What is a Polymeric Cable?

Polymeric cables represent a significant component of Australia’s electrical infrastructure, encompassing a range of cables that utilise polymer-based materials for insulation and protection. These cables form the backbone of electrical distribution systems across residential, commercial, and industrial applications throughout the country. Their use is governed by stringent Australian standards that ensure safety, reliability, and performance in various environmental conditions.

Polymeric cables are defined by their use of polymer-based insulation materials, commonly described as “plastic” or “rubber” or by their specific polymer name. In the Australian context, these cables typically feature conductors (usually copper) encased in polymeric insulating materials that provide electrical isolation, mechanical protection, and environmental resistance. The term “polymeric” refers specifically to the insulation material rather than the conductor itself.

The most common polymeric insulation materials used in Australian electrical cables include:

XLPE is a thermosetting polymer widely used for medium to high voltage cable insulation. The cross-linking process improves the material’s heat resistance, mechanical strength, and electrical properties. Australian standards specifically address XLPE insulated cables for fixed installations for electricity supply at working voltages from 1.9/3.3 (3.6) kV up to and including 19/33 (36) kV. XLPE insulation offers excellent electrical properties, thermal stability, and resistance to environmental factors, making it ideal for underground and overhead power distribution systems.

EPR is another common polymeric insulation material used in Australian electrical cables, particularly in medium and high voltage applications. Like XLPE, EPR-insulated cables are covered under AS/NZS 1429.1:2006, which specifies requirements for these cables when used in fixed installations for electricity supply. EPR offers good flexibility, excellent electrical properties, and resistance to heat, making it suitable for various applications including industrial environments.

PVC is widely used for cable insulation and sheathing in lower voltage applications. The material must comply with Australian safety standards to ensure it doesn’t deteriorate prematurely. In 2015, certain SKL brand electrical cables using PVC insulation were prohibited in Queensland because the PVC material used was not a suitable compound and did not comply with Australian safety standards. This highlights the importance of compliance with standards for polymeric cable materials in Australia.

Australia has developed comprehensive standards that regulate the design, manufacturing, testing, and application of polymeric cables. These standards ensure that cables meet safety and performance requirements appropriate for their intended use:

This standard specifies requirements for XLPE and EPR insulated cables for fixed installations for electricity supply at working voltages from 1.9/3.3 (3.6) kV up to and including 19/33 (36) kV. It covers aspects such as construction, dimensions, electrical properties, and testing procedures. This standard is particularly important for medium voltage distribution cables used by utilities and in industrial applications.

This standard covers polymeric insulated electric cables for working voltages up to and including 0.6/1 (1.2) kV. It specifies construction, dimensions, and test requirements for single and multicore cables insulated with polymeric materials intended for use in electrical installations at lower voltages. It does not apply to polymeric insulated cables for special installations and service conditions for which there are separate Australian/New Zealand Standards.

This standard addresses polymeric insulated electric cables for distribution and service applications. It provides specifications for a range of single core XLPE insulated distribution and service cables, ensuring they meet the necessary requirements for safe and reliable operation in Australian conditions.

While not directly about polymeric cables themselves, this standard specifies requirements for polymeric cable protection covers, which are an important part of underground cable infrastructure. These covers provide mechanical protection and visual warning for underground cable systems. They play a crucial role in preventing accidental damage to buried cables during excavation activities.

Polymeric cables find widespread use across various sectors in Australia, serving critical infrastructure needs:

Polymeric cables, particularly those insulated with XLPE and EPR, are extensively used in Australia’s power distribution networks. They form the backbone of urban and rural electrical infrastructure, enabling the reliable transmission of power from substations to end-users. These cables are designed to operate reliably in Australia’s challenging environmental conditions, including high temperatures, UV exposure, and varying soil conditions for underground installations.

With Australia’s growing renewable energy sector, polymeric cables play a crucial role in wind farm development, solar farms, and other renewable energy infrastructure. The cables connect generation equipment to distribution networks and must withstand specific environmental challenges associated with these installations, including extended outdoor exposure and mechanical stress.

Polymeric cables are used extensively in Australia’s mining and resources sector, including coal seam gas projects and other resource extraction operations. These applications often require cables with enhanced mechanical protection, chemical resistance, and reliability in harsh environments.

In the building sector, polymeric cables are commonly used for internal wiring and service connections. Since January 29, 2018, building wiring cables have been deemed declared electrical articles in New South Wales, requiring compliance testing prior to sale. This regulation ensures that all polymeric cables used in buildings meet appropriate safety standards.

Australia’s rail systems utilise specialised polymeric cables for various applications, including traction power and signaling systems. These cables must meet specific requirements for reliability, durability, and safety in transportation applications.

Polymeric cables represent a critical component of Australia’s electrical infrastructure, providing safe and reliable power distribution across various sectors. The comprehensive standards framework established in Australia ensures these cables meet stringent safety and performance requirements appropriate for their intended applications. As Australia continues to develop its electrical infrastructure, particularly in renewable energy and modernising urban power grids, polymeric cables will continue to play a vital role in ensuring reliable and safe electrical power distribution. Have any questions? Contact the friendly team at Wilken, we’d be glad to help!