Tag Archives: Zest WEG Group


A generator set installation at a Cape Town private hospital will soon be commissioned by Zest WEG, providing a plug-and-play solution with high reliability and minimal downtime.

“In a design that suited the hospital’s severe space constraints, Zest WEG built the generator, transformer and remote radiator into special ISO shipping containers in a double-stack configuration,” Johannes Nel, operations manager – production at Zest WEG. “The contract also included the refurbishment of the client’s existing 1,000 KVA 400V MTU open-type generator which was included in the solution.”

The new genset expands the hospital’s standby generating capacity to 1 MVA continuous rating, allowing 100% of the institution’s functions to continue as normal during periods of load-shedding. Nel also highlights that reliable supply was key to the hospital’s safe and efficient operation, whether from mains or back-up supply.

To reduce the project lead time as much as possible, the delivery of certain imported components was arranged well in advance. The containerised solution was constructed and extensively tested at the Zest WEG genset manufacturing facility in Epping, saving time during installation.

“It was critical that any downtime be kept to an absolute minimum, as hospitals need to run continuously,” Nel says. “With our expertise, product range and experience in the health sector, our design, installation and commissioning strategy was able to align closely with this priority.”

A dry-type step-up transformer allows the generator to connect to the 11 KV council electricity supply council supply, which will reduce hospital downtime during commissioning. The resin-sealed transformer also provides a long-lasting solution with low maintenance and a high safety factor due to the absence of oil as a coolant.

Nel explains that another vital concern was the hospital’s proximity to a residential area, demanding that the noise level of the generator be kept within strict limits. This requirement was successfully achieved during testing, with the noise level kept within 65 decibels at a distance of seven metres.

In addition to conducting a complete engine rewiring, Zest WEG also upgraded the generator controller, giving the customer improved ability to monitor the generator’s operation during load-shedding. The modern controls help protect the generator and optimise the lifespan of critical equipment.

While certain aspects of the contract’s timing have been affected by Covid-19 lockdown regulations, the final commissioning and handover to the client is projected for the end of May.


Zest WEG has delivered a locally manufactured main power transformer to a wind farm project near Swellendam in the Western Cape.

The 45MVA transformer will receive 33kV from the wind turbines and step this up to 132 kV for the main power grid. Stuart Brown, sales team leader, transformer division at Zest WEG, says the design and construction of the power transformers shows the high level of expertise and technical capacity in South Africa.

“With two of the few local transformer manufacturing operations in the country, we have the added advantage of being able to draw on the technical experience of our parent company, the world-wide WEG group,” says Brown. “In designing power transformers for renewable applications, we gain valuable insights and important skills transfer from WEG experts in the US and Brazil.”

Brown highlights, for instance, that the high harmonics content is a feature of the inconsistent cycles associated with renewable energy sources. This requires a specialised design and manufacturing capacity to ensure that a transformer in this application delivers its intended lifespan and high reliability.

He says the local manufacture of main power transformers can contribute significantly to the local content of renewable power projects, which by their nature must import much of their specialised equipment. This helps project developers to comply with the Department of Trade and Industry’s local content requirements.

“Zest WEG’s B-BBEE Level 1 status allows renewable energy developers and contractors to align their projects with South Africa’s transformation goals,” he adds.

The transformer was built at Zest WEG’s Heidelberg facility which, combined with the WEG global operations, offers the market more than 30 years of experience in the design and production of larger power transformers. Following comprehensive testing at the facility’s laboratory in 2019, the transformer was delivered to site and assembled under the supervision of Zest WEG engineers in January 2020. They also conducted full on-site testing of the unit, as well as cold commissioning.

“The size of the transformer – at 5,7 metres high and 7 metres long – meant that it could not be transported in one piece,” Brown says. The total weight of the assembled unit is 70 tonnes.

Ongoing technological improvements and constant upgrades at the Heidelberg plant ensures its state-of-the-art capability. The testing conducted at the factory includes lightning impulse withstand tests and temperature-rise tests, especially relevant to simulate the potentially high temperatures where transformers are located.


In an innovative ‘first’ to keep a customer’s mining project in the Democratic Republic of Congo (DRC) on schedule despite the impact of Covid-19, Zest WEG successfully conducted a remote witness test of Medium Voltage (MV) Variable Speed Drives (VSDs) in WEG’s Brazil factory.

“These are extraordinary times, and require extraordinary measures,” says David Spohr, business development executive for high-voltage equipment at South African-based Zest WEG. “With the restrictions on international travel, we had to think creatively about how to complete this final step in the manufacturing process – the witnessed Factory Acceptance Test (FAT) – before the equipment could be shipped to the DRC site.”

Under normal circumstances, these tests would require the customer to travel to Brazil and spend a week at the factory witnessing and signing off a range of detailed test and equipment requirements.

This order comprised two 7MW 3300V WEG MVW01 VSDs for the ball and SAG mill drive application and two 1,2MW 3300V WEG MVW01 VSDs for the HPGR mill application. Both applications required non-standard features, namely “frozen charge protection” software on the ball and SAG mill application and a “master & follower” configuration on the HPGR mill application.

“It was essential that we did not delay the customer’s project, so we arranged to conduct the witness test using web-based communication software,” says Spohr. “This allowed the participation of Zest WEG experts, the engineering contractor and the end-user, all from the safety of their homes in Johannesburg – communicating with five testing technicians in the WEG factory in Brazil.”

Using a high-definition camera and web-based communication software, the factory technicians were able to walk the contractor and end-user through each element of the FAT, with clear and real-time visual images of the test results and equipment on the factory floor. The tests continued for three days, beginning at 13h00 and ending at 19h00 to account for time zone differences. Testing covered three key areas – PLC communication software integration, full functional testing and full load testing.

“As with any other witnessed FAT, the customer was provided with a comprehensive results report by WEG,” Spohr says. “This enabled the customer to check, in exactly the same way, that the remote FAT results were within the required tolerances.”

Spohr notes that this pioneering step is likely to influence the way that these tests are done in future. “It has shown that the testing can be done to the same standards, but with significant savings in time and cost,” he says.


A range of WEG geared motors – with benefits including efficiency and reliability – will soon be available to customers in South Africa and the rest of the continent from Zest WEG.

According to Zest WEG national sales executive Johan van Niekerk, the WEG WG20 range is a natural extension of the company’s offering in electric motors, and will be available from the third quarter of 2020. The geared motors will be distributed and supported through Zest WEG’s established footprint of strategically located branches and outlets across the continent.

“In keeping with our local production philosophy – and to reduce lead times to customers – the geared units will be assembled in South Africa,” van Niekerk says. “Zest WEG has made a substantial investment in new assembly facilities, including hydraulic presses and assembly tooling.”

He also notes that the geared motors will allow the company to expand services in new markets including the packaging, recycling, food and beverage sectors.

Cas de Jager, Zest WEG geared motor specialist, highlights that local assembly allows reduced time-to-market.

“Underpinning our quick turnaround time will be our skilled employees and local stockholding of a full range of gears, flanges, housings, shafts, bearings, oil seals and other components,” says de Jager.

The components for the geared motors are manufactured by Watt Drive in Austria, an established gear technology specialist and part of the global WEG group. Watt Drive offers a complete range of combinable drive systems for production machines and industrial manufacturing plants. In addition to providing high quality components, the company is also training Zest WEG personnel at its Austrian facility and will regularly send technical experts to continue building capacity in the South African operation.

There are various benefits inherent to geared motors, says de Jager.

“A key improvement delivered by geared motors is their high level of efficiency,” he says. “Only about 1,5% of mechanical efficiency is lost per gear stage, so a two-stage gear unit would be about 97% efficient.” He highlights that they are also very reliable, robust and durability, making them economical to maintain.

Van Niekerk says Zest WEG’s extensive footprint around South Africa and linkages with the rest of the continent positions the company well to introduce the WEG WG20 range to new and existing markets.

“Our geared motors will be given the high levels of service and after-market support for which we are well-known,” he says.


Usually the last contractor on site, electrical instrumentation and control (EC&I) specialist EnI Electrical puts extra effort into helping clients around Africa meet their scheduled start-ups.

With decades of experience in mining and industrial projects on the continent, the Zest WEG group company understands the challenges that developers face, Russell Drake, general manager operations at EnI Electrical, says. Among its mining projects, it is currently involved in a large copper mine expansion in Zambia.

“Large project implementation is complex, and is often made more challenging by the logistical constraints that many African projects face,” Drake says. “There are invariably delays at various stages, which places more pressure on the EC&I contractor, who must in many ways ‘complete’ the roll-out.”

EnI Electrical works extensively with project houses and directly for mining companies, and is a preferred supplier to many of them. A key reason, he says, is the proactive attitude that underlies its depth of technical expertise.

Calvin Fisher, EnI Electrical overhead lines manager, emphasises the importance of on-time completion, combined with reliable electricity supply.

“With the various issues that may delay stages of a project, there is usually growing urgency as the deadline date approaches,” Fisher says. “This is normally when EnI Electrical enters the project, so we are accustomed to working under some extra pressure. Our dynamic team actively looks for ways to advance the work, especially when the previous phases may not be quite ready for us to begin.”

He notes that the team often does not have all the site access they need, so it requires some innovation to push the job along.

“We may even collaborate with other contractors if we have spare resources, for example, to help them complete their work so that we can start ours,” he says. “Our focus is on being part of the solution, and this is an approach that really helps clients meet their deadlines.”

The linking up of electrical infrastructure, connections and equipment is one of the final stages to allow any project to start operating. In this role, EnI Electrical installs a wide range of electrical infrastructure including medium and low voltage cable reticulation, motor control centres, lighting, earthing protection and energy management systems.

Its control and instrumentation work ranges from process instrumentation and plant automation, to custom control stations and fibre or copper networks. The company also designs and installs overhead power lines up to 161 kV and substations.

“Our permanent bases in countries like Zambia and Ghana – with significant in-country investment in technical assets – underpins the efficiency of our work,” Drake says. “We understand our working environment very well, so we can quote accurately and fairly. This is vital to reduce variations during projects, as this can be disruptive to the project and the client.”

He emphasises that EnI Electrical’s experience and technical capability give it the confidence to present the most cost effective solutions to clients. This provides certainty and reduces overall project risk.

“We also take pride in developing local capacity in the countries where we are based,” he says. Operating from locally registered entities also ensures legal compliance and maintains a social licence to operate.

EnI Electrical’s local operation in Zambia – established in 2002 – employs 188 local staff including highly skilled technical teams. In Ghana, ongoing investment in assets and skills gives that office the capability to run up to R300 million in contracts at any given time, he notes.

“Our success in Africa is built on our specialised expertise and experience, but what clients really appreciate is our willingness and ability to ‘take up the slack’ towards the end of their project when time is not on their side,” Fisher says. “Our close contractor interface and solution-driven approach allow us to do this.”


The recent installation of an impulse voltage generator at Zest WEG’s transformer manufacturing facility in Heidelberg will allow in-house testing of transformers, saving time and money for customers.

According to Ronaldo Bertoldi, engineering manager at the facility, the substantial investment in this specialised equipment positions Zest WEG well for growth within South Africa and the rest of the continent.

“The impulse generator is strategic equipment for us, providing an important service, especially for our larger customers,” Bertoldi says. Where the transformer size is larger than the 72,5 kV Voltage class, impulse testing is a routine test as per IEC 60076-3. Customers have an option to do an impulse test in lower Voltage classes as a type test.

An impulse generator produces short, high-voltage surges to test the strength of electric power equipment against lightning and switching surges. It comprises multiple capacitors that are first charged in parallel through charging resistors by a high-voltage, direct-current source. These are then connected in series and discharged through a test object by a simultaneous spark-over of the spark gaps.

Sales team leader Stuart Brown highlights that the acquisition makes the Zest WEG transformer manufacturing facility one of only a handful of local Original Equipment Manufacturers (OEM) with this testing facility in-house. This enhances local engineering capacity and entrenches global standards.

“Major energy utilities will often require that suppliers have this capability,” Brown says. “It is therefore a valuable resource as we expand the range of our transformers up to 50 MVA, 132 kV units.”

Zest WEG has been manufacturing transformers locally since 2013, with significant growth in its range since 2016. Impulse testing had previously been outsourced and added to the lead time for completing units, he says.

Bertoldi emphasises that impulse testing is important to establish that transformers can withstand waves on the network induced by lightning faults.

“In particular, it tests whether the transformer’s insulation is capable of withstanding such faults,” he says. “In a country like South Africa, where lightning flash density is high, this is a vital exercise.”

Impulse tests are also required by the global IEC 60076 series of standards, he says. These include full wave lightning impulse tests for line terminals and chopped wave lightning impulse tests for line terminals for power and distribution transformers.

“For instance, IEC 60076-3 requires that – for transformers with a rating of more than 72,5 kV Voltage class – the lightning impulse test on the line terminals becomes a routine test,” he says. “This means that it has to be performed at the factory by the manufacturer on every unit leaving the factory.”

The impulse generator will also allow Zest WEG’s transformer facility to test its own new product prototypes. These are continuously developed with the technical support and shared resources of WEG’s research and development facilities in Brazil.


With electric motors consuming almost 70% of industry’s energy, companies are always looking for better motor efficiencies. For many years, motor efficiency has been well defined; however, when driven by a variable speed drive (VSD), the VSD efficiency and the total efficiency of the VSD and the motor has not been well understood. For many years, motor efficiency has been well defined. Choosing the right product combination can also be more difficult as manufacturers’ data is not always easily comparable. This is where the international IEC61800-9 standard comes to the rescue, according to global motor and VSD manufacturer WEG.

The IEC61800-9 standard – based heavily on the previous EN 50598 standard – gives manufacturers a clear framework for grading a complete motor system. End-users can compare the overall efficiency of a manufacturer’s products, irrespective of design and component selection.

The IEC61800-9 standard uses the Extended Product (EP) approach. This considers the efficiency of the Motor System, which is comprised of the Motor, the Basic Drive Module (BDM), the Complete Drive Module (CDM). Together, these make up the Power Drives System (PDS), which also includes any switchgear and controls.

This terminology sounds confusing but is just a technical way to say: Switchgear + VSD + Motor. The efficiency levels are defined by considering eight different operating points, covering low to high speed and torque. The user can easily compare his application load and speed requirements to the motor system defined speed and torque points.

The EP approach employs a semi-analytical model to calculate the efficiency of each of the components at the operating points of the driven equipment. The calculations are also based on tested and verified values. This results in the most efficient component selection for the application.

Using this standard, the user may be assured that:
• A motor complies with the defined motor efficiency levels of IE1, IE2, IE3, IE4 or IE5;
• A VSD complies with VSD efficiency IE0, IE1 or IE2; and
• The manufacturer’s motor and VSD used in combination will meet or exceed a system energy standard of IES0, IES1 or IES2.

Using this EP approach, the European Commission expects the increasing use of more efficient systems to help achieve its targets for carbon dioxide (CO2) reduction. In line with these efforts, WEG VSDs and IE2 motors in combination achieve IES2. And significantly, WEG’s VSDs and IE3 efficient motors exceed the highest system levels of efficiency. Additionally, WEG has product lines that exceed even IE4 and IE5 classifications.

Recognising that global population growth and economic development is driving up energy demand around the world, the European Union has set stringent targets to reduce CO2 emissions. These aim to cut emissions by 40% by the year 2030. This means creating more renewable energy sources, and also increasing the energy efficiency of industrial systems. Studies suggest that almost half of global energy consumption comes from industry – followed by commercial and residential use.

The EC’s regulation 640/2009 already requires that all electric motors operated from a variable speed drive or inverter must adhere to a minimum of IE2 to be eligible for sale. Fixed-speed applications must meet a minimum of IE3 to comply.

Where a motor does not operate at its nominal torque and speed, the variable speed drive represents a significant opportunity for energy optimisation. In addition, the greater the range of speed variation results in a greater PDS efficiency. Using WEG’s IE2 motors with any WEG variable speed drive can achieve an efficiency classification of IES2. However, using other WEG lines of motors with the right drive, much better levels of efficiency can be reached.

WEG has a complete line of variable speed drives which exceed the IE2 requirements outlined in the IEC61800-9 standard. When combined with its robust and reliable motor line, the products create an integrated solution for all applications.


As a leading electrical control panel manufacturer, WEG Automation Africa stays at the cutting edge of innovation through its research and development driven approach which sees continuous product improvement setting benchmarks within the industry sector. The company was previously known as Shaw Controls and is part of the Zest WEG Group which is, in turn, owned by Brazil-based WEG Group.

According to Tyrone Willemse, business development manager – projects and contracts at WEG Automation Africa, the focus throughout the process is on safety and quality as well as local manufacturing capability. The company manufactures a range of low voltage (LV) and medium voltage (MV) electrical switchgear as well as LV fixed and withdrawable motor control centres (MCCs).

“Our fixed pattern boards have three configurations – front entry, back entry and back-to-back,” Willemse explains. “We can supply these in top or bottom busbar, or cable supply entry, to suit the customer’s glanding and entry preferences.”

WEG Automation Africa’s latest family of fixed pattern boards is internally arc classified at the highest level – Class C in accordance with IEC 61641 guideline.

Willemse says this makes it possible to conduct an assessment and repair of the board after a flash and then it can be returned to temporary use after a dielectric test, to minimise unscheduled downtime. He notes that the IEC61641 guideline is starting to be introduced into LV designs to enhance safety.

“The fully withdrawable MCC option offers the major advantage that operators do not work on a live board in front of the bucket,” he says. “This allows the technician to take the bucket out and move it to a safe environment before working on it.”

Significantly, WEG Automation Africa has introduced a new, fully-withdrawable MCC compliant with both IEC61439 and IEC61641 guidelines. While initially sourced from WEG’s manufacturing facilities in Brazil, the model is being considered for local build.

With the use of Solidworks modelling computer-aided design and engineering software, the MCC chassis is pre-punched to reduce wiring time. All digital components are loaded onto the system and carefully placed in the design of MCCs, so that equipment can be assembled and replicated to the highest standards.

“Our closed-loop project planning and control system also contributes to ensuring optimal efficiencies in the manufacturing line, saving both time and money for our customers,” he says.

The availability of Aluzinc instead of mild steel for the panel shells is an added advantage to the standard range of panels. This assists with the continuity of the earthing system and is corrosion-resistant, adding to its safety.

WEG Automation Africa’s extensive facilities at Robertsham in Gauteng also manufactures a variety of supplementary equipment for use on process and other plants. These range from custom-designed PLC panels, standalone starter panels, junction boxes, remote isolator panels and control desks. Panels are designed and produced for indoor and outdoor applications, whether skid-mounted, in a sub-station, in a container, or in a prefabricated room or specially constructed E-house.


Innovative and fit-for-purpose design was the winning formula that secured WEG Automation Africa, formerly Shaw Controls, the contract for a containerised substation and control room solution for a remote tin mine in the Democratic Republic of Congo.

According to Tyrone Willemse, business development consultant – projects and contracts at WEG Automation Africa, the isolated location of the mine and the challenging logistics made the modular solution ideal for the mine. The substations are each housed in a six-metre-high cube container. A total of 14 units were supplied, comprising MV rooms and LV rooms.

Willemse says. “The unit’s dimensions and robustness had to allow for a long journey, including along a very difficult 200 km road to reach the mine site.”

“Every part of the process plant has its own designated MCC that provides electrical power and control for areas including the primary crushing circuit, the plant feed, regrind mill, tailings thickener, and the product dewatering and handling circuits.”

In addition to meeting safety compliance regulations, the design includes three-way locking systems, LED lighting, fire detection systems and a safety interlock to the fire system for air conditioners. Backup power supply is provided to all the exit lighting. To ensure easy cable entry, glanding plates were carefully located not to overlap with the container’s support beams.

“Working in close collaboration with the engineering house, careful planning could be done upfront to ensure that nothing was overlooked,” Willemse says.

“In the design, full consideration was given to the placement of elements like platforms, walkways, doors, viewing windows and air conditioning units,” he says. “We also took responsibility for the logistics of getting everything to site.”

Willemse highlights that this turnkey solution demonstrated WEG Automation Africa’s containerised substation design and engineering capability, as well as its full local manufacturing capacity lifting it above other MCC manufacturers or assemblers. The containerised solution comes with a full data pack, quality control documentation and an operation and maintenance manual in accordance with ISO9001.

“With our expertise, capacity and experience of working in Africa, we were able to reduce the risk and turnaround time by tackling the entire contract in-house,” Willemse says. “The extensive testing and cold commissioning enabled by our modus operandi and facilities also gave the mine peace of mind that the unit would function as required when it arrived on site.”


Africa has embraced the innovation that drives WEG products and services, with customers seeing value in constant technological improvement.

Siegfried Kreutzfeld, CEO of the South African based Zest WEG Group, explains that WEG is quick to introduce its new products into the African market, sometimes even before launching elsewhere in the world.

“We pride ourselves on the significant investment we, as WEG, make in research and development,” Kreutzfeld says. “About 2,6% of our net revenue is ploughed back into continuous product improvement as well as new development. This keeps us at the cutting edge of technology.”

The result of this intense commitment to innovation is that 43,7% of all WEG products sold in 2018 were launched in the last five years. Another indicator is that Brazil-based WEG Group holds 174 patents that are used on its products.

Significantly, this has placed WEG among the thousand most innovative companies in the world, ranked by The Global Innovation 1000 of 2014. This world ranking evaluates the total R&D investments of each company, including the strategy, purpose and success of these investments.

“More than 35 years ago, we led the way in South Africa by introducing reliable high performance motors into the mining sector,” he says. “Today, we have a solid market share on the continent based on the trust we have built with our customers. This relationship makes it easier to introduce and test new WEG technologies in Africa.”

While continuously improving its products, WEG also closely monitors how they perform in the field, Kreutzfeld notes. “An indicator of the confidence we have in WEG technology is that we provide a five year warranty on WEG motors,” he says. “This is unique on the continent and difficult for competitors to match.”

WEG’s innovation and the market trust are paying dividends. Despite the country’s poor overall economic performance, Kreutzfeld says Zest WEG Group is targeting 15% growth with its high quality offerings.

Among the latest WEG technologies are energy-efficient IE3 motors which reduce electricity consumption, and the WEG CFW 11 Variable Speed Drive (VSD) which selects the best efficiency, again conserving energy and saving costs.

Kreutzfeld says that during 2019 a new series of WEG VSDs, specifically for mine fan applications, will be introduced to the market.

WEG’s innovative Motor Scan device is another important development, harnessing connectivity and the power of Industry 4.0 technology to monitor motor health. Attached to the motor itself, the WEG Motor Scan gathers vital data including vibration, temperature and running time. This is communicated wirelessly to a hand-held device or to WEG’s Internet of Things (IoT) platform.

“Extending electric motor life is going to be an important trend in the market, especially in the mining sector,” Kreutzfeld explains. “Only a decade ago mines expected less than two years of life from an electric motor, and we have been able to change that. Using Motor Scan will allow end users to optimise routine maintenance and extend motor life.”

Another technological innovation is the large WEG slipring motors considered ideal for the cement industry. Cement plants place high wear demands on electric motors, and WEG has developed features to address this challenge.

“We innovate by being close to our customers and seeing the problems they face,” he says. “You cannot pursue innovation without understanding customer applications and market trends.”

To drive this process, WEG established a Scientific and Technological Committee in 1998. This forum allows WEG’s engineering team to engage with five university specialists, three from abroad and two from Brazil. The forum meets every two years to discuss market trends, technology and innovation, and importantly how to apply this to WEG products.

“During this meeting, we share new concepts and products with the academic experts,” he says. “This collaboration has many mutual benefits. We gain ideas and feedback, and the universities can gather topics for their students to research.”

Inside WEG itself, there is a team focused on new product concepts and technologies. Kreutzfeld says many of these might remain in development for years, even decades, and are only commercialised in response to market trends.

“This pipeline of innovation is vital to meet changing customer needs and is what sets WEG apart,” Kreutzfeld concludes.