclosed
switchgear and controlgear assemblies for rated voltages above 1 kV and up to
and including 52 kV
Appareillage à haute tension –
Partie 210: Qualification sismique pour ensembles d'appareillage sous
enveloppe métallique pour tensions assignées supérieures à 1 kV et inférieures
ou égales à 52 kV
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX U
ICS 29.130.10 ISBN 978-2-83220-615-7

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – TS 62271-210 © IEC:2013
CONTENTS

FOREWORD ........................................................................................................................... 4

1 General ............................................................................................................................ 6

1.1 Scope ...................................................................................................................... 6

1.2 Normative references .............................................................................................. 6

2 Normal and special service conditions .............................................................................. 7

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

4 Seismic qualification requirements ................................................................................... 7

4.1 General ................................................................................................................... 7

4.2 Preliminary analysis ................................................................................................ 7

4.2.1 Selection of the representative test sample ................................................. 7

4.2.2 Mathematical model of the test sample ........................................................ 7

4.3 Severities ................................................................................................................ 8

4.3.1 General ....................................................................................................... 8

4.3.2 Severity level 1 ............................................................................................ 8

4.3.3 Severity level 2 ............................................................................................ 9

4.4 Acceptance classes ............................................................................................... 10

5 Qualification by test ........................................................................................................ 10

5.1 General ................................................................................................................. 10

5.2 Mounting ............................................................................................................... 10

5.3 Test parameters .................................................................................................... 11

5.3.1 Measurements ........................................................................................... 11

5.3.2 Frequency range ....................................................................................... 11

5.3.3 Parameters for resonant frequency search ................................................ 11

5.3.4 Parameters for time history test (seismic load test) .................................... 11

5.4 Testing procedure ................................................................................................. 12

5.4.1 General ..................................................................................................... 12

5.4.2 Inspection and functional checks ............................................................... 12

5.4.3 Resonant frequency search ....................................................................... 12

5.4.4 Time history test (seismic load test) ........................................................... 12

6 Qualification by combination of test and analysis ............................................................ 13

6.1 General ................................................................................................................. 13

6.2 Numerical analysis ................................................................................................ 14

6.2.1 General ..................................................................................................... 14

6.2.2 Static data (stiffness) ................................................................................. 14

6.2.3 Dynamic data ............................................................................................ 14

6.2.4 Numerical model ........................................................................................ 14

6.2.5 Computation methods ................................................................................ 15

6.3 Analysis by experience or similarity ....................................................................... 16

7 Evaluation of the seismic qualification ............................................................................ 16

7.1 Validity criteria of the seismic test ......................................................................... 16

7.2 Acceptance criteria of the test results .................................................................... 16

7.3 Criteria of model acceptance ................................................................................. 17

7.4 Acceptance criteria of the numerical analysis results ............................................. 17

7.5 Acceptance criteria of the analysis results by similarity ......................................... 17

8 Documentation ............................................................................................................... 17

8.1 Information for seismic qualification ....................................................................... 17

---------------------- Page: 4 ----------------------
TS 62271-210 © IEC:2013 – 3 –

8.2 Test report ............................................................................................................ 17

8.3 Analysis report when analysis is a numerical analysis ........................................... 18

8.4 Analysis report when analysis is performed by similarity ........................................ 18

Annex A (normative) Characterization of the test sample for analysis .................................. 20

Annex B (informative) Criteria for seismic adequacy of enclosed switchgear and

controlgear assemblies ......................................................................................................... 21

Annex C (informative) Dynamic analysis methods ................................................................ 24

Annex D (informative) Expected peak ground accelerations for different earthquake

scales ................................................................................................................................... 27

Annex E (informative) Qualification process flowchart .......................................................... 28

Bibliography .......................................................................................................................... 29

Figure 1 – Severity level 1 (horizontal) – Zero period acceleration (ZPA) = 0,5 g .................... 9

Figure 2 – Severity level 2 (horizontal) − Zero period acceleration (ZPA) = 1 g ..................... 10

Table D.1 – Earthquake zones with earthquake intensity and magnitude scale ..................... 27

---------------------- Page: 5 ----------------------
– 4 – TS 62271-210 © IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
______________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
Part 210: Seismic qualification for metal enclosed and
solid-insulation enclosed switchgear and controlgear assemblies
for rated voltages above 1 kV and up to and including 52 kV
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

The main task of IEC technical committees is to prepare International Standards. In

exceptional circumstances, a technical committee may propose the publication of a technical

specification when

• the required support cannot be obtained for the publication of an International Standard,

despite repeated efforts, or

• the subject is still under technical development or where, for any other reason, there is the

future but no immediate possibility of an agreement on an International Standard.

Technical specifications are subject to review within three years of publication to decide

whether they can be transformed into International Standards.

IEC 62271-210, which is a technical specification, has been prepared by subcommittee 17C:

High-voltage switchgear and controlgear assemblies, of IEC technical committee 17:

Switchgear and controlgear.
---------------------- Page: 6 ----------------------
TS 62271-210 © IEC:2013 – 5 –
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
17C/515/DTS 17C/548/RVC

Full information on the voting for the approval of this technical specification can be found in

the report on voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all the parts in the IEC 62271 series, under the general title High-voltage switchgear

and controlgear, can be found on the IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 7 ----------------------
– 6 – TS 62271-210 © IEC:2013
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
Part 210: Seismic qualification for metal enclosed and
solid-insulation enclosed switchgear and controlgear assemblies
for rated voltages above 1 kV and up to and including 52 kV
1 General
1.1 Scope

This part of IEC 62271 applies to metal enclosed switchgear and controlgear assemblies

complying with IEC 62271-200 for metal enclosed and IEC 62271-201 for solid-insulation

enclosed, ground or floor mounted, intended to be used under seismic conditions.

The seismic qualification of the switchgear and controlgear assemblies takes into account any

auxiliary and the control equipment mounted directly on the assembly.

It will specify seismic severity levels, acceptance levels, and give a choice of methods that

may be applied to demonstrate the performance of high-voltage switchgear and controlgear

assemblies for which seismic qualification is required.

The seismic qualification of the switchgear and controlgear assemblies is only performed

upon request.
1.2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and

are indispensable for its application. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any
amendments) applies.

IEC 60068-2-6, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)

IEC 60068-2-57:1999, Environmental testing – Part 2-57: Tests – Test Ff: Vibration – Time-

history method

IEC 60068-2-64, Environmental testing – Part 2-64: Tests – Test Fh: Vibration, broadband

random and guidance

IEC 60068-3-3:1991, Environmental testing – Part 3: Guidance – Seismic test methods for

equipment

IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications

IEC 62271-200, High-voltage switchgear and controlgear – Part 200: AC metal-enclosed

switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV

IEC 62271-201, High-voltage switchgear and controlgear – Part 201: AC insulation-enclosed

switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV

ISO 2041, Mechanical vibration, shock and condition monitoring – Vocabulary
---------------------- Page: 8 ----------------------
TS 62271-210 © IEC:2013 – 7 –
2 Normal and special service conditions
(void)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60068-3-3,

IEC 62271-1, IEC 62271-200, IEC 62271-201 and ISO 2041 apply.
4 Seismic qualification requirements
4.1 General

The seismic qualification shall demonstrate the ability of the switchgear and controlgear

assemblies to withstand seismic stresses.

Basis of seismic qualification is the test, because only that allows a verification of functionality

of the equipment during and after the seismic events. The test is also a necessary input for

setup of numerical model used for analysis.
A combination of test and analysis is needed because not each type of switchgear
arrangement can be tested.
4.2 Preliminary analysis
4.2.1 Selection of the representative test sample

Due to practical reasons concerned with the available experimental facilities, the seismic

qualification of switchgear and controlgear assemblies requires the choice of proper test

samples which reasonably represent the whole system for the purpose of structural and

functional checks.

Such test samples shall include the switching devices with their relevant operating mechanism

and control equipment, and their electrical and mechanical interfaces.

These test samples shall demonstrate the worst cases, such as those with heaviest mass and

highest centre of gravity. In case of functional units with different masses, the heaviest panel

shall be placed at one end of the test arrangement. Simulation can be used to determine the

test sample, which satisfies the above criteria.
4.2.2 Mathematical model of the test sample

If qualification by combined test and numerical analysis, according to Clause 6, is foreseen, a

three-dimensional mathematical model of the test sample shall be created on the basis of

technical information concerning the design characteristics.

Such a model shall take into consideration the presence of switching and control devices,

compartments and of their supporting structures, and shall have sufficient sensitivity to

describe the dynamic behaviour of the test sample in the frequency range being studied.

The validity of the model shall be established by comparison between simulation results and

actual tests results, as stated in 7.3.
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– 8 – TS 62271-210 © IEC:2013
4.3 Severities
4.3.1 General
In earthquake zone 4 (risk of very strong earthquakes) the measured peak ground

acceleration in many cases is approximately 0,5 g. In a few cases the measured peak ground

acceleration is around 1 g (see also Annex D).

Due to the wide range of ground motions, site conditions, switchgear installations in buildings,

two severity levels are defined for seismic qualification in order to avoid designing or testing

always to the highest levels.

The shape of the Required Response Spectra (RRS) (severity levels 1 and 2) is a broadband

response spectrum to cover many site conditions (magnitude, depth and distance to epicentre,

rock or soft soil) and super elevation due to the floor level installation.
For qualification, one of the following severity levels shall be chosen:

The severity level 1 is recommended for peak ground / floor accelerations up to 0,5 g.

The severity level 2 is recommended for peak ground / floor accelerations up to 1,0 g.

The Required Response Spectra are given in Figures 1 and 2 for the different seismic

qualification levels. The curves relate to 2 %, 5 % and 10 % damping ratio of the switchgear

and controlgear assemblies. For testing and if the exact damping behaviour is unknown 5 %

damping ratio is recommended.

Severity Level 1 is recommended for equipments mounted at the ground level for zones 0 to 4

or at upper floor levels combined with earthquake zones 0 to 3 (see Annex D). For Zone 0, it

is not necessary to perform any seismic qualification.

Severity Level 2 is only recommended for equipments mounted at upper floor levels combined

with earthquake zone 4 (see Annex D).

If site-specific conditions are known the user may develop a site-specific response spectrum

which envelops the shape of the severity level 1 and/or severity level 2.

NOTE The severity level 1 is equivalent to the moderate performance level according to IEEE 693:2005.

The severity level 2 is equivalent to the high performance level according to IEEE 693:2005.

4.3.2 Severity level 1
The RRS is described by the following equations:
Horizontal spectral accelerations S (m/s²) for frequencies f (Hz):
• S = 1,144 × β × f × g for 0,0 ≤ f ≤ 1,1
• S = 1,250 × β × g for 1,1 ≤ f ≤ 8,0
• S = 2 × ((6,62 × β – 2,64) / f – 0,2 × β + 0,33)) × g for 8,0 ≤ f ≤ 33
• S = 0,5 × g for f ≥ 33

β = (3,21 – 0,68 ln (d)) / 2,115 6, where d is the percent damping (2, 5, 10 etc.) and d ≤ 20 %.

g = 10 m/s

For qualification the RRS is limited to a frequency range starting at 1,0 Hz (see 5.3.2).

---------------------- Page: 10 ----------------------
TS 62271-210 © IEC:2013 – 9 –
For vertical spectral accelerations the conversion factor is 0,8.

NOTE The conversion factor is 0,8 in order to harmonize the values settle by IEEE and IEC standards.

Severity Level 1 (hor.):
RRS (hor.) ZPA 0.5g d= 2% (level 1)
RRS (hor.) ZPA 0.5g d= 5% (level 1)
RRS (hor.) ZPA 0.5g d=10% (level 1)
1 10 100
Frequency [Hz]
IEC 245/13

SOURCE: Reproduced from IEEE Std 693:2005, IEEE Recommended Practice For Seismic Design of Substations

with the permission of IEEE.

Figure 1 – Severity level 1 (horizontal) – Zero period acceleration (ZPA) = 0,5 g

4.3.3 Severity level 2
The RRS is described by the following equations:
Horizontal spectral accelerations S (m/s²) for frequencies f (Hz):
• S = 2,288 × β × f × g for 0,0 ≤ f ≤ 1,1
• S = 2,5 × β × g for 1,1 ≤ f ≤ 8,0
• S = 2 × ((13,2 × β – 5,28)/ f – 0,4 × β+0,66)) × g for 8,0 ≤ f ≤ 33
• S = 1 × g for f ≥ 33

β = (3,21 – 0,68 ln (d)) / 2,115 6, where d is the percent damping (2, 5, 10 etc.) and d ≤ 20 %.

g = 10 m/s

For qualification the RRS is limited to a frequency range starting at 1,0 Hz (see 5.3.2).

For vertical spectral accelerations the conversion factor is 0,8.

NOTE The conversion factor is 0,8 in order to harmonize the values settle by IEEE and IEC standards.

Horizontal Acceleration
[m/s ]
---------------------- Page: 11 ----------------------
– 10 – TS 62271-210 © IEC:2013
Severity Level 2 (hor.):
RRS (hor.) ZPA 1g d= 2% (level 2)
RRS (hor.) ZPA 1g d= 5% (level 2)
RRS (hor.) ZPA 1g d=10% (level 2)
1 10 100
Frequency [Hz]
IEC 246/13

SOURCE: Reproduced from IEEE Std 693:2005, IEEE Recommended Practice For Seismic Design of Substations

with the permission of IEEE.
Figure 2 – Severity level 2 (horizontal) − Zero period acceleration (ZPA) = 1 g
4.4 Acceptance classes
Two acceptance classes for equipment are defined:

For class 1, the equipment has to maintain its functionality during and after the earthquake.

After the seismic event maintenance and partial replacement might be necessary to ensure

long term operation.

For class 2, the equipment has to maintain its functionality during and after the earthquake.

After the seismic event no maintenance is required.
5 Qualification by test
5.1 General

The test procedure shall be in accordance with IEC 60068-3-3 with the modification that the

time history test method in accordance with IEC 60068-2-57 shall be applied. The time history

test method more closely simulates actual conditions, because the behaviour of the test

sample is always not linear.

The seismic test should demonstrate the ability of the switchgear and controlgear assemblies

to perform its required functions during and after seismic loads in form of Test Response

Spectrum (TRS) that envelopes the RRS. The demonstration shall be performed as it is

settled in 5.4.1 and 5.4.3.

If a test sample cannot be tested with its supporting structure (e.g., due to its size), the

dynamic contribution of the structure shall be determined by analysis and accounted for in the

test.
5.2 Mounting

The test sample shall be mounted as in service condition including dampers (if any).

Horizontal Acceleration
[m/s ]
---------------------- Page: 12 ----------------------
TS 62271-210 © IEC:2013 – 11 –

If exact service conditions are unknown, a rigid base frame shall be used between the

equipment and the shaking table.

The horizontal orientation of the test sample shall be in the direction of excitation acting along

its two main orthogonal axes.
Any fixtures or connections req
...