Sparks Electrical News July 2018

CABLES AND CABLE ACCESSORIES

14

CABLES FOR MULTIMEDIA APPLICATIONS LEGRAND’S extensive range of cable and ca- ble accessories encompasses multimedia ca- bles, which are designed to fit easily into work areas and in spaces where technology-users need access to power and data connections. These cables are compatible with most desk- top PCs, laptops, monitors, scanners and print- ers, as well as gaming consoles and audio and video equipment. and splitters – send high definition 1080p video, from a DVI enabled device to a display. Cat6 patch cables are used for Ethernet connections. In addition, couplers and cable management products are available from Legrand for extending the signal and organising a network. DisplayPorts are designed for connecting high definition digital audio/video devices to displays. The company also offers solutions for both analogue and digital audio/ video signals

for adding, duplicating or extending a video device. PC connectors make sure a device stays powered and connected to other devices. These connectors adapt with older technology, ensuring all devices work flawlessly. Data connectors are used for Ethernet and Gigabit networks that require fast bandwidth intensive data or for video distribution applications. Legrand’s comprehensive range of products and systems for electrical and digital building infrastructures has been designed for easy installation, high efficiency, optimum safety and enhanced aesthetics – whether original installations, extensions or reconfigurations.

According to Legrand SA, HDMI® is the most popular audio/visual connection for modern- day consumer electronics. The HDMI signal, which is the digital replacement for analogue video standards, carries digital audio and visual resolutions up to 4 k supporting Ultra HD. DVI products – cables, adapters, extenders

Legrand multimedia cables include connectors for audio, video and PC devices and data networks. Audio connectors allow for both analogue and digital signals, whilst video connectors are the perfect solution

Enquiries: +27 (0) 11 444 7971

THE BENEFITS OF USING XLPE LUGS AND FERRULES HELLERMANNTYTON’S SABS approved range of XLPE lugs and fer- rules is designed for single and multi-core XLPE (cross-linked poly- ethylene insulation) cable applications and suitable for use in medium voltage distribution networks such as utilities, power distribution and mining.

cretion of the supplier. Generally this warranty does not cover batteries, neglect or misuse within abnormal conditions of operation. Regular servicing is recommended as a faulty tool is dangerous, and costly if you need to replace it. It will also take time to organise collection and delivery of replacement tooling, leading to increased time on site and a reduction in productivity, which could have a ripple effect down the line if essential work is reliant on the crimping or cutting of cables.

• Over-crimping damages a lug and therefore limits the standard lug’s lifetime performance. • Standard lugs and ferrules have an inspection window and there- fore allow water ingress. The benefits of using a hydraulic crimper Whether you are buying or hiring an hydraulic cable crimper or cut- ter, following these guidelines helps prevent more than just tool fail- ure and time lost on site. An example of this is incorrect crimping, which can lead to a number of issues with lug failure. If the tool is unable to properly crimp the lug to the cable, air pockets within the core can cause an increase in resistance leading to overheating and potentially a fire. Typically, hydraulic tools are naturally robust given the nature of the tasks they are designed for. However, it is recommended that your tools are serviced and calibrated regularly. Also, the on-site team is reminded about the importance of pre-use checks and tests, as well as the dangers associated if a crimp is not undertaken carefully and correctly. When you hire or purchase a tool you should also check its condition as soon as you receive it, making sure there are no defects that could impact performance. Usually, tools distributed from reputable companies are calibrated, tested and guaranteed before delivery. However, checking yourself should be the final line of defence. It is recommended you get your hydraulic tool calibrated and serviced every 12 months. Calibration will test the pressure of your tool using a manometer. The pressure measurement test will ensure the tool meets the recommended level of pressure to enable the correct crimping or cutting operation. If the tool does not meet the required minimum pres- sure, it needs to be sent to the manufacturer for service or repair. If the tool is still under warranty, it will either be repaired or replaced at the dis- KEI manufactures HT XLPE cables up to 220 kV conforming to Na- tional and International Standards at its Bhiwadi high voltage ca- ble plant in India. Supplied locally by Consortium Cables, KEI has CCV (Continuous Catenary Vulcanising) lines with a single point tri- ple extrusion and sophisticated computerised control with monitor- ing systems. The CCV line was imported from Machinenbau Scholz, GMBH & Co KG, a pioneer in this technology having supplied more than 250 lines throughout the world. The plant is designed to produce high tension power cables and high voltage cables as well as high tension cables for heavy duty ma- chines. It has heavy duty machines for wire drawing and conductor making, laying up, armouring, sheathing and packing. Making high tension cables As a reputable high tension cable manufacturer the process of mak- ing the best high tension cables, whether medium voltage or high voltage cables, is carefully monitored. It commences with a com- pacted circular conductor being fed from the pay off stands into the extruder, on an elevated platform. The conductor passes through the extruder’s crosshead; it is covered first with a semiconducting screen layer then the XLPE insulation, followed by the outer semiconduct- ing core screen. This crosshead is specially designed to feed three compounds from three extruders at one point, described as Singe Point Triple Extrusion. Thereafter, the extruded core enters and passes through the vul- canising line, known as the CCV line, and the XLPE insulated core is cured in the process. In the CCV line, inert atmosphere is maintained

In general, lugs and ferrules are fixed to the cables and wires by insert- ing the conductor/s into the ‘barrel’ (tube) of the device and then ‘crimp- ing’ (squeezing) the barrel onto the conductor/s to form a secure me- chanical and electrical joint. In order to achieve this secure mechanical and electrical joint, the right lug or ferrule needs to be selected according to the cable used and the area of application. Why use an XLPE lug and XLPE ferrule with XLPE cable? • XLPE cable is a compacted cable, resulting in smaller core sizes than standard cable. • The internal diameters of XLPE lugs and ferrules are smaller than standard lugs and ferrules to fit the XLPE core size and to prevent over-crimping. • XLPE cables are used mainly in distribution networks to prevent moisture ingress. • XLPE lugs have no inspection window, which aids the sealing of the cable end. • XLPE lugs have a thicker wall, improving the crimp and therefore better heat dissipation (no hot joints). • SABS approved (SANS IEC 61238-1:2003) lugs and ferrules. Why standard lugs and ferrules should not be used on XLPE cables • Standard lugs and ferrules need to be over-crimped or double crimped, which can cause hot spots and the lug to fail or burn-off.

Enquiries: www.hellermanntyton.co.za

STATE-OF-THE-ART HIGH VOLTAGE CABLES

by Nitrogen gas, which is maintained at high pressures and a high temperature. The process is popularly known as the single point triple extrusion CDCC (Completely Dry Cured and Cooled Curing) Process. For the cured core, a copper screening is provided by the lapping of a copper tape or, for special requirements, a layer of copper wire is provided. The core is tested for partial discharge and then, as per requirements, the cores are laid up with fillers, provided with an inner sheath, ar- moured and sheathed. The sheath can made of PVC, HDPE, FRLS, ZHFR, PCP or CSP compounds. A strict quality plan and fully equipped test lab ensure the high voltage cables are of the best quality and are produced as per the design and specifications prescribed. These high voltage electrical cables and other medium voltage cables have been type tested as per international standards at international labs.

Inventory and production plans are controlled by the BANN ERP system. This ensures reliable and prompt delivery with operational efficiency for all high voltage ca- bles and other products produced. KEI applied successfully to the SABS for its XLPE insulated cables for rated voltages 3,8/6,6 kV to 19/33 kV (code 1339:2015).

Enquiries: +27 (0) 11 894 4538

SPARKS ELECTRICAL NEWS

JULY 2018