SIST HD 307.2.2 S1:1998

SLOVENSKI STANDARD
SIST HD 307.2.2 S1:1998
01-oktober-1998
Specification for solventless polymerisable resinous compounds used for
electrical insulation -- Part 2: Methods of test - Test methods for coating powders
for electrical purposes (IEC 60455-2-2:1984 + Corrigendum December 1991)
Specification for solventless polymerisable resinous compounds used for electrical
insulation -- Part 2: Methods of test -- Test methods for coating powders for electrical
purposes
Bestimmungen für Reaktionsharzmassen und -formstoffe in der Elektrotechnik -- Teil 2:
Prüfmethoden -- Prüfverfahren für Beschichtungspulver für elektronische Zwecke
Spécifications relatives aux composés résineux polymérisables sans solvent utilisés
comme isolants électriques -- Partie 2: Méthodes d'essai -- Méthodes d'essai des
poudres de revêtement à usages électriques
Ta slovenski standard je istoveten z: HD 307.2.2 S1:1986
ICS:
29.035.01 Izolacijski materiali na Insulating materials in
splošno general
SIST HD 307.2.2 S1:1998 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST HD 307.2.2 S1:1998

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SIST HD 307.2.2 S1:1998

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SIST HD 307.2.2 S1:1998

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SIST HD 307.2.2 S1:1998
NORME CEI
INTERNATIONALE IEC
60455-2-2
INTERNATIONAL
Première édition
STAN DARD
First edition
1984-01
Spécification relative aux composés résineux
polymérisables sans solvant utilisés comme
isolants électriques
Deuxième partie:
Méthodes d'essai — Méthodes d'essai des poudres
de revêtement à usages électriques
Specification for solventless polymerisable
resinous compounds used for electrical insulation
Part 2:
Methods of test — Test methods for coating
powders for electrical purposes
© IEC 1984 Droits de reproduction réservés — Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE
International Electrotechnical Commission
IEC
MeNinyHapoiariaR 3ne11rpoTexHN4ecna q HoMHCCHc
Pour prix, voir catalogue en vigueur
• •
For price, see current catalogue

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SIST HD 307.2.2 S1:1998
IEC Publication 455-2-2
Publication 455-2-2 de la CEI
(First edition - 1984)
(Première édition - 1984)
Spécification relative aux composés Specification for solventless
polymerisable resinous compounds
résineux polymérisables sans solvant
used for electrical insulation
utilisés comme isolants électriques
Part 2: Methods of test
Deuxième partie: Méthodes d’essai
Test methods for coating powders
Méthodes d’essai des de revêtement
poudres
for electrical purposes
à usages électriques
C O R R I G E N D U M 1
Page 4
Préface
Remplacer le tableau existant par le nouveau tableau suivant:
Règle des Six Mois Rapport de vote Procédure des Deux Mois Rapport de vote
15C(BC)139 15C(BC)161 15C(BC)165 15C(BC)190
Pour de plus amples renseignements, consulter les rapports de vote mentionnés dans le tableau ci-dessus.
Page 5
Preface
Replace the existing table by the following new table:
Six Months’ Rule Report on Voting Two Months’ Procedure Report on Voting
15C(CO)139 15C(CO)161 15C(CO)165 15C(CO)190
Further information can be found in the Reports on Voting indicated in the table above.
Août 1991 August 1991

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SIST HD 307.2.2 S1:1998

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SIST HD 307.2.2 S1:1998
455-2-2 © IEC 1984 — 3 —
CONTENTS
Page
FOREWORD 5
5
PREFACE
INTRODUCTION 9
Clause
Scope 9
SECTION ONE — TESTS FOR MATERIALS BEFORE CURE
1.1 Bulk density 9
Pourability 9
1.2
11
1.3 Particle size distribution
11
1.4 Softening temperature
11
1.5 Gel time
13
1.6 Non-volatile matter content
TWO — TESTS FOR MATERIALS IN THE CURED FORM
SECTION
15
2.1 Preparation of test specimens
15
2.2 Visual examination
15
2.3 Thickness
17
2.4 Porosity of coating (test for uniformity)
17
2.5 Scratch hardness
21
2.6 Cut-through resistance
21
2.7 Impact strength
23
2.8 Cupping test
23
2.9 Electric strength
25 2.10 Dissipation factor and permittivity
25
2.11 Volume resistivity after immersion in water
25
2.12 Resistance to tracking
27 2.13 Resistance to chemicals
29
2.14 Resistance to vapour of solvents
31
2.15 Thermal endurance
31
2.16 Edge coverage
33 2.17 Thermal shock resistance
35
FIGURES

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SIST HD 307.2.2 S1:1998
455-2-2 © I E C 1984 — 5 —
INTERNATIONAL ELECTROTECHNICAL COMMISSION
SPECIFICATION FOR
SOLVENTLESS POLYMERISABLE RESINOUS COMPOUNDS
USED FOR ELECTRICAL INSULATION
Part 2: Methods of test
Test methods for coating powders for electrical purposes
FOREWORD
1) The formal decisions or agreements of the I EC on technical matters, prepared by Technical Committees on which all the National
Committees having a special interest therein are represented, express, as nearly as possible, an inte rnational consensus of opinion
on the subjects dealt with.
2) They have the form of recommendations for inte rnational use and they are accepted by the National Committees in that
sense.
ational unification, the I EC expresses the wish that all National Committees should adopt the text of
3) In order to promote intern
the I EC recommendation for their national rules in so far as national conditions will permit. Any divergence between the I E C
recommendation and the corresponding national rules should, as far as possible, be clearly indicated in the latter.
PREFACE
This standard has been prepared by Sub-Committee 15C: Specifications, of I EC Technical Committee No. 15: Insulating
Materials.
The text of this standard is based upon the following documents:
Report on Voting
Six Months' Rule
15C(CO)139 15C(CO)161
Further information can be found in the Repo rt on Voting indicated in the table above.
The following IEC publications are quoted in this standard:
rt 7: Construction and Test of Elec-
Publications Nos. 79-7 (1969): Electrical Apparatus for Explosive Gas Atmospheres, Pa
trical Apparatus, Type of Protection "e".
93 (1980): Methods of Test for Volume Resistivity and Surface Resistivity of Solid Electrical Insulating
Materials.
112 (1979): Method for Determining the Comparative and the Proof Tracking Indices of Solid Insulating
Materials under Moist Conditions.
212 (1971): Standard Conditions for Use prior to and during the Testing of Solid Electrical Insulating
Materials.
216-1 (1974): Guide for the Determination of Thermal Endur ance Properties of Electrical Insulating Mate-
rials, Part 1: General Procedures for the Determination of Thermal Endurance Properties,
Temperature Indices and Thermal Endurance Profiles.
243 (1967): Recommended Methods of Test for Electric Strength of Solid Insulating Materials at Power
Frequencies.
250 (1969): Recommended Methods for the Determination of the Permittivity and Dielectric Dissipation
Factor of Electrical Insulating Materials at Power, Audio and Radio Frequencies including
Metre Wavelengths.
394-2 (1972): Varnished Fabrics for Electrical Purposes, Pa rt 2: Methods of Test.
455-1 (1974): Specification for Solventless Polymerisable Resinous Compounds Used for Electrical Insula-
tion, Part 1: Definitions and General Requirements.
455-2 (1977): Part 2: Methods of Test.

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SIST HD 307.2.2 S1:1998
455-2-2 © — 7
IEC 1984
Other publications quoted:
ISO Standard 60 (1977): Plastics — Determination of Apparant Density of Material that Can be Poured from a Speci-
fied Funnel.
683-1 (1968): Heat-treated Steels, Alloy Steels and Free-cutting Steels, Part 1: Quenched and Tempered
Unalloyed Steels.
1518 (1973): Paints and Varnishes — Scratch Test.
2591 (1973): Test Sieving.

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SIST HD 307.2.2 S1:1998
455-2-2 © IEC 1984 — 9
SPECIFICATION FOR
SOLVENTLESS POLYMERISABLE RESINOUS COMPOUNDS
USED IN ELECTRICAL INSULATION
Part 2: Methods of test
Test methods for coating powders for electrical purposes
INTRODUCTION
This standard is one of the series which deals with solventless polymerisable resinous compounds used
rts:
for electrical insulation. The series will have the following three pa
Part 1: Definitions and general requirements.
Part 2: Methods of test.
Part 3: Specifications for individual materials (under consideration).
Scope
This standard gives methods of test for thermo-setting coating powders as defined in Sub-
clause 3.7 of IEC Publication 455-1: Specification for Solventless Polymerisable Resinous
1: Definitions and General Requirements. Tests are
Compounds used for Electrical Insulation, Part
included for the material before cure and in the cured form.
SECTION ONE — TESTS FOR MATERIALS BEFORE CURE
1.1 Bulk density
To be determined in accordance with ISO Standard 60: Plastics — Determination of Apparent
Density of Material that Can be Poured from a Specified Funnel.
1.2
Pourability
1.2.1 Apparatus
Funnel according to Figure 1, page 35, provided with means for placing it in a vertical
—
position.
Stop-watch or timer of comparable accuracy.
—
1.2.2
Procedure
Work powder sample on a sheet of paper until there is no tendency for the material to pack or
cake. Place the funnel in a vertical position and close the small end with the hand or with a suitable
strip and pour a 100 g sample of powder lightly into the funnel, avoiding any tendency to pack it.
Then quickly open the bottom of the funnel and at the same instant start the stop watch or timer.
Allow the powder to run freely from the funnel, and stop the watch or timer at the instant the last of
it leaves the funnel.
1.2.3
Result
State the time, in seconds, required for the funnel to discharge, to the nearest 0.5 s or, if necessary,
state that the material will not run through the funnel.

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SIST HD 307.2.2 S1:1998
455-2-2 © I E C 1984 — 11 —
1.3 Particle size distribution
The following two methods are applicable:
1.3.1 Dry sieving in accordance with ISO Standard 2591: Test Sieving, with sieve numbers and sizes
specified in Part 3.
1.3.2
Vacuum sieve analysis
Apparatus
— Analytical balance.
— Sieves and transparent sieve cover.
The vacuum sieving device shall be capable of maintaining a vacuum of 125 ± 12.5 mm of water
as measured by a manometer. The slit nozzle which rotates below the sieve shall revolve at a speed
of 25 ± 2 rev/min.
Note. —
Increasingly higher vacuums up to 700 mm of water are maintained for smaller sized sieves.
Procedure
If the coating powders are not to be transferred for weighing, weigh each of the selected sieves and
sample to 0.1 g. If samples are to be transferred from the sieves, weigh sample to 0.0001 g. For sieve
size 32 gm and larger weigh 10.0 g samples. For sieve sizes less than 32 gm, weigh out 1.0 g samples
and transfer to sieve. Put the transparent cover on the sieve and place the sieve in the vacuum
sieving apparatus. Operate the sieving apparatus for 10 min ± 15 s in a vacuum of 150 mm of water
for sieve sizes larger than 74 .trn, a vacuum of 250 mm of water for sieve sizes 74 gm to 20 gm and
700 mm of water for sieve sizes less than 20 gm.
Remove the sieve and cover from the apparatus and weigh to 0.1 g the quantity of material
retained on the sieve or adhering to the cover, then subtract the tare weight from the total. If the
material is transferred to the balance, the sieve shall be carefully brushed on both sides as well as the
cover and weighed to 0.0001 g.
Repeat the procedure for each sieve used. Calculate the percentage of powder retained for each
sieve as follows:
percentage X 100
= S
where :
R = residue mass, in grammes
S = specimen mass, in grammes
1.4
Softening temperature
This is determined in accordance with the requirements Clause 6 of I EC Publication 455-2:
Specification for Solventless Polymerisable Resinous Compounds Used for Electrical Insulation,
Part 2: Methods of Test.
1.5
Gel time
1.5.1 Apparatus
—
Hot plate capable of maintaining the temperature to within ± 1 °C.
If the surface of the hot plate becomes pitted, it should be polished smooth or replaced.

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SIST HD 307.2.2 S1:1998
455-2-2 © I E C 1984 — 13 —
— Stop-watch or timer capable of measuring 0.1 s intervals.
— Wood spatula approximately 2 mm X 10 mm X 150 mm or similar non-heat conducting
stirrer.
Surface pyrometer suitable for use at 150 °C to 250 °C.
—
— 1 ml measuring spoon.
— Mould release agent.
— Metal putty knife.
1.5.2 Procedure
Place the hot plate in a draught-free area or a three-sided 305 mm high draught shield.
Allow at least 30 min for the hot plate to warm up so as to maintain the surface temperature to be
specified in Part 3.
Note. — The hot plate is to be calibrated with the surface pyrometer.
Coat the plate with a thin coat of mould release. Wipe off the excess with a clean towel.
Measure 1 ml of powder and place it on the surface of the hot plate.
Immediately spread the powder with the spatula into a 50 mm diameter circle.
When the powder becomes "wetted", start the stop-watch.
Keep rubbing the molten resin in a circular motion until the resin ceases to flow and forms an
immovable gel, stop the watch and record the time.
After the test is completed, clean the resin from the plate with the metal putty knife.
Repeat the test three times with fresh resin. The results should agree within a 2 s range.
1.6 Non-volatile matter content
The sample size should be 2.0 ± 0.1 g, and the heating times are 1 h at 105 °C and 5 min at
230 °C.
Weigh 2.0 ± 0.1 g of powder into a tared flat-bottomed metal foil dish.
Heat the dish at 105 ± 3 °C for 1 h or at 230 ± 3 °C for 5 min. Cool to room temperature, then
reweigh.
Calculate the non-volatile matter as follows:
(C A)
— Non-volatile matter, percentage = X 100
where:
A = mass of dish, in grammes
B =
mass of sample used, in grammes, and
C = mass of dish and contents after heating, in grammes.
Report the mass of the non-volatile matter as a percentage of the mass of the sample to the
nearest 0.1%.

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SIST HD 307.2.2 S1:1998
OO — 15 —
455-2-2 I E C 1984
SECTION TWO — TESTS FOR MATERIALS IN THE CURED FORM
2.1 Preparation of test specimens
Specimens shall be prepared in accordance with the instructions of the supplier using one of the
two following supports, unless otherwise specified:
— Type A: 150 mm X 200 mm X 1 mm (approximate) clean cold rolled steel plates in accordance
with ISO Standard 683-1: Heat-treated Steels, Alloy Steels and Free-cutting Steels.
— Type B: 10 mm X 10 mm X 150 mm steel bars in accordance with ISO Standard 683-1.
(Ground square to within 0.025 mm with sharp edges).
Prior to coating, the steel should be carefully cleaned with 1,1,1-trichloroethane or any other
suitable grease removing solvent.
Note. — The dimensions given are preferred, others may be used subject to agreement between purchaser and supplier.
Fluidized bed coating is one of the acceptable coating processes for laboratory use.
TABLE I
Number of specimens
Type of support Sub-clause
2.4.2 5
A
B 2.6.2 3
2.7.2 3
A
A 2.8.3 3
2.9 3
A
1
A 2.11
3
B 2.14.3
2.16.3 3
B
Special specimens are required for testing properties described in Sub-clauses 2.5.1, 2.5.4,
Note. —
2.12, 2.17.
To test properties described in Sub-clauses 2.10, 2.13, 2.15, the specimen description is given
in Part 3.
2.2
Visual examination
All specimens shall be examined by normal eyesight for adequate wetting of the substrate, general
rt 3 (e.g. irregularities and inclusions which would affect
appearance and any defect as specified in Pa
the performance of the material).
2.3 Thickness
The thickness of the coating can be measured by means of:
2.3.1 A micrometer as described in Sub-clause 2.1 of I EC Publication 394-2: Vanished Fabrics for
Electrical Purposes, Pa rt 2: Methods of Test.
2.3.2 A suitable microscope.
2.3.3 Magnetic instruments for magnetic base materials.

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SIST HD 307.2.2 S1:1998
— 17 —
455-2-2 © I E C 1984
2.4 (test for uniformity)
Porosity of coating
2.4.1 Apparatus
2.4.1.1 High-voltage generator
The high-voltage generator shall generate a d.c. test voltage which is adjustable between + 5% and
— 10%.
The internal resistance shall be chosen so that the steady state short-circuit current has an average
value of 3 ± 0.3 mA.
During a high voltage flashover the maximum value of the current shall be between 10 mA and
mC.
50 mA. The charge of the pulse shall not exceed 25 X 10- 3
One pole of the high-voltage generator shall be connected to the protective conductor or to the
body of the high-voltage generator. The other pole of the high-voltage generator shall lead to the
high-voltage testing head through a screened high-voltage cable. The high-voltage generator shall be
provided with a device which optically and/or acoustically clearly indicates each spark discharge at
the test electrode.
2.4.1.2 High-voltage testing head
The testing head shall be provided with an electrically conductive sheath which is connected to
the protective conductor of the apparatus.
A protective resistor shall be mounted in the testing head for limiting the current (from 10 mA up
to a maximum of 50 mA) during the high-voltage flashover.
2.4.1.3 Electrodes
The electrodes shall consist of either flexible metal brushes whose bristles closely fit the surface of
the specimen without leaving any free space during brushing of the surface or conductive
rubber.
2.4.2 Test specimens
s (see Sub-clause 2.1); five specimens shall be prepared.
Use Type A support
2.4.3 Procedure
The test voltage of 15 kV/mm is adjusted and the test electrode having a large contact area is
moved with a maximum speed of 4 cm/s across the surface of the specimen. During this time, the
test voltage is to be observed. The test voltage may drop by no more than 10%. Pores and flaws are
indicated by visible sparks on the test electrode and simultaneously by an optical and/or acoustic
signal.
2.4.4 Results
The number of pores or flaws occurring on each specimen shall be reported.
2.5 Scratch hardness
This is determined in accordance with either Method 1 of ISO Standard 1518: Paints and
Varnishes — Scratch Test, or in accordance with Method 2.

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SIST HD 307.2.2 S1:1998
455-2-2 © I E C 1984 — 19 —
Method 1
2.5.1 ISO Standard 1518 specifies a test procedure for determining under standard conditions the
resistance to penetration by scratching with a needle of a single coating or a multicoat system of
paint, varnish or related product. Either a single specified load is applied to the needle (go/no-go
test) or increasing loads are applied to the needle to determine the minimum load at which the
coating is fully penetrated to the substrate.
Method 2
2.5.2 Purpose
This test determines the mechanical resistance of the surface of a specimen coated with a pow-
dered resinous compound against the penetration of a sharp object under the effect of a load.
2.5.3 Testing apparatus
2.5.3.1 A scratch hardness testing apparatus permitting the determination of the force, in newtons, at
which a scratch diamond of defined dimensions causes a scratch — recognizable by means of a
magnifying glass — on the steel substrate surface. The scratch diamond has the following dimen-
sions:
acute angle: 50°
radius: 17 ± 2 gm
The apparatus consists essentially of a rotating turntable (1 rev/min) and a scale arm which rests
on the specimen. A scratch diamond is horizontally positioned on the arm which may be loaded by
detachable weights.
2.5.3.2 Magnifying glass with magnification 10 X.
2.5.4
Specimens
Three steel plates (2 mm X 100 mm X 100 mm) of the type of steel as described for Type A
support, with 7 mm diameter holes in the centre, are prepared.
2.5.5 Procedure
The specimen is placed on the turntable and is lightly pressed to it by means of a knurled nut. The
scale arm is carefully place
...