IEC 63294:2021
(Main)Test methods for electric cables with rated voltages up to and including 450/750 V
Test methods for electric cables with rated voltages up to and including 450/750 V
IEC 63294:2021 specifies the test methods for electric cables with rated voltages up to and including 450/750 V not included in the IEC 60811 series.
Méthodes d'essais pour les câbles électriques de tension assignée au plus égale à 450/750 V
L'IEC 63294:2021 spécifie les méthodes d'essais pour les câbles électriques de tension assignée au plus égale à 450/750 V, qui ne sont pas fournies dans la série IEC 60811.
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IEC 63294 ®
Edition 1.0 2021-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Test methods for electric cables with rated voltages up to and including
450/750 V
Méthodes d'essais pour les câbles électriques de tension assignée au plus
égale à 450/750 V
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IEC 63294 ®
Edition 1.0 2021-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Test methods for electric cables with rated voltages up to and including
450/750 V
Méthodes d'essais pour les câbles électriques de tension assignée au plus
égale à 450/750 V
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.20 ISBN 978-2-8322-1041-2
– 2 – IEC 63294:2021 © IEC 2021
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 General requirements . 8
4.1 Sampling. 8
4.2 Pre-conditioning . 8
4.3 Test temperature . 8
4.4 Test voltage . 8
4.5 Test values . 8
5 Electrical test methods . 8
5.1 Electrical resistance of conductors . 8
5.2 Voltage test carried out on completed cables . 9
5.3 Voltage test on cores in water . 9
5.3.1 General . 9
5.3.2 Test sample . 9
5.3.3 Procedure . 9
5.3.4 Requirements . 9
5.4 Insulation resistance . 9
5.5 Insulation resistance at temperatures above 90 °C . 10
5.6 Long-term resistance of insulation to direct current . 11
5.6.1 Test sample . 11
5.6.2 Procedure . 11
5.6.3 Requirements . 11
5.7 Absence of faults in insulation. 11
5.7.1 General . 11
5.7.2 Spark test . 12
5.7.3 Voltage test . 12
5.8 Surface resistance of sheath . 12
5.8.1 Test samples . 12
5.8.2 Procedure . 12
5.8.3 Requirements . 13
6 Non-electrical test methods . 13
6.1 Checking of the durability of colours and markings . 13
6.2 Measurement of thickness of insulation . 13
6.2.1 Procedure . 13
6.2.2 Evaluation of results . 13
6.3 Measurement of thickness of sheath . 13
6.3.1 Procedure . 13
6.3.2 Evaluation of results . 13
6.4 Measurement of overall dimensions and ovality . 13
6.5 Solderability test for non-tinned conductors . 14
6.5.1 General . 14
6.5.2 Selection of samples and preparation of test pieces . 14
6.5.3 Description of the solder bath . 14
6.5.4 Test procedure . 15
6.5.5 Requirements . 15
6.6 Flexing test . 15
6.6.1 General . 15
6.6.2 Apparatus . 15
6.6.3 Sample preparation . 16
6.6.4 Current applied on cores . 16
6.6.5 Voltage between cores . 16
6.6.6 Fault detection (construction of the flexing apparatus) . 17
6.7 Static flexibility test . 17
6.8 Bending test . 18
6.9 Wear resistance test . 19
6.10 Drop test . 20
6.11 Void . 20
6.12 Three-pulley flexing test . 20
6.12.1 Test method . 20
6.12.2 Requirements . 22
6.13 Kink test . 22
6.13.1 Applicability . 22
6.13.2 Apparatus . 22
6.13.3 Sample . 22
6.13.4 Test procedure . 22
6.13.5 Requirements . 22
6.14 Tests for mechanical properties after air oven ageing of insulation consisting
of rubber compound . 23
6.14.1 General . 23
6.14.2 Sampling and preparation . 24
6.14.3 Ageing procedure . 24
6.14.4 Preparation of test pieces and tensile test . 24
6.15 Test for resistance to heat of textile braids . 24
6.15.1 General . 24
6.15.2 Apparatus . 24
6.15.3 Test sample . 24
6.15.4 Preparation . 24
6.15.5 Test procedure . 25
6.15.6 Requirements . 25
6.16 Tesf for resistance of sheath to water . 25
6.16.1 General . 25
6.16.2 Sampling and preparation of test pieces . 25
6.16.3 Procedure . 26
6.16.4 Evaluation of results . 26
6.17 Chemical test: Determination of halogens – Elemental test . 26
6.17.1 Equipment . 26
6.17.2 Materials . 26
6.17.3 Procedure . 26
Annex A (informative) Cross-references table . 28
Bibliography . 29
– 4 – IEC 63294:2021 © IEC 2021
Figure 1 – Positioning of electrodes . 11
Figure 2 – Flexing apparatus . 16
Figure 3 – Static flexibility test . 18
Figure 4 – Bending test apparatus . 19
Figure 5 – Arrangement for wear-resistance test . 20
Figure 6 – Modified carrier C . 21
Figure 7 – Kink test apparatus . 23
Figure 8 – Assembled test apparatus . 25
Table A.1 – Cross-references for tests . 28
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TEST METHODS FOR ELECTRIC CABLES WITH
RATED VOLTAGES UP TO AND INCLUDING 450/750 V
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 international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
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Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
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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.
IEC 63294 has been prepared by IEC technical committee 20: Electric cables. It is an
International Standard.
This first edition cancels and replaces IEC 60227-2:1997, IEC 60227-2:1997/AMD1:2003,
IEC 60245-2:1994, IEC 60245-2:1994/AMD1:1997, IEC 60245-2:1994/AMD2:1997, IEC 62821-
2:2015 and IEC 63010-2:2017. A table of cross-references for tests is given in Annex A.
The text of this International Standard is based on the following documents:
Draft Report on voting
20/1970/FDIS 20/1990/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
– 6 – IEC 63294:2021 © IEC 2021
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under 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.
TEST METHODS FOR ELECTRIC CABLES WITH
RATED VOLTAGES UP TO AND INCLUDING 450/750 V
1 Scope
This document specifies the test methods for electric cables with rated voltages up to and
including 450/750 V not included in the IEC 60811 series.
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 60811-201, Electric and optical fibre cables – Test methods for non‑metallic materials –
Part 201: General tests – Measurement of insulation thickness
IEC 60811-202, Electric and optical fibre cables – Test methods for non‑metallic materials –
Part 202: General tests – Measurement of thickness of non-metallic sheath
IEC 60811-203, Electric and optical fibre cables – Test methods for non‑metallic materials –
Part 203: General tests – Measurement of overall dimensions
IEC 60811-401:2012, Electric and optical fibre cables – Test methods for non‑metallic materials
– Part 401: Miscellaneous tests – Thermal ageing methods – Ageing in an air oven
IEC 60811-501, Electric and optical fibre cables – Test methods for non‑metallic materials –
Part 501: Mechanical tests – Tests for determining the mechanical properties of insulating and
sheathing compounds
IEC 62230, Electric cables – Spark-test method
IEC 60502-1, Power cables with extruded insulation and their accessories for rated voltages
from 1 kV (U = 1,2 kV) up to 30 kV (U = 36 kV) – Part 1: Cables for rated voltages of 1 kV
m m
(U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
ISO 1302, Geometrical Product Specifications (GPS) – Indication of surface texture in technical
product documentation
3 Terms and definitions
No terms and definitions are listed in this document.
IEC and ISO 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
– 8 – IEC 63294:2021 © IEC 2021
4 General requirements
4.1 Sampling
If a marking is in relief in insulation or sheath, the samples used for the tests shall be taken so
as to include such marking.
For multicore cables, except for the test specified in 5.6 and in 6.2, not more than three cores
(of different colours, if applicable) shall be tested unless otherwise specified.
4.2 Pre-conditioning
All the tests shall be carried out not less than 16 h after the extrusion or vulcanization of the
insulating or sheathing compounds.
4.3 Test temperature
Unless otherwise specified in the relevant cable standard, tests shall be made at an ambient
temperature of (20 ± 15) °C.
4.4 Test voltage
Unless otherwise specified in the relevant cable standard, the test voltages shall be alternating
current of approximately sinewave form and of frequency between 49 Hz and 61 Hz. The ratio
with a tolerance of ±7 %.
of peak value to RMS value shall be equal to 2
The values quoted are RMS values.
4.5 Test values
Full test conditions (such as temperatures, durations) and full test requirements are not
specified in this document. It is intended that they should be specified by the relevant cable
standard.
Any test requirements which are given in this document may be modified by the relevant cable
standard to suit the needs of a particular type of cable.
5 Electrical test methods
5.1 Electrical resistance of conductors
In order to check the electrical resistance of conductors, the resistance of each conductor shall
be measured on a sample of cable of at least 1 m in length. The length of each sample shall be
measured.
If necessary, a correction to 20 °C and to a length of 1 km shall be obtained by the formula:
254,5 1 000
RR= ××
20 t
234,5 + t L
where
R is the resistance at 20 °C, in ohms/kilometre;
R is the resistance of L metres of cable at t °C, in ohms;
t
t is the temperature of the sample at the moment of measurement, in degrees Celsius;
L is the length of the sample of cable, in metres (length of the complete sample and not of
the individual cores or wires).
5.2 Voltage test carried out on completed cables
A sample of cable as delivered shall be immersed in water. The length of the sample, the
temperature of the water and the duration of immersion and the test voltage shall be given in
the relevant cable standard.
A voltage shall be applied in turn between each conductor and all the others together, connected
to the metallic layer or metallic component, if any, or to the water; and then between all
conductors together and the metallic layer or metallic component, if any, or to the water.
No breakdown of the insulation shall occur during the test.
5.3 Voltage test on cores in water
5.3.1 General
The test applies to sheathed cables, braided cables and flat non-sheathed cables.
5.3.2 Test sample
Prepare a sample of cable 5 m long, by carefully removing, without damaging the cores, the
sheath or the overall braid and any other covering or fillers from a length of completed cable.
In the case of a flat non-sheathed cable, take a 5 m sample and make a cut in the insulation
between the cores and separate the cores by hand over a length of 2 m, without damaging the
cores.
5.3.3 Procedure
Immerse the sample in water at the temperature, and for the period specified in the relevant
cable standard. Ensure that the ends of the cores protrude above the water by a distance
sufficient to prevent excessive surface leakage when the test voltage is applied. Apply a voltage
between the conductors and the water, of the magnitude and for the time specified in the
relevant cable standard.
5.3.4 Requirements
No breakdown of the insulation shall occur during the test.
5.4 Insulation resistance
This test shall be made on the core samples, 5 m in length, previously submitted to the test
described in 5.3 or, if this is not applicable, to the test described in 5.2.
The sample shall be immersed in water previously heated to the temperature indicated in the
relevant cable standard. A length of about 0,25 m at each end of the sample shall be kept above
the water.
The length of the samples, the temperature of the water and the duration of immersion shall be
given by the relevant cable standard.
A DC voltage of between 80 V and 500 V shall then be applied between the conductor and the
water.
The insulation resistance shall be measured 1 min after application of the voltage. The
measured value shall be expressed in MΩ · km.
– 10 – IEC 63294:2021 © IEC 2021
None of the resulting values shall be below the minimum insulation resistance value specified
in the relevant cable standard.
NOTE The minimum values of the insulation resistance can be calculated (based on a volume resistivity of
1 × 10 Ω · m) from the formula:
D
R,= 0 0367 log
d
where:
R is the insulation resistance, in MΩ · km;
D is the nominal outer diameter of the insulation, in mm;
d is the diameter of the circumscribed circle of the conductor or, for tinsel cables, the nominal inner diameter of
the insulation, in mm.
5.5 Insulation resistance at temperatures above 90 °C
This test method applies to cables or cores with maximum rated conductor temperatures above
90 °C.
This test shall be made on the core samples previously submitted to the test described in 5.3
or, if this is not applicable, to the test described in 5.2.
A sample of 1,40 m in length shall be cut from the cable or core to be tested. Cover the central
part of this test piece with a semi-conducting layer, and over this layer apply a metal braid or a
metal tape in such a way as to obtain an active measuring length of 1,0 m.
At both ends of the active measuring length, leaving a gap 1 mm wide, a protective wire binding
of approximately 5 mm wide shall be applied; any semi-conducting material covering the gap
shall be removed (see Figure 1).
The sample shall then be wound to a ring with a diameter of approximately 15 D but at least
0,20 m (D is the nominal outer diameter of insulation).
The samples shall be maintained in an air oven for at least 2 h at the test temperature specified
in the relevant cable standard. The clearance between the sample and the walls of the air oven
shall be at least 50 mm.
After the conditioning period a DC voltage between 80 V and 500 V shall be applied between
the conductor and the screen (semi-conducting layer and metal braid or metal tape including
the protective wire binding being earthed), the sample still being kept in the air oven.
The insulation resistance shall be measured 1 min after application of the voltage and this value
shall be used to calculate the insulation resistance of a 1 km length of cable. The measured
value shall be expressed in MΩ · km. See note under 5.4.
None of the resulting values shall be below the minimum insulation resistance value specified
in the relevant cable standard.
Key
1 guard electrode (protective wire binding)
2 screen electrode
Figure 1 – Positioning of electrodes
5.6 Long-term resistance of insulation to direct current
5.6.1 Test sample
Carry out the test on a sample of cable of 5 m in length from which all coverings have been
removed. The cores of flat non-sheathed cables shall not be separated. Ensure any damage to
the core(s) is avoided during removal of the coverings.
For cables having up to five cores, each core shall be tested. For multicore cables having more
than five cores, one core of each colour in the cable shall be tested, and where the number of
colours is less than five, duplicated coloured cores shall be tested as necessary to bring the
number of cores tested up to a minimum of five.
5.6.2 Procedure
Immerse the sample, for the period and at the temperature given in the relevant cable standard,
in an aqueous solution of sodium chloride having a concentration of 10 g/l, with a length of
about 250 mm at each end of the sample projecting above the solution. Connect the negative
pole of a 220 V DC supply to the conductor(s) of the sample and the positive pole to a copper
electrode immersed in the solution for the time given in the relevant cable standard.
5.6.3 Requirements
No breakdown of the insulation shall occur during the test and, after the test, the exterior of the
insulation shall show no sign of damage.
Discoloration of the insulation should be ignored.
5.7 Absence of faults in insulation
5.7.1 General
Test all the cable that is in the final stage of manufacture, whether it is in delivery lengths or in
manufacturing lengths prior to being cut into delivery lengths.
– 12 – IEC 63294:2021 © IEC 2021
Test single core cables, whether sheathed or non-sheathed, by the spark test in accordance
with 5.7.2. Test all other cables, including sheathed flat cables, with the voltage test in
accordance with 5.7.3.
The requirements of 4.2 do not apply when the check for absence of faults is carried out as a
routine (R) test.
5.7.2 Spark test
5.7.2.1 Procedure
Carry out the test in accordance with IEC 62230, except that the option to use a pulsed
waveform high-voltage source is not permitted.
5.7.2.2 Requirements
No faults shall be detected during the test.
5.7.3 Voltage test
5.7.3.1 Procedure
With the cable in the dry state and at ambient temperature, apply a voltage of the magnitude
given in the relevant cable standard, supplied either from an AC source or from a DC source,
between each conductor and all the other conductors and the metallic layer if any, connected
to earth.
Increase the voltage gradually and maintain it at the full value for the duration given in the
relevant cable standard.
5.7.3.2 Requirements
No breakdown of the insulation shall occur during the test.
5.8 Surface resistance of sheath
5.8.1 Test samples
Carry out the test on three samples of completed cable, each about 250 mm in length.
5.8.2 Procedure
Clean the sheath of each of the samples with industrial methylated spirit, and apply two
electrodes consisting of wire helices of copper wire of between 0,2 mm and 0,6 mm diameter,
at a distance of (100 ± 2) mm from each other to each sample. After the wire has been applied,
clean the surface of the sheath again thoroughly between the electrodes.
Condition the samples with electrodes attached in a conditioning chamber at a temperature of
(20 ± 2) °C and a relative humidity of (65 ± 5) % for 24 h.
Immediately after removal from the conditioning chamber, apply a DC voltage of between 100 V
and 500 V between the electrodes, and measure the resistance after 1 min.
Multiply the measured resistance of each sample, in ohms, by a/100, where a is the
circumference of the sheath of the sample, in millimetres. Record the median of the three values
so obtained as the surface resistance of the sheath.
5.8.3 Requirements
The median of the three values so obtained shall be not lower than the value in the cable
standard.
6 Non-electrical test methods
6.1 Checking of the durability of colours and markings
Compliance with this requirement shall be checked by trying to remove the marking of the
manufacturer's name or trade mark and the colours of cores or numerals by rubbing lightly ten
times with a piece of cotton wool or cotton cloth soaked in water.
6.2 Measurement of thickness of insulation
6.2.1 Procedure
The thickness of insulation shall be measured in accordance with IEC 60811-201.
One sample of cable shall be taken from each of three places, separated by at least 1 m.
The preparation of the test pieces shall be done in accordance with IEC 60811-501.
Compliance shall be checked on each core of cables having up to five cores, and on any five
cores of cables with more than five cores.
6.2.2 Evaluation of results
The mean of the 18 values (expressed in millimetres) obtained from the three pieces of
insulation from each core shall be calculated to two decimal places and rounded as specified
in IEC 60502-1, and this shall be taken as the mean value of the thickness of insulation.
The lowest of all values obtained shall be taken as the minimum thickness of insulation at any
point.
6.3 Measurement of thickness of sheath
6.3.1 Procedure
The thickness of sheath shall be measured in accordance with IEC 60811-202.
One sample of cable shall be taken from each of three places, separated by at least 1 m.
6.3.2 Evaluation of results
The mean of all the values (expressed in millimetres) obtained from the three pieces of sheath
shall be calculated to two decimal places and rounded as specified in IEC 60502-1, and this
shall be taken as the mean value of the thickness of sheath.
The lowest of all values obtained shall be taken as the minimum thickness of sheath at any
place.
6.4 Measurement of overall dimensions and ovality
The three samples taken in accordance with 6.2 or 6.3 shall be used.
– 14 – IEC 63294:2021 © IEC 2021
The measurement of the overall diameter of any circular cable and of the overall dimensions of
flat cables with a major dimension not exceeding 15 mm shall be carried out in accordance with
IEC 60811-203.
For the measurement of flat cables with a major dimension exceeding 15 mm, a micrometer, a
profile projector or similar device shall be used.
The mean of the values obtained shall be taken as the mean overall dimension.
For checking the cable ovality of circular sheathed cables, the difference between any two
values of the overall diameter of sheathed circular cables of the same cross-section (ovality)
shall not exceed 15 % of the mean overall diameter.
6.5 Solderability test for non-tinned conductors
6.5.1 General
The test is intended to verify the effectiveness of the separator between the non-tinned
conductor and the insulation.
6.5.2 Selection of samples and preparation of test pieces
One sample having a length suitable for the bending test defined in 6.8 is taken at three points
in the cable, and the cores in each sample are carefully separated from all other components.
Each sample of core thus obtained is wound for three turns on a mandrel, the diameter of which
is a maximum of three times that of the core.
The sample is then unwound and straightened out, whereupon it is wound again in such a way
that the side which was compressed in the first case becomes the stretched fibre in the second.
This cycle of operations is repeated two more times, which represents three bending operations
in one direction and three in the other.
From each sample of core which has been straightened out after the third cycle of bending
operations, a test piece having a length of about 15 cm is taken from that part of the core which
has actually been wound.
Each test piece is then subjected to accelerated ageing in an air oven for 240 h at a temperature
of 70 °C ± 1 °C.
After this accelerated ageing, the test pieces are left at ambient temperature for at least 16 h.
Then each test piece is stripped at one end over a length of 60 mm and is subjected to the
solderability test by the solder-bath method described in 6.5.4.
6.5.3 Description of the solder bath
The solder bath shall have a volume sufficient to ensure that the temperature of the solder
remains uniform when the conductor is introduced. It shall be provided with a device which
maintains the temperature of the solder at 270 °C ± 10 °C.
The depth of the solder bath shall be at least 75 mm.
The visible surface area of the bath shall be reduced as far as possible, by using a perforated
plate of heat resistant material in order to protect the core against direct radiation from the bath.
The composition of the solder shall be tin (between 59,5 % and 61,5 %) and lead.
Impurities (as a percentage of the total mass) shall not exceed:
Antimony 0,50 % Zinc 0,005 %
Bismuth 0,25 % Aluminium 0,005 %
Copper 0,08 % Others 0,080 %
Iron 0,02 %
6.5.4 Test procedure
The surface of the solder bath shall be kept clean and shiny.
After immersion for 10 s at ambient temperature in a pickling bath consisting of a solution of
zinc chloride in water (ZnCl being 10 % of the total mass), the bare end of each test piece
shall be immersed in the solder bath over a length of 50 mm in the direction of its longitudinal
axis.
The speed of immersion is 25 mm/s ± 5 mm/s.
The duration of immersion, after 50 mm of the sample is fully immersed, is 5 s ± 0,5 s.
The speed of emergence is 25 mm/s ± 5 mm/s.
Each test piece shall be subjected to three immersion cycles with a period of 10 s between each
cycle.
6.5.5 Requirements
The part of the conductor that has been immersed shall be adequately tinned. The result is that
the tinning should completely cover that treated area and not reveal any part of the conductor
beneath.
6.6 Flexing test
6.6.1 General
This test is applicable to flexible cables with cores of nominal cross-sectional area up to and
including 4 mm .
This test is not applicable to cables having more than 18 cores laid up in more than two
concentric layers.
Test requirements are shown in the relevant cable standard.
6.6.2 Apparatus
This test shall be carried out by means of the apparatus shown in Figure 2. This apparatus
consists of a carrier C, a driving system for the carrier and four pulleys for each sample of cable
to be tested. The carrier C supports two pulleys A and B, which are of the same diameter. The
two fixed pulleys, at either end of the apparatus, may be of a different diameter from pulleys A
and B, but all four pulleys shall be so arranged that the sample is horizontal between them. The
carrier makes cycles (forward and backward movements) over a distance of 1 m at an
approximately constant speed of 0,33 m/s between each reversal of the direction of movement.
– 16 – IEC 63294:2021 © IEC 2021
The pulleys shall be made of metal and have a semi-circular shaped groove for circular cables
and a flat groove for flat cables. The restraining clamps D shall be fixed so that the pull is
always applied by the weight from which the carrier is moving away. The distance from one
restraining clamp to its support, while the other clamp is resting on its support, shall be of 5 cm
maximum.
The driving system shall be such that the carrier turns smoothly and without jerks when it
reverses from one direction to another.
Key
A pulley
B pulley
C carrier
D restraining clamps
Figure 2 – Flexing apparatus
6.6.3 Sample preparation
A sample of flexible cable about 5 m long shall be routed through the pulleys, as shown in
Figure 2, each end being loaded with a weight.
The mass of this weight and the diameter of pulleys A and B are given in
...
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