Electrical Connection Summer 2016

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42 E L EC TR I C AL CONNEC T I ON SUMME R 20 1 6
ADVERTORIAL
TAKECAREWHENLAYINGPVCCABLE
P VC insulating and sheath
compounds for cables are
formulated to give excellent
mechanical and electrical properties
for the duration of service life.
Modern PVC plastic formulations
use resins, plasticisers, antioxidants,
stabilisers and fillers to achieve
characteristics such as flexibility,
thermal stability and mechanical and
electrical protection in accordance
with Australian cable standards..
PVC compounds are thermally
stable for the operating temperatures
encountered in typical installation
conditions, when installed in
accordance with AS/NZS 3000.
Certain groups of plasticisers used
in PVC compounds are soluble in
aromatic polymers and petroleum
based products. When in direct
contact with such materials (e.g.
styrene, Styrofoam, polyurethane
and bituminised papers) PVC
compounds can demonstrate
plasticiser migration. This migration
can result in;
1. The loss of physical and
electrical protection afforded by the
insulation and sheath components
of the cable, leading to potentially
dangerous situations.
2. Degradation of the material
which the cable is in contact with.
The breakdown effect of migration
is mainly long term but can be
exacerbated by the size of the
surface contact area and elevated
temperatures such as found in
roof sheeting.
RECOMMENDED INSTALLATION
PRACTICES:
It is recommended that installers
ensure general market PVC insulated
and sheathed electrical cables be
installed in such a manner that
they do not come in to direct
contact with aromatic polymers
(e.g. styrene, Styrofoam and
polyurethane), bituminised papers
and waterproofing. Cables should
be installed in suitable conduits or
protected by the use of polyester
or polypropylene separation tapes.
Alternative PVC cables using
nonmigratory plasticisers are
available, installers should ensure any
such cables sourced can demonstrate
suitable long term test results to
substantiate performance.
Prysmian recommends the use of
Afumex sheathed cables for these
installation types. These cables
have insulation and sheaths that
do not contain PVC (plasticisers)
and therefore do not exhibit the
associated migration issues. Afumex
cables are low smoke zero halogen
types complying with AS/NZS 4507
classification RHE-1.
Please contact Prysmian Cables for
further information.
> Prysmian Group
PVC CABLES IN CONTACT
WITH STYRENE (STYROFOAM),
POLYURETHANE AND
BITUMINISED WATERPROOFING
AND TAPES USED IN
DOMESTIC AND COMMERCIAL
BUILDING APPLICATIONS.
Alternative PVC cables using non-migratory plasticisers can be used to limit
plasticiser migration.
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