IEC 61189-3:1997/AMD1:1999

INTERNATIONAL IEC
STANDARD
61189-3
AMENDMENT 1
1999-07
Amendment 1
Test methods for electrical materials,
interconnection structures and assemblies –
Part 3:
Test methods for interconnection structures
(printed boards)
Amendement 1
Méthodes d'essai pour les matériaux électriques,
les structures d'interconnexion et les ensembles –
Partie 3:
Méthodes d'essai des structures d'interconnexion
(cartes imprimées)
 IEC 1999  Copyright - all rights reserved
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
Commission Electrotechnique Internationale
PRICE CODE
V
International Electrotechnical Commission
For price, see current catalogue

– 2 – 61189-3 Amend. 1  IEC:1999(E)

FOREWORD
This amendment has been prepared by IEC technical committee 52: Printed circuits.

The text of this amendment is based on the following documents:

FDIS Report on voting
52/805/FDIS 52/825/RVD
Full information on the voting for the approval of this amendment can be found in the report on
voting indicated in the above table.
A bilingual version of this amendment may be issued at a later date.
___________
Page 3
CONTENTS
Add the following figures to the list of figures:
Figure 10 – Needle burner test
Figure 11 – Pencil holder
Figure 12 – Composite test pattern
Figure 13 – Test specimen
Page 9
2 Normative references
Insert, in the existing list, the titles of the following standards:

IEC 60454-1:1992, Specifications for pressure-sensitive adhesive tapes for electrical purposes –
Part 1: General requirements
IEC 60695-2-2:1991, Fire hazard testing – Part 2: Test methods – Section 2: Needle-flame test
IEC 62326-4:1996, Printed boards – Part 4: Rigid multilayer printed boards with interlayer
connections – Sectional specification
IEC 62326-4-1:1996, Printed boards – Part 4: Rigid multilayer printed boards with interlayer
connections – Sectional specification – Section 1: Capability Detail Specification –
Performance levels A, B and C
ISO 4046:1978, Paper, board, pulp and related terms – Vocabulary

61189-3 Amend. 1  IEC:1999(E) – 3 –

Page 17
7.2 Test 3D02: Conductor width and spacing (under consideration)

Replace this subclause by the following subclause:

7.2 Test 3D02: Conductor width and spacing

7.2.1 Object
The purpose of this test method is to provide a procedure for determining the conductor width

and spacing of a printed board.
7.2.2 Test specimens
The specimen shall be a suitable printed board having conductor patterns for test.
Where the use of test coupons, as specified in IEC 62326-4-1, is agreed between the user and
the supplier, the measurement shall be carried out on specimen F.
7.2.3 Test apparatus and materials
An iIlluminated eyepiece or microscope or projector having an ocular micrometer with a res-
olution of 0,01 mm or better shall be used.
7.2.4 Procedure
The conductor width and spacing between conductors shall be measured at random points,
including central and corner areas, according to the relevant specification, and viewed
vertically from above. The measured value shall be recorded to the nearest 0,01 mm. Edge
defects such as indentations, projections, and slivers shall be excluded from measurement.
7.2.5 Report
The report shall include
a) the test method number and revision;
b) the date of the test;
c) the identification and description of the specimen;
d) the conductor width and spacing measured;
e) the layer number;
f) the number of measurements;
g) the maximum and minimum observed conductor widths and spaces;
h) the average conductor width and spaces;
i) any deviation from this test method;
j) the name of the person conducting the test.
7.2.6 Additional information
None.
– 4 – 61189-3 Amend. 1  IEC:1999(E)

Page 19
8.3 Test 3C03: Flammability; rigid printed board needle plane test (under consideration)

Replace this subclause by the following subclause:

8.3 Test 3C03: Flammability; needle flame test, rigid printed boards

8.3.1 Object
The object of the test is to determine the effect upon a printed board of exposure to a glowing

wire under specific conditions.
The intensity of the ignition source is similar to that of an accidentally overheating or glowing of
a single electronic component.
Reference should be made to 8.3 of IEC 60326-3, with regard to the fire integrity of printed
boards and the suitability of test methods.
Timings measured by this test are an indication of the ability of the printed board to self-
extinguish. There is no correlation with other properties of the material(s), such as the oxygen
index.
8.3.2 Test specimen
The test specimen shall be a production board or a test board that is representative of the
production board in terms of:
– base material(s);
– surface coating(s);
– type (for example multilayer, single-sided, etc.);
–size;
– design;
– surface area;
– thickness;
– metal distribution.
Test boards of 150 mm × 150 mm may be considered large enough to represent larger
production boards. Smaller production boards should be tested in their actual size.

A minimum of five specimens shall be tested.
8.3.3 Test apparatus and materials
The following test apparatus and materials shall be used:
a) A room or compartment, in which the test is conducted, having dimensions adequate to
ensure that the test is carried out in a substantially draught-free atmosphere, but which
allows a sufficient supply of air for normal combustion. Subdued light is advantageous.
b) A burner to produce the test flame, which is a tube with a length of at least 35 mm with an
internal diameter of (0,5 ± 0,1) mm and an external diameter not exceeding 0,9 mm. The
burner shall be held in a movable fixture.

61189-3 Amend. 1  IEC:1999(E) – 5 –

c) A burner shall be supplied with butane gas having a minimum purity of 95 %. No air may be

admitted to the burner tube. Propane gas may be used, but butane gas shall be the

reference.
The burner shall be adjusted whilst in a vertical axis, in order to produce a flame having a

height of (12 ± 1) mm. See figure 10a.

d) A wooden board to be placed underneath the specimen. The board shall be covered with

tissue paper which complies with 6.86 of ISO 4046. The distance between the lower edge

of the specimen and the tissue paper shall be (200 ± 5) mm.

e) A hand-operated timing device with a resolution of ±0,5 s or better.

f) An air circulating oven capable of maintaining (125 ± 5) °C.

g) A desiccator capable of maintaining 20 % R.H. or less.
8.3.4 Test procedure
The test specimens shall be pre-conditioned for 24 h at (125 ± 5) °C in an air-circulating oven.
The test specimens shall then be allowed to stabilize for 4 h at room temperature in a
desiccator over anhydrous calcium chloride.
The relevant specification shall detail the position of the test specimen and the point of
application of the flame (for example surface, edge). The attitude of the specimen (for example
horizontal or vertical) should mimic the intended mode of operation in the assembled
equipment.
Where surface application is used, the point of application of the flame shall, specimen size
permitting, not be less than 10 mm from the nearest edge, in order to minimize edge effects.
Where edge application is used, the flame shall not, specimen size permitting, be less than
10 mm from the nearest corner.
The burner shall be mounted at an angle of about 45°, so that any drops from the test
specimen can fall freely onto the underlying tissue paper.
If the intended operational attitude of the printed board is not known or is variable, the test
specimens shall be positioned as follows.
Edge application: The lower edge shall be horizontal and the specimen shall be inclined at
approximately 80°. The flame shall be applied to the lower side of the test specimen.
The burner shall be ignited away from the test specimen, and the height of the flame shall be

adjusted to (12 ± 2) mm. The burner shall then be positioned as described, so that the test
specimen penetrates the flame by approximately 2 mm. A vertical distance of between 8 mm
and 10 mm from the tip of the burner and the surface or edge to be tested is adequate for this
purpose. In the case of application to a vertical surface, a horizontal distance of approximately
5 mm is necessary.
The detail specification shall state the severity to be used.
Test flame application times as detailed in clause 5 of IEC 60695-2-2 are preferred. These
severities are: 5 s - 10 s - 20 s - 30 s - 60 s - 120 s.

– 6 – 61189-3 Amend. 1  IEC:1999(E)

8.3.5 Report
The report shall include
a) the test number and revision;

b) the date of the test;
c) the identification and description of the specimen;

d) the number of specimens, if other than five;

e) the position of the test specimens;

f) the point of application of the test flame;

g) the duration of application of the test flame;
h) for each specimen whether flames and/or burning or glowing particles fall from the test
specimen spreading fire to surrounding parts of the test specimen or to the tissue paper
beneath the test specimen;
i) for each specimen whether there is flame or glowing at the end of the application of the test
flame;
j) for each specimen whether the duration of burning is less than 30 s;
k) any deviation from this test method;
l) the name of the person conducting the test.
8.3.6 Additional information
There are obvious hazards associated with flammability testing. Training of test operators and
familiarity with laboratory safety procedures is of paramount importance.
The smoothness of the specimen edges can be critical to the performance of the sample. A
polished finish is recommended. A rough finish (for example blanked) will significantly degrade
performance due to the increase in surface area available to the flame.
Small-scale flammability tests, such as the one described herein, are an indicator of the
behaviour of the material(s) tested. Fire integrity of equipment in which printed boards are used
can only be assessed by equipment level testing.

61189-3 Amend. 1  IEC:1999(E) – 7 –

Detail requirements to be stated in specifications which reference this test method should be
based on clause 11 of IEC 60695-2-2.

10 mm
Specimen
Penetration of flame: approximately 2 mm

Burner
45°
IEC  857/99
Figure 10a – Horizontal specimen – Flame applied to surface
Specimen
Penetration of flame: approximately 2 mm
Burner
45°
IEC  858/99
Figure 10b – Horizontal specimen – Flame applied to edge

– 8 – 61189-3 Amend. 1  IEC:1999(E)

Specimen
Penetration of flame: approximately 2 mm

8 mm
to
10 mm
Burner
45°
IEC  859/99
Figure 10c – Vertical specimen – Lower edge horizontal – Flame applied to edge
Penetration of flame: approximately 2 mm
Specimen
Burner
Approximately
5 mm
45°
IEC  860/99
Figure 10d – Vertical specimen – Lower edge horizontal – Flame applied to surface

61189-3 Amend. 1  IEC:1999(E) – 9 –

Penetration of flame: approximately 2 mm

Specimen
Burner
80°
45°
IEC  861/99
Figure 10e – Needle burner test – Side views of test board and burner
Figure 10 – Needle burner test
Page 27
9.8 Test 3M08: Resistance of abrasion of printed board organic surface coatings
(under consideration)
Replace this subclause by the following subclause:
9.8 Test 3M08: Hardness (resistance to abrasion) of organic surface coatings
of printed circuit boards
9.8.1 Object
This test method details the procedure for the determination of the hardness of permanent
organic surface coatings used on printed boards.

– 10 – 61189-3 Amend. 1  IEC:1999(E)

Organic materials suitable for testing in accordance with this procedure include:

– permanent polymeric coatings;

– conductive inks;
– marking legend inks.
Hardness is determined by comparison with a standard set of pencils with increasing hardness.

9.8.2 Test specimens
The test specimen shall consist of a piece of metal-clad base material

(100 ± 10) mm × (100 ± 10) mm, with the organic surface coating applied and cured as
recommended by the supplier.
Alternatively, a coated portion of a production board may be used as agreed between the
customer and the supplier.
A minimum of three specimens (separate boards) shall be tested.
9.8.3 Test apparatus and materials
The following test apparatus and materials shall be used.
a) Test device (pencil holder, see figure 11).
b) Standard set of pencils of hardness from 4B to 8H.
4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H
Soft –––––––––––––––––––––––––––––––––––––––––––––––––– Hard
9.8.4 Procedure
Place the specimen on a firm horizontal surface.
The tips of all pencils shall be sharpened as shown in figure 11.
Starting with the hardest pencil in the carriage, push the carriage in the direction as illustrated
in figure 11 with a uniform forward force in a 20 mm to 30 mm stroke, whereby, because of the
weight of the specimen holder of (750 ± 25) g, a downard directed force of (7,65 ± 0,25) N will
result at the pencil tip. Proceed with the next softest pencil in succession until a pencil is used
which will not cut into or gouge the coating material. Used pencils shall be resharpened after

every test.
The hardness is an attribute, rather than a variable. No statement of uncertainty is required.
9.8.5 Report
The report shall include
a) the test method and revision;
b) the date of the test;
c) the identification and description of the specimen(s);

61189-3 Amend. 1  IEC:1999(E) – 11 –

d) the achieved hardness; i.e. the hardness of the pencil which failed to cut into or gouge the

organic surface coating;
e) the supplier and description of the pencil set;

f) any deviation from this test method;

g) the name of the person conducting the test.

9.8.6 Additional information
It is accepted that the results achieved using this test method are subjective in nature. To limit

this subjectivity, it is recommended that only professional grade draftsman’s pencils are used.

Where disputes between testing agencies result, an agreed single source of pencil should be
used for the test.
...