IEC 61196-1-111:2024

IEC 61196-1-111 ®
Edition 3.0 2024-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Coaxial communication cables –
Part 1-111: Electrical test methods – Stability of phase test methods

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IEC 61196-1-111 ®
Edition 3.0 2024-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Coaxial communication cables –
Part 1-111: Electrical test methods – Stability of phase test methods
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.10 ISBN 978-2-8322-9755-1
– 2 – IEC 61196-1-111:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Phase variation with temperature . 9
4.1 Purpose . 9
4.2 Test equipment . 9
4.3 Preparation of test sample (TS) . 9
4.4 Test environment . 10
4.5 Preconditioning . 10
4.6 Test procedure . 10
4.7 Test result. 12
4.7.1 Calculation of temperature coefficient of phase. 12
4.7.2 Graph of phase temperature change . 13
4.7.3 Maximum variation value of phase variation with temperature . 13
4.7.4 Ratio of the relative phase temperature coefficient . 13
4.8 Test report . 13
4.9 Requirement . 13
5 Phase constant variation with temperature . 13
5.1 Purpose . 13
5.2 Test equipment . 14
5.3 Test sample . 14
5.4 Test environment . 14
5.5 Preconditioning . 14
5.6 Test procedure . 14
5.7 Test result. 14
5.8 Test report . 15
5.9 Requirement . 15
6 Phase stability with bending . 15
6.1 Purpose . 15
6.2 Test environment . 15
6.3 Test sample . 16
6.4 Test equipment . 16
6.5 Test procedure . 16
6.6 Test report . 17
6.7 Requirement . 18
7 Phase stability with twisting . 18
7.1 Purpose . 18
7.2 Test environment . 18
7.3 Test sample . 18
7.4 Test equipment . 19
7.5 Test procedure . 19
7.6 Test report . 20
7.7 Requirement . 20
Annex A (normative) Phase consistency test for two or more cables . 21
A.1 Purpose . 21

A.2 Test equipment . 21
A.3 The preparation of test sample (TS) . 21
A.4 Test environment . 21
A.5 Test procedure . 22
A.6 Test report . 22
A.7 Requirement . 22
Annex B (normative) Phase variation with temperature test between two cables . 23
B.1 Purpose . 23
B.2 Preparation of test sample . 23
B.3 Test environment . 23
B.4 Preconditioning . 23
B.5 Test procedure . 23
B.6 Test results . 23
B.7 Test report . 24
B.8 Requirement . 24
Annex C (informative) Example for recording and calculating the phase variation with
temperature . 25
C.1 Purpose . 25
C.2 Test sample . 25
C.3 Test conditions . 25
C.4 Test record and calculation . 25
C.5 Test result calculation . 26

Figure 1 – Test sample (TS) . 9
Figure 2 – Preconditioning . 10
Figure 3 – TS placement diagram . 11
Figure 4 – Phase–Frequency graph schematic diagram . 12
Figure 5 – Test sample (TS) . 16
Figure 6 – Bending test . 17
Figure 7 – Test graph schematic diagram . 18
Figure 8 – Twist test . 19
Figure 9 – Test graph schematic diagram . 20
Figure A.1 – Cable . 21
Figure A.2 – Cable assembly (TS) . 21
Figure B.1 – η − T (°C) contrast graph . 23
tf,
η −
Figure C.1 – T (°C) graph . 26
tf,
Table C.1 – Test record and calculation . 26

– 4 – IEC 61196-1-111:2024 RLV © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COAXIAL COMMUNICATION CABLES –

Part 1-111: Electrical test methods – Stability of phase test methods

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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6) All users should ensure that they have the latest edition of this publication.
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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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 61196-1-111:2014. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
IEC 61196-1-111 has been prepared by subcommittee 46A: Coaxial cables, of IEC technical
committee 46: Cables, wires, waveguides, RF connectors, RF and microwave passive
components and accessories. It is an International Standard.
This second edition cancels and replaces the first edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) addition of the list of test methods in the Scope;
b) addition of "the number of scanning points" in every test method;
c) addition of Annex A, Phase consistency test for two or more cables;
d) addition of Annex B, Phase variation with temperature test between two cables.
The text of this International Standard is based on the following documents:
Draft Report on voting
46A/1666/CDV 46A/1680/RVC
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.
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/publications.
A list of all parts in the IEC 61196 series, published under the general title Coaxial
communication cables, 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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.

– 6 – IEC 61196-1-111:2024 RLV © IEC 2024
COAXIAL COMMUNICATION CABLES –

Part 1-111: Electrical test methods – Stability of phase test methods

1 Scope
This part of IEC 61196 applies to coaxial communication cables. It specifies methods for
determining the stability of phase of coaxial communication cables.
This part of IEC 61196 provides test methods to determine the stability of phase of coaxial
communication cables.
This document is applicable to RF coaxial cables. RF coaxial cable assemblies can also use
this document for reference.
This part of IEC 61196 comprises following test methods:
a) phase variation with temperature (Clause 4);
b) phase constant variation with temperature (Clause 5);
c) phase stability with bending (Clause 6);
d) phase stability with twisting (Clause 7);
e) phase consistency test for two or more cables (Annex A);
f) phase variation with temperature test between two cables (Annex B).
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 61196-1, Coaxial communication cables – Part 1: Generic specification – General,
definitions and requirements
IEC 61196-1-108:2011, Coaxial communication cables – Part 1-108: Electrical test methods –
Test for characteristic impedance, phase and group delay, electrical length and propagation
velocity
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61196-1 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp

3.1
temperature coefficient of phase
η
tf,
coefficient defined as at the specified frequency f, as the ratio of the phase difference Δφ
tf,
φ φ Φ
between at 25 °C and at temperature t, and the total phase at 25 °C
25 °C,f tf, 25 °C,f
φ −φ Δφ
25 °C,f tf, tf,
η
(1)
tf,
ΦΦ
25 °°C,ff25 C,
where:
φ is the phase at temperature t and frequency f, in (°);
tf,
φ
is the phase at 25 °C and frequency f, in (°);
25 °C,f
Δφ is the phase difference between φ and φ at frequency f, in (°);
tf, 25 °C,f tf,
Φ is the total phase at 25 °C and frequency f, in (°)
25 °C,f
3.2
maximum variation of temperature coefficient of phase
Δη
max
maximum value η minus the minimum value η
max min
Δη η −η
(2)
max max min
3.3
ratio of relative temperature coefficient of phase PT
ratio of the relative temperature coefficient of phase PT, when the relationship between phase
and temperature is sufficiently linear
φφ−
tf,,t f
PT = (3)
Φ ×−tt
( )
25 °C,f 2 1
where:
φ  is the phase value at t and frequency f, in (°);
tf1, 1
φ
is the phase value at t and frequency f, in (°);
t2,f
Φ is the total phase at 25 °C and frequency f, in (°);
25°C,f
t and t are any two temperatures within a specified temperature range in which the relationship
1 2
between phase and temperature is sufficiently linear (t > t ), in °C
2 1
=
==
– 8 – IEC 61196-1-111:2024 RLV © IEC 2024
3.4
total relative variation of phase constant
total relative variation of the phase constant
ββ−
δβ =
(4)
β
nom
ll−
ee,2 ,1
δβ × ν τ −τ ××c ν
(5)
( )
r,nom pp,2 ,1 r,nom
l
mech
where:
is the phase constant at temperature t , in radians/m;
β
1 1
is the phase constant at temperature t > t , in radians/m;
β
2 2 1
is the nominal phase constant, in radians/m;
β
nom
τ
is the phase delay at temperature t , in s/m;
p,1
τ is the phase delay at temperature t > t , in s/m;
p,2 2 1
c is the propagation velocity in free space (3 × 10 m/s);
l
is the electrical length at temperature t , in m;
e,1
l is the electrical length at temperature t > t , in m;
e,2 2 1
l is the mechanical length, in m;
mech
ν is the nominal relative propagation velocity
r,nom
Note 1 to entry: For unidirectional variation, t and t are the limits of a specified temperature range. In the case of
1 2
changing signs of variation, t and t become the temperatures at which the extreme value of l or τ occur.
1 2 e p
3.5
temperature coefficient of phase constant, CT
temperature coefficient of the phase constant
δβ
CT =
(6)
tt−
where:
-1
CT is the temperature coefficient of phase constant, in K ;
δβ is the total relative variation of the phase constant;
= =
t and t are any two temperatures within a specified range in which the phase constant is
1 2
approximately linear, in °C
4 Phase variation with temperature
4.1 Purpose
Phase of cable varies as a function of temperature. The temperature variation will induce the
change of the dielectric constant ε , mechanical length, and material character which will
r
cause its phase variation. This variation can be unidirectional or multi-directional. The phase
η
variation is characterized by the temperature coefficient of phase or by the ratio of relative
tf,
i
temperature coefficient of phase PT when the relationship between phase and temperature is
sufficiently linear. This method provides a test method to determine the phase variation with
temperature. The maximum variation of temperature coefficient of phase Δη   is given in
max
Formula (2).
A phase variation with temperature test to determine the difference of phase variation with
temperature between two cables is given in Annex B.
4.2 Test equipment
A temperature chamber with sufficient precision, temperature range and volume shall meet the
requirement specified in the relevant specification (for PTFE insulated cable, the temperature
should be within ±2 °C).
A vector network analyzer (VNA) capable of sufficient precision is recommended.
Test equipment should be as follows:
a) a temperature chamber with sufficient precision within ± 2 °C;
b) a vector network analyser (VNA) with sufficient precision;
c) test clamp for fixation (if needed).
4.3 Preparation of test sample (TS)
The cable under test shall be terminated with suitable connectors at each end to make a cable
assembly as a test sample (TS), as shown in Figure 1. It is suggested that a pair of screw thread
connectors which suit with the vector network analyser should be used to make a TS for
convenience and higher precision. Two marks should be made at each end of the TS, as shown
in Figure 1. L shall not be less than 0,15 m and L of the cable under test-(CUT) shall
1mech 2mech
not be less than 2,70 m.
At least two TS should be made.

Figure 1 – Test sample (TS)
– 10 – IEC 61196-1-111:2024 RLV © IEC 2024
4.4 Test environment
The variation of the laboratory's ambient temperature shall be within ±2 °C. The recommended
temperature is 25 °C. For a cable with PTFE dielectric, the laboratory's ambient temperature
should avoid the material's sensitive temperature interval.
4.5 Preconditioning
The TS shall be put into a temperature chamber in loose coils with the diameter not less than
10 times of the cable's minimum static bending radius.
Adjust the temperature of the chamber for 6 cycles as shown in Figure 2 and maintain at least
30 min at each limit temperature (t and t ) which shall be specified in the relevant
max min
specification to ensure temperature balance inside. the number of cycles may be agreed
between the customer and the supplier.

Key
t laboratory's ambient temperature, for example 25 °C ±2 °C;
t maximum temperature specified in the relevant specification, in °C;
max
t minimum temperature specified in the relevant specification, in °C.
min
Figure 2 – Preconditioning
4.6 Test procedure
The test procedure is as follows:
a) after preconditioning, one of the TS is picked up for calibration as a reference sample during
the test. The state and position of the reference sample should not be changed during the
test period to avoid any measurement error.
b) put the other TS into the temperature chamber with two ends of the TS from the marks
outside the chamber and seal the chamber with thermal insulating plugs as shown in
Figure 3. The marks in Figure 3 are proposed to be placed in the middle of the thermal
insulating plugs. The other part of the TS in the chamber shall be placed in loose coils with
the diameter not less than 10 times of the cable's minimum static bending radius.

Figure 3 – TS placement diagram
c) After being preheated, the VNA shall be set to S or S with the number of scanning points
12 21
not less than 801. Calibrate it over the specified frequency range.
after the VNA is fully preheated, set the measurement frequency range and the test mode
to S12 or S21. The number of scanning points shall be set according to Formula (7) and
shall not be less than 801. When the value calculated according to Formula (7) exceeds the
maximum number of points of the device, the highest number of points that the VNA can
reach should be taken.
3( f − fl)
n ≥ (7)
where:
n is the number of scanning points of measurement;
f is the lowest point of the frequency range, in MHz;
f is the highest point of the frequency range, in MHz;
l is the physical length of the cable under test, in m.
Set the temperature chamber to 25 °C and maintain at least 10 min when it reaches the
temperature. Connect the TS with the VNA and read the frequencies f and f which are the
1 2
adjacent peak wave or valley wave as shown in Figure 4. The frequencies f and f should
1 2
be near the value of f. The total phase of the CUT at frequency f at 25 °C is:

f L
2mech
Φ 360° × ×
25 °C,f (8)
f − fL
2 1 sample
=
– 12 – IEC 61196-1-111:2024 RLV © IEC 2024

Figure 4 – Phase–Frequency graph schematic diagram
d) at 25 °C, use the reference sample to calibrate VNA, then connect the TS with the VNA and
φ at frequency f. Connect the reference sample with the VNA
record the phase value
25 °C,f
δ
again and record its phase drift
25 °C,f
e) adjust the temperature of the chamber to the lowest temperature t and maintain for enough
time that the CUT becomes balanced in temperature (see NOTE 1). Repeat the steps of 4.6,
φ δ
paragraph 5 and record the phase value and phase drift at test frequency f at t .
tf, 1,f
f) adjust the temperature of the chamber to each higher temperature t (see NOTE 2) until it
i
reaches the maximum temperature of the cable and repeat the steps of 4.6, paragraph 6
φ δ
and record the phase value and phase drift at frequency f at t .
tf, if,
i
i
NOTE 1 Different cables differ in maintaining time. When the outer diameter of cables is less than 6 mm, the
maintaining time is at least 30 minutes or as specified in the relevant specification; when the outer diameter of
cables is more than 6 mm, the maintaining time is increased or as specified in the relevant specification.
NOTE 2 For cables with PTFE dielectric, the testing temperature point between ‒20 °C to 25 °C is increased
so as to get a more accurate result.
4.7 Test result
4.7.1 Calculation of temperature coefficient of phase
Use Formula (1) to calculate the temperature coefficient of phase η at t at frequency f:
tf, i
i
φ −−φ δ / 2 Δφ
25 °C,f tf, i,f tf,
ii
η
(9)
tf,
i
ΦΦ
25 °°C,f 25 C,f
where:
φ
is the phase at 25 °C at frequency f, in (°);
25 °C,f
ϕ
is the phase at t at frequency f, in (°);
tf,
i i
δ is the VNA phase drift at each temperature point during test, in (°);
if,
Φ
is the total phase at 25 °C and frequency f, in (°);
25 °C,f
∆ϕ ϕ ϕ
tf, 25℃, f tf,
i i
is the phase difference between and at frequency f, in (°).

==
The phase drift of the VNA can be ignored when no higher precision is requested, and the
temperature coefficient of phase η at t at frequency f can be calculated with:
tf, i
i
φ −φ Δφ
25 °C,f tf, tf,
ii
η
(10)
tf,
i
Φ Φ
25 °°C,f 25 C,f
4.7.2 Graph of phase temperature change
η ηT−
Use each and t to draw the (°C) curve graph of phase variation with temperature
tf, tf,
i
i
at specified frequency f.
4.7.3 Maximum variation value of phase variation with temperature
Use Formula (2) to calculate maximum variation value of phase variation with temperature
(ηη− ).
max min
4.7.4 Ratio of the relative phase temperature coefficient
Use Formula (3) to calculate the ratio of the relative temperature coefficient of phase PT when
the relationship between phase and temperature is sufficiently linear.
4.8 Test report
The test report shall include information such as the following:
a) the preconditioning temperature (t – t );
max min
b) the temperature range and test temperature points;
c) the maintaining time at each temperature;
d) the sample length;
e) the test frequency.
Annex C gives an example on how to record the testing data and calculate testing result of the
phase variation as temperature change.
4.9 Requirement
The values shall meet the requirements of the relevant specification.
5 Phase constant variation with temperature
5.1 Purpose
Phase constant varies as a function of temperature. This variation can be unidirectional or multi-
directional. The stability of the phase constant is characterized either by the total variation of
the phase constant or by the temperature coefficient of the phase constant in a temperature
range in which the relationship between phase and temperature is sufficiently linear. The phase-
temperature relationship of new cables may be influenced by irreversible variations of the phase
constant. These can be reduced by heat cycling.
A test to determine the phase consistency of two or more cables with the same length and cut
from the same cable or the same batch of cables is given in Annex A.
==
– 14 – IEC 61196-1-111:2024 RLV © IEC 2024
In addition to the temperature, the phase constant depends on the pressure and the humidity
of the gas enclosed within the cable. This is of particular interest in the case of cables with
airtight outer conductors.
5.2 Test equipment
Test equipment is as follows:
a) a temperature chamber with sufficient precision, temperature range and volume shall meet
the requirement in the relevant specification.
b) a vector network analyser (VNA) capable of sufficient precision is recommended.
c) test clamp for fixation should meet the precision requirement (if needed).
5.3 Test sample
Prepare the TS according to 4.3 or the relevant specification.
5.4 Test environment
The variation of the laboratory's ambient temperature shall be within ±2 °C. For cables with
PTFE dielectric, the laboratory's ambient temperature should avoid the material's sensitive
temperature interval.
5.5 Preconditioning
The TS shall be preconditioned according to 4.5.
5.6 Test procedure
The test procedure is as follows:
a) the VNA shall be calibrated according to the error correction procedure given in the manual
of the VNA.
b) put the TS into the temperature chamber with two ends of TS from the marks outside the
chamber and seal the chamber with thermal insulating plugs as shown in Figure 3. The other
parts of the TS in the chamber shall be placed in loose coils with the diameter not less than
10 times of the cable's minimum static bending radius.
Refer to Figure 3 for the placement of TS.
c) set the temperature of chamber to t and maintain 30 min at least when it reaches t .
1 1
Measure the phase φ in radians at t according to IEC 61196-1-108.
tf, 1
d) set the temperature of chamber to t and maintain 30 min at least when it reaches t .
2 2
Measure the phase φ in radians at t according to IEC 61196-1-108.
tf,
5.7 Test result
ββ−
According to Formula (9) of IEC 61196-1-108:2011, is calculated as:
t f t f
2, 1,
φφ
t ,,f tf
ββ−= − (11)
t f t f
2, 1,
LL
2mech 2mech
where:
β is the phase constant at t at frequency f, in radians/m;
t f 1
1,
β  is the phase constant at t at frequency f, in radians/m;
tf 2
2,
φ is the phase at t at frequency f, in radians;
tf, 1
φ is the phase at t at frequency f, in radians.
tf, 2
The total relative variation of the phase constant is:
ββ−
t,f tf,
δβ =
(12)
β
nom, f
where:
β is the phase constant at t at frequency f, in radians/m;
tf, 1
β
is the phase constant at t at frequency f, in radians/m;
tf,
β is the nominal phase constant at frequency f, in radians/m.
nom, f
Use Formula (6) to calculate the temperature coefficient of the phase constant CT.
5.8 Test report
The test report shall include information such as the following:
a) the preconditioning temperature (t – t );
max min
b) the temperature range (t – t );
1 2
c) the maintaining time;
d) the sample length;
e) the test frequency;
f) the nominal phase constant;
g) the temperature coefficient of the phase constant.
5.9 Requirement
The values shall meet the requirements of the relevant specification.
6 Phase stability with bending
6.1 Purpose
The structure and electrical length of the cable will be changed when it is subjected to bending,
which will induce the phase change. This method provides a test method to determine the phase
variation with specified frequency when the cable is subjected to bending.
6.2 Test environment
The variation of the laboratory's ambient temperature shall be within ±2 °C. The recommended
temperature is 25 °C.
– 16 – IEC 61196-1-111:2024 RLV © IEC 2024
6.3 Test sample
The cable under test shall be terminated with suitable connectors at each end, shown in
Figure 5. It is recommended that a pair of screw thread connectors which suit with the vector
network analyser is used to make a test sample for convenience and higher precision, The
length L of the cable under test (CUT) shall meet the requirements shown in Figure 5.

Figure 5 – Test sample (TS)
6.4 Test equipment
Test equipment is as follows:
a) A vector network analyzer (VNA) capable of sufficient precision is recommended.
b) The test clamp for fixation should meet the precision requirement (if needed).
6.5 Test procedure
The test procedure is as follows:
a) After being preheated, the VNA shall be set to S12 or S21 with the number of scanning
points not less than 801 according to 4.6c), Calibrate it over the specified frequency range.
b) Connect the TS with the VNA and bend the CUT to U shape with the minimum bending
radius r specified in relevant specification as shown in Figure 6a). Calibrate the phase of
the VNA to zero.
c) Put a mandrel with the specified diameter d on C and bend the CUT around the mandrel for
180° as shown in Figure 6b). Record curve 1 of the phase variation with frequency in the
VNA shown in Figure 8. Bending should be very carefully performed and stable in order to
reduce its effect on the test result.
d) Straighten CUT back to the initial position shown in Figure 6a). Put the mandrel under the
CUT, and then bend the CUT around the mandrel for 180° in a reversed way as shown in
Figure 6c). Record curve 2 of the phase variation with frequency in the VNA shown in
Figure 8.
a) Initial position
b) First bend
c) Second bend
Figure 6 – Bending test
6.6 Test report
The test report shall include information such as the following:
a) the bending radius r of the U shape; normally r is shall not be less than the minimum
dynamic bending radius;
b) the diameter d of the mandrel, which is usually 10 times of the cable's outer diameter;
c) the test frequency;
d) the result of the test: curve 1 and curve 2.

– 18 – IEC 61196-1-111:2024 RLV © IEC 2024

Figure 7 – Test graph schematic diagram
6.7 Requirement
The result of the test (curve 1 and curve 2) shall meet the requirement in the relevant
specification shown as permit range value in Figure 7.
7 Phase stability with twisting
7.1 Purpose
The structure and electrical length of the cable will be changed when it is subjected to twisting,
which will induce the phase change. This method provides a test method to determine the phase
variation with specified frequency when the cable is subjected to twisting.
7.2 Test environment
The variation of the laboratory's ambient temperature shall be within ±2 °C. The recommended
temperature is 25 °C.
7.3 Test sample
The cable under test shall be terminated with suitable connectors at each end, as shown in
Figure 5. A pair of screw thread connectors which suit with the vector network analyser should
be used to make a test sample for convenience and higher precision. The length L of the cable
under test should be:
360°
L =
(13)
θ
where:
L is the length of CUT, in m;
θ is the permitting maximum twist angle per length specified in the relevant specification, in
°/m.
7.4 Test equipment
Test equipment is as follows:
a) a vector network analyzer (VNA) capable of sufficient precision is recommended.
b) the test clamp for fixation should meet the precision requirement (if needed).
7.5 Test procedure
The test procedure is as follows:
a) After being preheated, the VNA shall be set to S12 or S21 with the number of scanning
points not less than 801 according to 4.6c),Calibrate it over the specified frequency range.
b) Connect the TS with the VNA and bend the CUT to U shape around a mandrel with the
specified diameter d as shown in Figure 8a). Calibrate the phase of the VNA to zero.
c) Rotate the mandrel to 180° as shown in Figure 8b) and record curve 3 of the phase variation
with frequency in the VNA shown in Figure 9. Twisting should be very carefully performed
and stable in order to reduce its effect on the test result.
d) Return the mandrel to the initial position shown in Figure 8a). Then rotate the mandrel to
180° in the reverse way as shown in Figure 8c). Record curve 4 of the phase variation with
frequency in the VNA shown in Figure 9.

a) Initial position
b) First twist
c) Second twist
Figure 8 – Twist test
– 20 – IEC 61196-1-111:2024 RLV © IEC 2024
7.6 Test report
The test report shall include information such as the following:
a) the diameter d of the mandrel, which is usually 10 times of the cable's outer diameter;
b) the test frequency range;
c) the maximum twist angle per length;
d) the result of test: curve 3 and curve 4.

Figure 9 – Test graph schematic diagram
7.7 Requirement
The result of test (curve 3 and curve 4) shall meet the requirements in the relevant specification
shown as permit range value in Figure 9.

Annex A
(normative)
Phase consistency test for two or more cables
A.1 Purpose
The change of cable dielectric constant can cause the phase change. This test is to determine
the phase consistency of two or more cables with same length and cut from a same cable or
same batch of cables in the specified frequency range.
A.2 Test equipment
Test equipment should be as follows:
a) a vector network analyzer (VNA) capable of sufficient precision is recommended.
b) test clamp for fixation (if needed).
A.3 The preparation of test sample (TS)
Cut two or more pieces of cables with same length l from a cable under test (CUT) as shown in
Figure A.1.
Figure A.1 – Cable
Each piece of cable shall be terminated with a suitable pair of connectors with same model and
specification and quality, to make a cable assembly as a test sample (TS), as shown in
Figure A.2.
Figure A.2 – Cable assembly (TS)
It is recommended that a pair of screw thread connectors which suit with the vector network
analyser (VNA) should be used to make a test sample for convenience and higher precision.
To improve the test precision, the difference be
...