High-voltage switchgear and controlgear - Part 4: Handling procedures for sulphur hexafluoride (SF<sub>6</sub>) and its mixtures

IEC 62271-4:2013 applies to the procedures for handling of SF6 during installation, commissioning, normal and abnormal operations, disposal at the end of life of high voltage switchgear and controlgear. This first edition cancels and replaces the first edition of IEC/TR 62271-303 published in 2008. This first edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) the description of the potential effects on health of SF6 by products (former Annex D of IEC/TR 62271-303:2008) has been replaced by the calculation methods for evaluating of the potential effects on health of SF6 by products (see Annex H);
b) information about cryogenic reclaim of SF6. Have been added (see Annex I);
c) handling procedures for the most popular SF6 mixtures have been added (see Annex J).

Appareillage à haute tension - Partie 4: Utilisation et manipulation de l'hexafluorure de soufre (SF<sub>6</sub>) et des mélanges contenant du SF<sub>6</sub>

La CEI 62271-4:2013 s'applique aux procédures de manipulation du SF6 lors de l'installation, de la mise en service, du fonctionnement normal ou anormal, et de l'élimination en fin de vie de l'appareillage à haute tension. Cette première édition annule et remplace la première édition de la CEI/TR 62271-303 parue en 2008. Cette première édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) remplacement de la description des effets potentiels sur la santé des produits de décomposition du SF6 (anciennement Annexe D de la CEI/TR 62271-303:2008) par les méthodes de calcul pour évaluer les effets potentiels sur la santé des produits de décomposition du SF6 (voir Annexe H);
b) ajout d'informations concernant la régénération cryogénique du SF6 (voir Annexe I);
c) ajout de procédures de manipulation pour les mélanges contenant du SF6 les plus courants (voir Annexe J).

General Information

Status
Published
Publication Date
25-Aug-2013
Technical Committee
Current Stage
PPUB - Publication issued
Start Date
26-Aug-2013
Completion Date
26-Aug-2013
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IEC 62271-4
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
High-voltage switchgear and controlgear –
Part 4: Handling procedures for sulphur hexafluoride (SF ) and its mixtures
Appareillage à haute tension –
Partie 4: Utilisation et manipulation de l'hexafluorure de soufre (SF ) et des
mélanges contenant du SF
IEC 62271-4:2013
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62271-4
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
High-voltage switchgear and controlgear –
Part 4: Handling procedures for sulphur hexafluoride (SF ) and its mixtures
Appareillage à haute tension –
Partie 4: Utilisation et manipulation de l'hexafluorure de soufre (SF ) et des
mélanges contenant du SF
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XC
ICS 29.130.10; 29.130.99 ISBN 978-2-8322-1042-0

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 – 62271-4 © IEC:2013
CONTENTS

FOREWORD ........................................................................................................................... 5

INTRODUCTION ..................................................................................................................... 7

1 General ............................................................................................................................ 8

1.1 Scope ...................................................................................................................... 8

1.2 Normative references .............................................................................................. 8

2 Terms and definitions ....................................................................................................... 9

3 SF handling during installation and commissioning ....................................................... 11

3.1 General ................................................................................................................. 11

3.2 Evacuation, filling and checking the SF quality after filling ................................... 11

3.3 Topping-up of SF pre-filled compartments to the rated filling

pressure/density .................................................................................................... 13

3.4 Filling sealed pressure systems ............................................................................. 15

4 SF handling during normal service life .......................................................................... 15

4.1 Re-filling of SF to the rated filling pressure/density .............................................. 15

4.2 Checking the SF quality ....................................................................................... 16

4.2.1 General ..................................................................................................... 16

4.2.2 Measurement of the SF quality with portable equipment .......................... 16

4.2.3 Sampling and shipment of SF for off-site analysis .................................... 17

5 SF recovery and reclaim during maintenance ............................................................... 18

5.1 General ................................................................................................................. 18

5.2 SF recovery and reclaim from any compartment of controlled or closed

pressure systems containing non-arced or normally arced SF ............................. 18

5.3 Recovery and reclaim from any compartment of controlled or closed

pressure systems containing heavily arced SF .................................................... 20

6 Dismantling of SF electric power equipment at the end-of-life ....................................... 22

6.1 General ................................................................................................................. 22

6.2 End-of-life of controlled or closed pressure systems .............................................. 23

6.3 End-of-life of sealed pressure systems .................................................................. 23

6.4 SF recovery and reclaim at the end-of-life of sealed pressure systems ................ 24

6.5 Dismantling of electric power equipment at the end-of-life ..................................... 26

6.6 By-products at the end-of-life ................................................................................ 27

Annex A (informative) Storage and transportation of SF ..................................................... 29

Annex B (informative) Safety and first aid ............................................................................ 33

Annex C (informative) Training and certification ................................................................... 39

Annex D (informative) Description of SF Handling Equipment ............................................ 43

Annex E (informative) Sulphur hexafluoride ......................................................................... 51

Annex F (informative) Environmental effects of SF ............................................................. 55

Annex G (informative) SF by-products................................................................................ 58

Annex H (informative) Procedure for evaluating the potential effects on health of SF

by-products ........................................................................................................................... 61

Annex I (informative) Cryogenic reclaim of SF ................................................................... 67

Annex J (normative) Handling of SF mixtures ..................................................................... 71

Bibliography .......................................................................................................................... 76

Figure 1 – Evacuation, filling and checking the SF quality after filling .................................. 12

---------------------- Page: 4 ----------------------
62271-4 © IEC:2013 – 3 –
Figure 2 – Topping-up of SF pre-filled compartments to the rated filling

pressure/density ................................................................................................................... 14

Figure 3 – SF re-filling to the rated filling pressure/density .................................................. 15

Figure 4 – Checking the SF quality on-site .......................................................................... 17

Figure 5 – SF sampling and shipment ................................................................................. 18

Figure 6 – Example of recovery and reclaim from any compartment of controlled or

closed pressure systems containing non-arced or normally arced SF .................................. 19

Figure 7 – Example of recovery and reclaim from any compartment of controlled or

closed pressure systems containing heavily arced SF ......................................................... 21

Figure 8 – End-of-life of controlled or closed pressure systems ............................................. 23

Figure 9 – End-of-life of sealed pressure systems ................................................................. 24

Figure 10 – SF recovery and reclaim at the end-of-life of sealed pressure systems ............. 25

Figure 11 – Dismantling of electric power equipment ............................................................ 27

Figure D.1 – General purpose reclaimer ............................................................................... 43

Figure D.2 – Gas mixing device ............................................................................................ 49

Figure E.1 – Pressure/temperature/density characteristics for SF [16] ................................ 52

Figure H.1 – Procedure for the evaluation of the potential effects on health due to

arcing ................................................................................................................................... 65

Figure H.2 – Procedure for the evaluation of the potential effects on health due to low

energy discharges ................................................................................................................ 66

Figure I.1 – Saturated vapour pressure of various gases as a function of temperature .......... 68

Figure I.2 – Typical cryogenic reclaimer for SF recovery on site .......................................... 69

Figure I.3 – Typical cryogenic reclaimer for removing contaminants ...................................... 70

Figure J.1 – Vapour pressure of SF ..................................................................................... 74

Figure J.2 – Maximum SF storage density to avoid SF liquefaction ................................... 75

6 6

Table 1 – Evacuation, filling and checking the SF quality after filling ................................... 13

Table 2 – Topping-up of SF pre-filled compartments to the rated filling

pressure/density. .................................................................................................................. 14

Table 3 – SF re-filling to the rated filling pressure/density ................................................... 16

Table 4 – Checking the SF quality on-site ........................................................................... 17

Table 5 – SF sampling and shipment .................................................................................. 18

Table 6 – Example of recovery and reclaim from any compartment of controlled or

closed pressure systems containing non-arced or normally arced SF .................................. 20

Table 7 – Example of recovery and reclaim from any compartment of controlled or

closed pressure systems containing heavily arced SF ......................................................... 22

Table 8 – SF recovery at the end-of-life of sealed pressure systems ................................... 26

Table 9 – Expected SF characteristics and quantity of by-products ..................................... 28

Table A.1 – Methods for storage of SF ................................................................................ 29

Table A.2 – Container types and labelling required for storage and transportation of

SF ....................................................................................................................................... 30

Table A.3 – International regulations for shipment of SF ..................................................... 31

Table B.1 – Measures when working with SF electric power equipment............................... 33

Table B.2 – Safety measures when opening or accessing gas compartments ........................ 34

Table B.3 – Neutralising solutions ......................................................................................... 35

Table B.4 – Additional safety measures ................................................................................ 37

---------------------- Page: 5 ----------------------
– 4 – 62271-4 © IEC:2013

Table D.1 – Typical filter types used during SF reclaim ....................................................... 44

Table D.2 – Gas measuring devices ...................................................................................... 47

Table E.1 – Main chemical characteristics of SF [16] .......................................................... 51

Table E.2 – Main physical characteristics of SF [16] ........................................................... 53

Table E.3 – Main electrical characteristics of SF [16] .......................................................... 53

Table H.1 – OELs for SO , HF, and S F ........................................................................... 63

2 2 10

Table H.2 – SOF production rate ......................................................................................... 63

---------------------- Page: 6 ----------------------
62271-4 © IEC:2013 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
Part 4: Handling procedures for sulphur hexafluoride (SF )
and its mixtures
FOREWORD

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

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

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

International Standard IEC 62271-4 has been prepared by subcommittee 17A: High-voltage

switchgear and controlgear, of IEC technical committee 17: Switchgear and controlgear.

This first edition cancels and replaces the first edition of IEC/TR 62271-303 published in

2008.

This first edition constitutes a technical revision. This edition includes the following significant

technical changes with respect to the previous edition:

a) the description of the potential effects on health of SF by-products (former Annex D of

IEC/TR 62271-303:2008) has been replaced by the calculation methods for evaluating of

the potential effects on health of SF by-products (see Annex H);
b) information about cryogenic reclaim of SF .have been added (see Annex I);

c) handling procedures for the most popular SF mixtures have been added (see Annex J).

---------------------- Page: 7 ----------------------
– 6 – 62271-4 © IEC:2013
The text of this standard is based on the following documents:
FDIS Report on voting
17A/1044/FDIS 17A/1051/RVD

Full information on the voting for the approval of this standard 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 parts in the IEC 62271, published 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
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
---------------------- Page: 8 ----------------------
62271-4 © IEC:2013 – 7 –
INTRODUCTION

As agreed with TC 10, annexes A, E, F, G, H and I will be removed from this document as

soon as the revised editions of IEC 60376 and IEC 60480 have been published.
---------------------- Page: 9 ----------------------
– 8 – 62271-4 © IEC:2013
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
Part 4: Handling procedures for sulphur hexafluoride (SF )
and its mixtures
1 General
1.1 Scope

This part of IEC 62271 applies to the procedures for handling of SF during installation,

commissioning, normal and abnormal operations, disposal at the end-of-life of high-voltage

switchgear and controlgear.

These procedures are regarded as minimum requirements to ensure the safety of personnel

working with SF (see Annex B) and to minimize the SF emission to the environment.

6 6

This standard generally applies also to gas mixtures containing SF . The particularities for

their handling are covered in Annex J.

NOTE 1 Throughout this standard, use of the term High-Voltage (refer to IEC 60050-601:1985, 601-01-27) means

a rated voltage above 1 000 V. However the term Medium Voltage (refer to IEC 60050-601: 1985, 601-01-28) is

commonly used for distribution systems with voltages above 1 kV and generally applied up to and including 52 kV.

NOTE 2 Throughout this standard, the term “electric power equipment” stands for “high-voltage and

medium-voltage switchgear and controlgear”.

NOTE 3 Throughout this standard, the term “pressure” stands for “absolute pressure”.

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 60050-441, International Electrotechnical Vocabulary – Chapter 441: Switchgear,

controlgear and fuses

IEC 60050-601, International Electrotechnical Vocabulary – Chapter 601: Generation,

transmission and distribution of electricity – General

IEC 60376, Specification of technical grade sulphur hexafluoride (SF ) for use in electrical

equipment

IEC 60480, Guidelines for the checking and treatment of sulphur hexafluoride (SF ) taken

from electrical equipment and specifications for its re-use

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

EN 1089-3, Transportable gas cylinders. Gas cylinder identification (excluding LPG). Colour

coding
---------------------- Page: 10 ----------------------
62271-4 © IEC:2013 – 9 –
2 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60050-441 and

IEC 60050-601, as well as the following apply.
2.1
abnormal release of SF

release from equipment in service due to a failure in the pressure system or mistake in the

handling process

Note 1 to entry: An abnormal SF leak is usually an unwanted and continuous emission of gas at a higher rate

than the equipment designed leak rate. As soon as an abnormal SF leak is detected, appropriate measures to

locate and eliminate it should be arranged.
2.2
handling of SF
any process which might involve transfer of SF
2.3
evacuation

transfer of a gas different from SF (e.g. air or N ) which can be released into the

6 2
atmosphere. The operation is performed utilising a vacuum pump
2.4
recovery of SF
transfer of SF from the gas compartment into a reclaimer or storage container

Note 1 to entry: The operation is normally performed utilising a recovery compressor.

2.5
topping-up with SF
filling a pre-filled compartment with SF to the rated filling pressure

Note 1 to entry: Pre-filled compartments are closed pressure systems filled in the factory prior to shipment. They

contain SF at a typical pressure between 0,12 MPa to 0,15 MPa allowing for a faster and easier commissioning

on-site.
2.6
re-filling with SF
to the rated filling pressure to assure continuity of service
filling a compartment with SF
2.7
reclaim of SF

a series of SF handling procedures including recovery and minimum SF refining process

6 6
such as filtering dust, by-products, moisture, oil, etc.

Note 1 to entry: A standard reclaimer is described in Annex D; while a cryogenic reclaimer is described in

Annex I.

Note 2 to entry: Sometimes the words “reclaiming” or “reclamation” may be used with the same meaning as

“reclaim”.
2.8
gas-insulated metal-enclosed switchgear

metal-enclosed switchgear in which the insulation is obtained, at least partly, by an insulating

gas other than air at atmospheric pressure

Note 1 to entry: This term generally applies to high-voltage switchgear and controlgear.

[SOURCE: IEC 60050-441: 1984, 441-12-05]
---------------------- Page: 11 ----------------------
– 10 – 62271-4 © IEC:2013
2.9
gas-filled compartment

compartment of switchgear and controlgear in which the gas pressure is maintained by one of

the following systems:
• controlled pressure system;
• closed pressure system;
• sealed pressure system

Note 1 to entry: Several gas-filled compartments may be permanently interconnected to form a common gas-

system (gas-tight assembly).
Note 2 to entry: The definition is the same as in IEC 62271-1.
2.10
controlled pressure system for gas

volume which is automatically replenished from an external compressed gas supply or internal

gas source

Note 1 to entry: Examples of controlled pressure systems are air-blast circuit-breakers or pneumatic operating

mechanisms.

Note 2 to entry: A volume may consist of several permanently connected gas-filled compartments.

Note 3 to entry: The definition is the same as in IEC 62271-1.
2.11
closed pressure system for gas

volume which is replenished only periodically by manual connection to an external gas source

Note 1 to entry: Example of closed pressure systems are SF single pressure circuit-breakers.

Note 2 to entry: The definition is the same as in IEC 62271-1.
2.12
sealed pressure system

volume for which no further gas or vacuum processing is required during its expected

operating life

Note 1 to entry: Examples of sealed pressure systems are tubes of vacuum circuit-breakers or some SF

circuit-breakers.

Note 2 to entry: Sealed pressure systems are completely assembled and tested in the factory.

Note 3 to entry: The definition is the same as in IEC 62271-1.
2.13
technical grade SF
SF gas having a very low level of impurities in accordance with IEC 60376
2.14
used SF

gas removed from an item of electrical equipment, initially filled with SF according to

IEC 60376 or IEC 60480

Note 1 to entry: If after filling, the gas is removed for any purpose during the life of the equipment, e.g. repair,

service, maintenance, the gas will be transferred and is considered as used gas.

Note 2 to entry: Annex G provides information regarding the by-products of used SF , which occur in both

gaseous and solid form.
2.15
used SF suitable for reuse on site
used SF having a maximum impurity level in accordance with IEC 60480
---------------------- Page: 12 ----------------------
62271-4 © IEC:2013 – 11 –

Note 1 to entry: If necessary, service units with appropriate filters and adsorber materials should be used.

2.16
suitable for reuse at the gas manufacturer
...

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