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Nexans – Pioneers of long-life cables
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In the 1960s when the first crosslinked polyethylene (XLPE) insulated medium voltage (MV) cables were installed, industry expected them to perform reliably for 20-30 years.

History shows that the service life of some of these early cables failed after only 10-15 years due to defects from voltage stress, moisture and other imperfections within the cable structure. It has been estimated that for every dollar that utilities spent installing cable, they had to spend at least 10 dollars to replace it, with some still dealing with this today.

Nexans has an impressively long history as a pioneer in the design and manufacture of quality MV cables in New Zealand. They are the largest power cable manufacturer in NZ and have a state of the art facility in New Plymouth, established in 1967 under CANZAC. The company prides itself on delivering MV cable that has a life expectancy in excess of 50 years.

They know their cable

Nexans (then CANZAC) was the first to manufacture XLPE cables in the Southern Hemisphere in 1967. In 1973, the company were again one of the first in the Southern Hemisphere to introduce extruded semi-conductive screens to replace the taped version, maintaining a uniformly electric field to improve performance. By 1990, the company (then known as Olex Cables) had upgraded from steam to a dry-cured triple extrusion process and introduced tree-retardant cross-linked polyethylene (TR-XLPE) to New Zealand.

The company’s technical experts have been with them from the start, and their experience is what you can trust when it comes to long-life cables. Collaborating with their compound suppliers for over 50 years, Nexans provides the best TR-XLPE material available on the market today. They have thorough standards for their other raw materials as well.

If you’ve ever considered why some cable products are so much cheaper than others, it’s mostly because of the raw materials. The high grade materials that Nexans use make up the majority of the cost of their products, so if the price of other cable looks too good to be true, it almost certainly is.

Indicative Cost Comparison

Constructing Long-Life Cable

A - Using the highest grades of copper and aluminium and the latest stranding technology, the company manufactures over 2 million metres of compacted MV conductors per year.

B - Utilising their state of the art triple extrusion line, raw materials are conveyed from a pressurised clean room to ensure the extruded compounds are free from voids and contaminants. The 3-layer insulated core is monitored in-line, using x-ray technology, to measure key parameters such as wall thickness and concentricity.

C - Expertly controlled metallic screening and cabling processes ensure the cable meets individual customers’ various fault rating requirements.

D - Sheathing layers are applied on thermoplastic extrusion lines where electronic diameter controllers again provide highly accurate in-process control.

Testing Long-Life Cable

Nexans’ test procedures, highly experienced team and specialised equipment all combine to ensure that applicable AS/NZS standards are met. Investing in Nexans cable gives you the very best of design, materials, refined manufacturing processes and quality test systems.

During manufacturing, Nexans carry out comprehensive in-process tests in their IANZ accredited laboratory. This ensures the cable meets the critical requirements of construction from the core through to the final outer sheath.

Once the cable’s completed, Nexans perform electrical tests* such as a spark test on the sheath, conductor resistance, high voltage a.c. and partial discharge (PD).

*A comprehensive list of Nexans’ sample and type tests is available on request.

Evolution of Long-Life Cable

1967 - CANZAC Cables produce the first-generation cross-linked polyethylene (XLPE) cable in the Southern Hemisphere.

1973 - CANZAC is again the first in the Southern Hemisphere to bring in extruded semi-conductive screens/shields to replace the taped version.

1990 - Olex Cables upgrades from steam to dry-cured triple extrusion and introduces the first generation tree-retardant cross-linked polyethylene (TR-XLPE) in New Zealand.

1998 - An X-ray 8000 dimensional controller is installed to the MV line. This scans through three layers of polymer to accurately measure layer thicknesses for consistency.

2005 - Olex Cables goes into full production of the second-generation TR-XLPE reducing tree growth even further. A new advanced high tech X-ray is installed.

2017 - Nexans Olex trials the next generation of TR-XLPE in 2011 and goes into full production in 2017, making Nexans NZ leaders in long-life cable

There are no shortcuts in the manufacturing process at Nexans. With strict adherence to the highest production values and global policies at the forefront, their testing requires special equipment to ensure AS/NZS standards are not only met but, in many cases, exceed expectations, making Nexans reliable suppliers of quality long-life cable.

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