High-voltage fuses - Part 4: Additional testing requirements for high-voltage expulsion fuses utilizing polymeric insulators

IEC 60282-4:2020 applies to expulsion fuses complying with IEC 60282-2 and specifies additional testing requirements for fuses employing a cutout fuse-base that utilizes polymeric insulators.

Fusibles à haute tension - Partie 4: Exigences d'essai supplémentaires pour les fusibles à expulsion à haute tension utilisant des isolateurs polymériques

IEC 60282-4:2020 s'applique aux fusibles à expulsion conformes à l'IEC 60282.­2 et spécifie les exigences d'essai supplémentaires pour les fusibles qui comprennent un socle de déconnecteur à isolateurs polymériques.

General Information

Status
Published
Publication Date
15-Apr-2020
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
16-Apr-2020
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IEC 60282-4
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage fuses –

Part 4: Additional testing requirements for high-voltage expulsion fuses utilizing

polymeric insulators
Fusibles à haute tension –
Partie 4: Exigences d'essai supplémentaires pour les fusibles à expulsion à
haute tension utilisant des isolateurs polymériques
IEC 60282-4:2020-04(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60282-4
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage fuses –

Part 4: Additional testing requirements for high-voltage expulsion fuses utilizing

polymeric insulators
Fusibles à haute tension –
Partie 4: Exigences d'essai supplémentaires pour les fusibles à expulsion à
haute tension utilisant des isolateurs polymériques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-8089-8

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 – IEC 60282-4:2020 © IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

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

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

3 Terms and definitions ...................................................................................................... 6

4 Type tests ....................................................................................................................... 8

4.1 General requirements ............................................................................................. 8

4.2 Mechanical tests ..................................................................................................... 8

4.2.1 Mechanical stressing at temperature extremes ................................................ 8

4.2.2 Long term deformation/creep testing .............................................................. 10

4.3 Environmental tests .............................................................................................. 11

4.3.1 General ......................................................................................................... 11

4.3.2 Accelerated weathering test ........................................................................... 11

4.3.3 Tracking and erosion test .............................................................................. 12

4.3.4 Flammability test ........................................................................................... 13

4.4 Tests on interfaces and connections of end fittings ............................................... 13

4.4.1 General ......................................................................................................... 13

4.4.2 Water immersion pre-stressing procedure ...................................................... 14

4.4.3 Verification tests ............................................................................................ 14

4.5 Breaking tests with dye penetration....................................................................... 15

4.5.1 General ......................................................................................................... 15

4.5.2 Description of tests to be made ..................................................................... 15

4.6 Acceptance criteria ............................................................................................... 15

Bibliography .......................................................................................................................... 16

Figure 1 – Test sequence ....................................................................................................... 9

Figure 2 – Dye penetration test arrangement ........................................................................ 10

Figure 3 – Tracking wheel test arrangement ......................................................................... 13

---------------------- Page: 4 ----------------------
IEC 60282-4:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HIGH-VOLTAGE FUSES –
Part 4: Additional testing requirements for high-voltage
expulsion fuses utilizing polymeric insulators
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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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60282-4 has been prepared by subcommittee 32A: High-voltage

fuses, of IEC technical committee 32: Fuses.
The text of this International Standard is based on the following documents:
FDIS Report on voting
32A/346/FDIS 32A/348/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

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

---------------------- Page: 5 ----------------------
– 4 – IEC 60282-4:2020 © IEC 2020

A list of all parts in the IEC 60282 series, published under the general title High-voltage fuses,

can be found on the IEC website.

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

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 6 ----------------------
IEC 60282-4:2020 © IEC 2020 – 5 –
INTRODUCTION

High-voltage expulsion fuses are tested according to IEC 60282-2 which recognizes that fuse-

bases may use polymer (non-ceramic) insulators. However, very little additional testing is

specified for fuses using such insulators. In the case of polymer post insulators and

suspension insulators, only artificial pollution tests are required in accordance with IEC 61592

and IEC 61109, respectively. However, for fuses that use insulators not covered by these

International Standards, such as certain fuse-cutouts, the additional testing required is by

agreement between manufacturer and user. Fuses that need such "additional testing" are

expulsion fuses that utilize polymer insulators in which a single mounting bracket is used,

either at the centre of an insulator or connected to two insulators (a "cutout fuse-base"). As

the market for expulsion fuses using polymer insulators has grown, manufacturers have

introduced many tests in addition to artificial pollution tests, covering other aspects of a fuse's

performance. This document formalises such testing and provides standardisation and

consistency. It should be noted that the document focusses on product testing as opposed to

material testing. In addition to drawing on test procedures covered by IEC 62217:2012,

Polymeric HV insulators for indoor and outdoor use – General definitions, test methods and

acceptance criteria, material from IEEE Std C37.41™:2016 (primarily 18.1.2 Long-term

deformation/creep testing) is also used, with the permission of IEEE.
---------------------- Page: 7 ----------------------
– 6 – IEC 60282-4:2020 © IEC 2020
HIGH-VOLTAGE FUSES –
Part 4: Additional testing requirements for high-voltage
expulsion fuses utilizing polymeric insulators
1 Scope

This part of IEC 60282 applies to expulsion fuses complying with IEC 60282-2 and specifies

additional testing requirements for fuses employing a cutout fuse-base that utilizes polymeric

insulators.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their

content constitutes requirements 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.

IEC 60060-1:2010, High-voltage test techniques – Part 1: General definitions and test

requirements
IEC 60282-2:2008, High-voltage fuses – Part 2: Expulsion fuses

ISO 4287, Geometrical Product Specifications (GPS) – Surface Texture: Profile method –

Terms, definitions and surface texture parameters

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

lamps

ISO 868, Plastics and ebonite – Determination of indentation hardness by means of a

durometer (Shore hardness)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
polymeric insulator
insulator whose insulating body consists of at least one organic based material
Note 1 to entry: Polymeric insulators are also known as non-ceramic insulators.

Note 2 to entry: Coupling devices may be attached to the ends of the insulating body.

[SOURCE: IEC 60050-471:2007, 471-01-13]
---------------------- Page: 8 ----------------------
IEC 60282-4:2020 © IEC 2020 – 7 –
3.2
composite polymeric insulator

polymeric insulator made of at least two polymeric insulating parts, namely a core and a

housing equipped with end fittings

[SOURCE: IEC 60050-471:2007, 471-01-02, modified – the term "polymeric" added and the

note to entry deleted.]
3.3
core (of a composite polymeric insulator)

central insulating part of a composite polymeric insulator which provides the primary

mechanical characteristics of the insulator

[SOURCE: IEC 60050-471:2007, 471-01-03, modified – addition of "composite polymeric";

addition of "primary" and "of the insulator"; note to entry deleted.]
3.4
housing

external insulating part(s) of a composite polymeric insulator that provides the necessary

creepage distance, other dielectric characteristics of the insulator, and protects the core from

the environment

[SOURCE: IEC 60050-471:2007, 471-01-09, modified – "of a composite polymeric insulator"

and "other dielectric characteristics of the insulator" added.]
3.5
insulating body
insulating assembly that contains the insulator and permanent fittings
3.6
insulator trunk
central insulating part of an insulator from which the sheds project
Note 1 to entry: Also known as shank on smaller insulators.
[SOURCE: IEC 60050-471:2007, 471-01-11]
3.7
shed (of an insulator)

insulating part, projecting from the insulator trunk, intended to increase the creepage distance

Note 1 to entry: The shed can be with or without ribs.
[SOURCE: IEC 60050-471:2007, 471-01-15]
3.8
cutout fuse-base

fuse-base that uses an insulator or insulators having a single point mounting bracket

Note 1 to entry: The mounting bracket is generally located centrally between the terminals that are mounted at

the outer ends of the insulator(s).
3.9
resin insulator

polymeric insulator whose insulating body consists of a solid shank and sheds protruding from

the shank made from only one organic based housing material (e.g. cycloaliphatic epoxy)

---------------------- Page: 9 ----------------------
– 8 – IEC 60282-4:2020 © IEC 2020
3.10
interface
surface between the different materials

Note 1 to entry: Various interfaces occur in most composite insulators, for example:

– between housing and fixing devices;
– between core and housing.
4 Type tests
4.1 General requirements

Fuses according to this document shall comply with the requirements of IEC 60282-2, except

for those that are specifically replaced with requirements specified in this document for the

following type tests.
4.2 Mechanical tests
4.2.1 Mechanical stressing at temperature extremes
4.2.1.1 General

When conducting this test with a fuse using a polymeric insulator(s), it is not necessary to

perform the mechanical tests outlined in 8.8.1 of IEC 60282-2:2008. The testing covered

in 4.2.1 only applies to devices that can be opened and closed manually.
4.2.1.2 Test procedure

Three new fuses shall be used for this test. The test samples shall consist of the fuse-base,

fuse-carrier, and end fittings. The fuse carriers should contain fuse-links of sufficiently high

current rating, or dummy links, so that the fuse-links are not subjected to the same endurance

test as the fuse-bases and fuse-carriers.

All samples shall be cycled between −30 °C (+0 °C, −5 °C) and +40 °C (+5 °C, −0 °C). The

samples shall remain at each temperature extreme for a minimum of 8 h per cycle. The cycle

time from one temperature extreme to the other shall be any convenient value, however the

sample rate of temperature change should be no more than 0,5 °C/min to avoid thermal shock.

All samples shall complete 4 cycles (a cycle includes both temperature extremes) resulting in

a minimum total test time of approximately 83 h. See Figure 1 for a representation of the

preferred test sequence. If the specified minimum ambient air temperature for the fuse is

other than −30 °C (see IEC 60282-2:2008, 4.1 a)) then this value (+0 °C, −5 °C) shall be used

for the minimum temperature of the cycle.

Once per cycle, manual open/close operations shall be performed, using a device approved

by the manufacturer. At the end of an eight-hour cold or hot period, each sample is subjected

to 50 open/close operations. All operations shall be performed at a minimum 30° angle from

centreline with 25 on the right and 25 on the left. The closing force should simulate typical

service conditions as recommended by the manufacturer. Tests shall alternate with each

cycle such that over the four cycles, a total of 100 open/close operations are performed hot

and 100 open/close operations cold. The four-cycle sequence can start with a hot period or

cold period, but a cold period is the preferred sequence.
---------------------- Page: 10 ----------------------
IEC 60282-4:2020 © IEC 2020 – 9 –
Figure 1 – Test sequence
4.2.1.3 Acceptance criteria
4.2.1.3.1 Initial acceptance criteria
The following are the initial criteria for successful completion of this test:
a) Overall length of fuse-base shall comply with manufacturer's specification.

b) No loose or deformed parts, cracks or other obvious visual deformation in any of the

assemblies shall occur.
c) Each sample shall perform its intended function as demonstrated by 4.2.1.3.2.
4.2.1.3.2 Acceptance testing

After the samples have passed the initial acceptance criteria listed in 4.2.1.3.1, further tests

are performed to determine that the fuse has not received damage to impair its current

carrying capability and drop-out capability.

a) Each sample shall be subjected to a temperature rise test as specified in IEC 60282-2.

The temperature rise of individual components may exceed the temperature rise limits

specified in IEC 60282-2, provided that all temperature measurements demonstrate that

the fuse has reached temperature stability, without thermal runaway occurring.

b) Each sample shall demonstrate it is capable of full mechanical performance when a fuse

element melts. For drop-out devices, capability can be verified by the following process.

Each sample shall have a fuse-carrier mounted in the fuse-support with an appropriately

sized fuse-link. Sufficient current shall be passed through the fuse to cause the element to

melt. The sample shall operate and move to the proper open condition.
4.2.1.4 Dye penetration test for composite polymeric insulators

After the testing detailed in 4.2.1.3.1 and 4.2.1.3.2 a dye penetration test is performed to

verify that no damage to the core material occurred during the mechanical tests. Four

samples shall be cut from each tested insulator making the cut approximately 90° to the long

axis of the insulator. Using a diamond-coated circular saw blade under running cold water is

the preferred method, however other cutting methods may be used with agreement from the

manufacturer. The length of the samples shall be 10 mm ± 1,0 mm. The cut surfaces shall be

smoothed by means of fine abrasive cloth (grain size 180). The cut ends shall be clean and

parallel. The specimens shall be placed (long axis of the insulator vertical) on a layer of steel

or glass balls of the same diameter (1 mm to 2 mm) in a vessel or tray. A solution of 1 % (by

---------------------- Page: 11 ----------------------
– 10 – IEC 60282-4:2020 © IEC 2020

weight) of Astrazon BR 200 in methanol shall be poured into the vessel, its level being 2 mm

to 3 mm higher than the level of the balls. See Figure 2 for a representation of this test

arrangement. The specimens shall be observed for 15 min. Other, equivalent, products to

Astrazon BR 200 may be used.
Dimensions in millimetres
Figure 2 – Dye penetration test arrangement
4.2.1.5 Dye penetration test acceptance criteria

No dye shall rise through the specimens before the 15 min have elapsed. Steps may be taken

to prevent dye wicking up the outside surface of the samples.
4.2.2 Long term deformation/creep testing
4.2.2.1 General

This test is for fuses that incorporate composite and/or resin type polymeric insulators.

4.2.2.2 Number of devices to be tested

Three new test samples shall be used for this test, consisting of a fuse-base and a

disconnecting blade, or a fuse-base, fuse-carrier and fuse-link. The test procedure is:

a) The distance between the upper contact and lower hinge on all three fuse-bases shall be

measured.

b) The test samples shall be placed into an oven at 75 °C (+5 °C, −0 °C) until all components

have reached thermal equilibrium.

c) Once all components have reached the proper temperature, the three disconnecting

blades or fuse-carriers and fuse-links shall be installed into the three fuse-bases in the

closed position.

d) After 8 h have passed, the first device is removed and placed in a water bath, at ambient

temperature, for one minute. After one minute, the disconnecting blade or fuse-carrier and

fuse-link is removed and the distance between the upper contact and lower hinge is

measured.
_____________

Astrazon BR 200 is an example of a suitable product available commercially. This information is given for the

convenience of users of this document and does not constitute an endorsement by the IEC of this product.

Reproduced from IEEE Std C37.41:2016, with the permission of IEEE.
---------------------- Page: 12 ----------------------
IEC 60282-4:2020 © IEC 2020 – 11 –

e) After 24 h have passed, the second device is removed and placed in a water bath, at

ambient temperature, for one minute. After one minute, the disconnecting blade or fuse-

carrier and fuse-link is removed and the distance between the upper contact and lower

hinge is measured.

f) After 168 h, the final device is removed and placed in a water bath, at ambient

temperature, for one minute. After one minute, the disconnecting blade or fuse-carrier and

fuse-link is removed and the distance between the upper contact and lower hinge is

measured.
4.2.2.3 Acceptance criteria

a) The final measured length of all samples shall be within the limits defined by the

manufacturer.

b) Each sample shall be subjected to a temperature rise test at rated current of the fuse-base

or fuse-carrier, whichever is lower. The temperature rise of individual components may

exceed the temperature rise limits specified in IEC 60282-2, provided that all

measurements demonstrate that temperature stability, without thermal runaway, has

occurred.
c) The samples shall demonstrate that they remain capable of proper mechanical

performance. For dropout devices, performance shall be verified by the following process.

Each sample shall have a fuse-carrier mounted in the fuse-support and current passed

through the fuse element sufficient to melt it. The sample shall be verified to have

operated and moved to the proper open state.
4.3 Environmental tests
4.3.1 General

These tests are for fuses that incorporate composite and/or resin type polymeric insulators.

4.3.2 Accelerated weathering test
4.3.2.1 Test procedure

Three new fuse-bases shall be selected with labels/markings included, if applicable.

The new fuse-bases shall be subjected to a 1 000 h UV light test using the following test

method. Markings on the housing, if any, shall be directly exposed to UV light:
Xenon-arc methods: ISO 4892-2, using cycle 1 with a dark period of 8 h

NOTE More information on accelerated weathering tests can be found in CIGRE Technical Brochure No. 488.

4.3.2.2 Acceptance criteria

After the test, markings on shed or housing material shall still be legible; cracks, blisters, and

crumbling are not permitted. General surface degradation shall be measured using the

following method.

Two surface roughness measurements shall be made on each of the three specimens. The

roughness, Rz as defined in ISO 4287, shall be measured along a sampling length of at least

2,5 mm. Rz shall not exceed 0,1 mm.

A 1 min dry power frequency withstand voltage test shall be performed on each sample (fitted

with a disconnecting blade, or a fuse-carrier and fuse-link) as specified i
...

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