1. MMS Technical Bulletin #6
Copper Clad Aluminium Data Category Cables
MMS TB#6 www.prysmiangroup.com
TB6_CCA_nm
Version 1 | 01.06.2015
Page 1 of 5
Introduction
The term Category Cabling sets out the performance of data and communications cabling systems
as defined in ISO/IEC11801. In Europe the equivalent requirements are set out in the EN 50173
series
It has now become apparent that there is a need to clarify the position with regard to cables that
are designed and manufactured specifically to meet the European market for structured cabling as
defined in the EN 50173 series requiring cables to the EN50288 series of standards to other
‘similar’ cables that may be marketed and promoted for ‘category’ applications but do not comply
with the requirements of EN 50288 series. Many users and installers are unaware of the subtle
but important differences between cables complying with the EN 50288 series and those that do
not.
The implications of using non-compliant cables that often claim to be “Category 5” or “Category
5e” but sometimes use conductor materials for example Copper Clad Aluminium (CCA). or
combinations of conductor materials that are not compliant with the requirements given in the
standard for these cable i.e. EN 50288 as pure copper conductors are required.
The reader is referred to ISO/IEC11801, EN50173 and ANSI/TIA568 cabling guide lines. These
specify the requirements and test methods for Communication Cable (and other components)
when installed in buildings or Outside Plant. They also give clear recommendations to the
performance level required by the components (cable) prior to installation.
ISO/IEC 14763-2 and EN50174-2 recommends installation methods provide guidelines for
ensuring that the cable installation will perform to the requirements defined in the standards.
Designers, procurement, installers and users of category cable for ISO/IEC11801 and EN 50173
structured cabling installations should be aware of the problems that appear when using wire that
is not copper in Category Cabling
The information and warnings given in this TB relate to typical applications and installation
practices for copper conductor data cabling in buildings according to the EN 50173
(ISO/IEC11801). This TB also includes an assessment of the hazards presented in specific
installations scenarios where CCA and other non-standard cables may or might be considered to
be installed.
There is no attempt in this TB to mitigate any hazards or give assurance or advice regarding
possible installations where CCA type cable may be suitable. As non-standard products, they
cannot claim any Category!
The fundamental message contained in this TB is to convey the dangers and performance
shortfalls of using cable that is not manufactured to the required standard albeit and never the
less may be marketed suitable for structure cabling systems.
An installed cable that does not meet the specified cable standards cannot be
guaranteed to perform to the system standards required and could be unsafe.

2. MMS Technical Bulletin #6
Copper Clad Aluminium Data Category Cables
MMS TB#6 www.prysmiangroup.com
TB6_CCA_nm
Version 1 | 01.06.2015
Page 2 of 5
Conductors for Data Cables
Copper vs Aluminium
Standards
All standards for Data Cables, whether in CENELEC, IEC, ISO or ANSI, specify requirements
and tests for copper conductors. The mechanical strength, purity and resistance of the
copper are key elements of the requirements needed for the cable to reliably perform
within the applications intended. On the other hand Energy cables have similar standards
but the purity is less than “communications cable” grade copper. This type of copper is not
suitable for use in data cables. There are no specifications for an aluminium conductor
Data Communication Cable, moreover aluminium is not graded product and has very
different electrical characteristics and much lower, mechanical strength and durability. .
There are no standards for Aluminium conductor data cables as they would inevitably have
lesser limits, especially in flexibility, resistance, strength and bending. The following
characteristics and tests are considered important when choosing the type of conductor
acceptable for data cables:
i) Circular (shape)
ii) Resistance
iii) Mass of copper (purity)
iv) Wrapping
v) Elongation
vi) Tensile strength
vii) Oxidisation (shiny and bright)
viii) Overall dimension
Aluminium conductors are not suitable for data cables as they do not meet any of the above
requirements to the same level required; for example the diameter would need to be much larger
so it is not a practical proposition. In addition an installer would have to take these factors into
consideration over its lifetime if it was decided to use Aluminium conductor data cable into a
system.
Conductors; points of weakness to consider
If it is considered that a non-standardised conductor and in particular copper covered
aluminium (CCA) might be used the following should be clearly noted:
i) It could fail basic transmission performance tests during commissioning acceptance
tests
ii) It could exhibit poor flexibility leading to failed connections during both installation
and operation

3. MMS Technical Bulletin #6
Copper Clad Aluminium Data Category Cables
MMS TB#6 www.prysmiangroup.com
TB6_CCA_nm
Version 1 | 01.06.2015
Page 3 of 5
iii) It could produce higher than expected temperature rises when used to provide
power using applications such as Power over the Ethernet
iv) It could exhibit oxidation of exposed aluminium at points of connection which may
reduce lifetime of those connections, particularly when they are subject to vibration
or other movement.
v) Disconnections likely every time the cable is moved behind the patch panel during
maintenance
vi) The IDC or punch downs are likely to fail making installation time longer
vii) Extra lengths of cable may be required at first stage installation in case of re-
terminating after breakages
viii) It may result in re-termination and installation call outs to replace/fix failures
Typical CCA conductors generally have a central aluminium core of between 60% and 80%
of the conductor diameter with the remaining 20% - 40% being a copper cladding
surrounding the aluminium.
Some of the non-data cabling applications (such as coaxial cables) do use CCA to reduce
weight and cost of the cable. Aluminium is a less efficient conductor than copper, but the
higher frequencies associated with data transmission is carried within the copper cladding -
acting as the “skin” of the conductor. In such cases the transmission performance is
provided by the copper, ignoring the aluminium carrier beneath its surface.
Theory might suggest, this should provide a CCA-based balanced pair cable with the high
frequency performance of a given Category at a lower cost however, it is not high frequency
performance that is the principal difficulty but it is at the lower frequency end where the use
of aluminium degrades the performance of the solid copper Category 5/5e cables.
NOTE:
The resistivity of annealed copper is 1,72 x 10-8
Ω.m whereas the resistivity of aluminium is 2,82
x 10-8
Ω.m. The resistance of an aluminium conductor is therefore 64% higher than that of copper
conductor of equal cross-sectional area. A composite CCA conductor has resistance approximately
40% more than the copper equivalent.
The DC loop resistance is a requirement for compliance with:
 Category 5e, 6 or 6A requirements of permanent links and channels in accordance with
ANSI/TIA-568-C.2;
 Class D, E, EA, F and FA requirements of permanent links and channels in accordance with
both ISO/IEC 11801 and EN 50173-1.
In both cases the limits are the same i.e. 25 Ω for channels, 21 Ω for permanent links.

4. MMS Technical Bulletin #6
Copper Clad Aluminium Data Category Cables
MMS TB#6 www.prysmiangroup.com
TB6_CCA_nm
Version 1 | 01.06.2015
Page 4 of 5
If the resistance of CCA conductors is 40% higher than that of solid copper the permanent links
will be noncompliant for lengths in excess of approximately 65m. If the resistance is lower than
40%, the distance at which non-compliance occurs will be longer.
All lengths would fail to comply with the Class requirements in both ISO/IEC 11801 and EN
50173-1 as the actual requirements are length-based on the assumption of 0,19 Ω per metre for
the installation cable plus connections. It should be noted however that most test equipment do
not assess against length-based calculated limits.
Power over Ethernet and other power distribution applications
The latest standard for Power over Ethernet IEEE 802.3at (sometimes termed PoEplus)
increased the current per conductor to 300 mA, which is the current advice from the
standards bodies responsible for ANSI/TIA-568-C.2 and ISO/IEC 11801.
Clearly if the resistance of those conductors is increased as is the case with CCA, the
thermal impact is greater. This exacerbates concerns already being discussed about the use
of balanced cables to support currents in excess of these figures. It is clear CCA will
overheat, and quite quickly when using used for PoE. For a given applied current, initial
temperature increases can be twice those seen on a solid copper conductor. When the cable
starts to overheat positive feedback (spiralling of temperature) begins and unless the
current is switched off permanent changes occur in the cable to the point where it is not
possible to go back to a point of safe working. This could cause extensive damage to
adjacent cables.
The impact of oxidation
Aluminium starts to oxidize as soon as it is exposed to the air – typically when insulation
displacement connections (IDC) are employed to terminate the conductor either in plug or
the socket connections. The contact performance of the oxidised area will quickly deteriorate
causing hot spots. Some countries have already banned the use of aluminium in energy
cables due to the major issues with connectors and oxidation causing fires. The mechanical
performance of the oxidised area will also be affected which can cause the CCA to snap off
when subject to vibration or minor displacement. Repair of such defects frequently requires
the movement of adjacent terminations resulting in further damage in a “pack-of-cards”
sequence. The operational downtime can become prohibitive for the user - and maintaining
these installations can be very costly for an installer.

5. MMS Technical Bulletin #6
Copper Clad Aluminium Data Category Cables
MMS TB#6 www.prysmiangroup.com
TB6_CCA_nm
Version 1 | 01.06.2015
Page 5 of 5
Marking and Directives
A label, box print or cable printing declares that the Cable is e.g. “Category 5” then that should be
expected as to what standard the cable was manufactured to. Unlike some marketing practices
the use of the word “Category” on the label, box print or cable print legend is standardised so it
automatically means that the cable meets Cat x. EN50173 and ISO/IEC 11801 uses this
“Category” to describe limits the cable shall meet. ANSI/TIA goes one step further and uses the
actual abbreviation “Cat” as well as “Category” to indicate that the cable is a data cable
manufactured to a set of limits as determined by the same standard. To disguise this to imply that
the cable is the same as a data cable “type” design but uses CCA, is an attempt to sell a product
that is not fit for the purpose intended.
Within Europe the use of EN Standards allows the product to be “CE” marked. CE marking is
essential to borderless trade between all European countries and imported product. A “CE” mark
can only be placed on a product if it meets an EN standard (or an equal National Standard that
defines all the factors necessary in an EN) or has had a “Technical Document” written up that
defines all the tests necessary to show the product is safe. CCA data cable does not have any
standards, for this reason any importer or manufacturer does have to declare a full technical
document that shows all the testing the design was put through to indicate compliance.
It is illegal to mark a product with a “CE” mark if it does not comply with the CE requirements.
The CE Mark also indicates that the product meets all the EU Directives that would be attributed to
that component. A counterfeit or sub-standard product that is a disguised non-compliance product
would probably fail other important safety requirements.
Conclusion — many of the risks of installing CCA data cables as given in this document above are
of critical importance both to the safe and continued satisfactory performance of the product
within their designed applications. The likelihood of CCA cables some of which may be
counterfeit are more often than not designed to mislead the purchaser, installer and the
eventually the owner of the installation. Their use could very well endanger someone’s life.
European Standards and in particular CE marking, are there to prevent anyone from getting hurt
or killed whether it be super high voltage energy cables or little data cables, the overall result can
still be the same.
© PRYSMIAN GROUP 2015, All Rights Reserved
All sizes and values without tolerances are reference values. Specifications are for product as supplied by Prysmian Group: any
modification or alteration afterwards of product may give different result.
The information contained within this document must not be copied, reprinted or reproduced in any form, either wholly or in part, without
the written consent of Prysmian Group. The information is believed to be correct at the time of issue. Prysmian Group reserves the right to
amend this specification without prior notice. This specification is not contractually valid unless specifically authorised by Prysmian Group.