Sparks Electrical News November 2017

CABLES AND CABLE ACCESSORIES

14

DRAWING GALVANISED WIRE THROUGH A CONDUIT

T he most important thing to remember about drawing wire, is to keep the end goal in mind. In existing electrical installations, it is often not feasible to lay new conduit for wiring, so it is necessary to run new wire through existing conduit. While there may be many methods of doing this, the most important factor to focus on is getting the wire through the conduit. Another important factor to keep in mind when drawing wire, is to make sure you have the right equipment for the job. Simply put, if you don’t have the right equipment, you will not even be able to get started. As much as we all love

DETECTING UNDERGROUND SERVICES BOSCH MUNITECH’S specialised Underground Services Location (USL) facility encompasses advanced utility detection and mapping services, essential for providing accurate information of buried utility infrastructure layouts. “USL – which requires expert skills, using non- intrusive methods to locate the exact type, size, position and depth of buried utilities – is critical in reducing risk and ensuring efficiency and safety in every excavation or construction project,” says Chris Otto, divisional head: underground services and leak detection, Bosch Munitech, part of Bosch Holdings. “Before digging commences, it is vital that all buried utilities likely to be affected by exca- vation or construction, are located. Underground utilities unexpectedly encountered during excava- tion, could cause costly delays of the project, the disruption of essential services and the injury or death of workers. “Bosch Munitech uses advanced equipment, including electromagnetic locators, ground pen- etrating radar and sonde tracing, to locate buried services. These include water pipes, storm water and sewerage drains, as well as electrical, tel- ecommunications and fibre optic cables. The utili- ties are then surveyed by engineering surveyors and draughted onto AutoCAD 2D and 3D draw- ings.” Bosch Munitech’s services are custom de- signed to suit the specific USL requirements of consulting engineers, environmental specialists, construction and mining companies, municipali- ties, small civils and industrial plants. For example, the smaller contractor who needs to avoid buried services during excavation, only requires scanning of a small area for underground services, to indicate the position of existing ser- vices, without having to identify the type of service. The company’s full USL facility – which is nec- essary for planning new pipe designs, utility diver- sions and new construction – involves the latest non-intrusive techniques to establish, not only the position and depth of buried utilities, but also the type, size and origin of underground services. By gaining access at points, like chambers and sub stations, the type and size of services can be identified. Individual routes of cables can then be traced by inducing target signals onto target lines. Key benefits of utility detection include ac- curate utility drawings for design purposes, less damage caused to essential services dur- ing excavation, reduction of costs caused by services damage, re-designs and interruptions and a safer working environment for field staff. Bosch Munitech’s utility detection and mapping services, which were launched in Gauteng six years ago, are now offered throughout the coun- try, from USL branches in Johannesburg, Durban and Cape Town. The company’s utility management solutions also include water and wastewater, operations and maintenance, solid waste management and geo- graphical information systems. The motion used when drawing wire also plays a role in getting the job done. While some peo- ple rip and tug at the wire with as much force as possible, more experienced electricians will tell you this a quick way to strip and damage the wire, or in some extreme cases even cause the wire to snap. The name of the game is patience. Smooth, measured motions, with careful atten- tion to the progress of the wire will get the job done in the fastest time possible. Enquiries: +27 (0)10 202 3300

credibly frustrating and should be avoided. Many people prefer to pull wire by themselves. While this is fine, bear in mind that sometimes drawing wire is not a one person job. With two people – one on each side – it is possible to get the job done much more quickly. A factor often neglected is the importance of adequate lubrication. While some people are adamant they can muscle through the job, lubri- cation applied in the right place (normally at the connection between the wire and the draw wire or fish tape), ensures that the entire job will go more smoothly.

the idea of wire that can draw itself through con- duit, this is simply not possible. Draw wire and fish tape are the most common items of equip- ment used, but every electrician will have a spe- cial piece of equipment that he or she prefers for drawing wire; whatever you feel is necessary to help get the job done is fine. It is important, no matter what method you are using, to make sure you keep the wire as straight as possible. Any knots (even at the point of con- nection with draw wire or fish tape) can lead to difficult situations, where the wire gets caught on its journey through the conduit. This can be in-

Enquiries: +27 (0)31 535 6000

SPARKS ELECTRICAL NEWS

NOVEMBER 2017