Modern Mining February 2022

MOTORS AND DRIVES

A WEG motor being installed on a fan. he says. “Our Johannesburg facility, for example, services the gold fields region with motors, drives and other equipment, and our trucks are on the road every day to deliver.” These support services include specialised tech- nical input from Zest WEG people, who can give detailed guidance to plant managers who want to improve or upgrade aspects of their operations. When installing VSDs, for instance, there are many variables to consider and implications that may not be obvious. “Project details like the length of cable to the motor, or the positioning of the VSD in the existing motor control centre, all affect the final design and installation,” he says. “We have plenty of experience in providing engineering guidelines – either to the end-users or the systems integrators that mines often employ to conduct this work.” To further ensure that motors and drives are opti- mally selected, installed and maintained, Zest WEG conducts ongoing training for customers and its own staff at its dedicated training facility in Johannesburg. Over 10 600 customers have made use of these skill- building services to date, which includes practical exercises on the equipment itself. “The explosion of digital communication plat- forms during the Covid-19 pandemic now also means that we are offering more of our training online,” says Du Plessis. “This has proved very popular among engineers and operators who can’t afford the time away from the plant. Access to our online learning allows us to upskill customers and also open valuable opportunities for improving plant performance.” 

a process plant – not least the motors and drives – need regular servicing and maintenance, mak- ing it crucial that customers have quick and easy access to the right skills and spares. With over 40 years in South Africa, Zest WEG has established a strategic network of branches and warehouses in locations including Rustenburg, Middelburg, Trichardt, Richards Bay, Pietermaritzburg, Durban and Cape Town. “Many customers don’t keep their own spares, but instead rely on us to maintain that stockholding,”

A WEG motor in a screening application.

Key Takeaways  More than 60% of the overall electricity consumed in mineral processing plants is used on motor driven systems  Variable speed drives can lead to energy savings of up to 50% in certain applications such as pumps and fans  With a focus on optimising plant uptime, Zest WEG ensures a high avail- ability of its low voltage motors in the 525 V range  WEG’s W22 motor range comes in different energy efficiencies, from the IE1 standard efficiency rating to IE3 premium efficiency units and lately the IE4 super premium efficiency motor  WEG has ensured that 95% of its IE4 units have frame sizes compatible with the IE3 equivalents  Zest WEG conducts ongoing training for customers and its own staff at its dedicated training facility in Johannesburg

28  MODERN MINING  February 2022