Tag Archives: a Zest WEG Group company


WEG Variable Speed Drives (VSD) offer the agricultural sector the ability to reduce the operating cost on automated water collection systems with a reduction in motor energy consumption when the motor speed is reduced.

In addition, the WEG Variable Speed Drive allows the monitoring of all functionalities of a pumping operation including special functions that will not only save operating costs but will optimise, control and protect the entire irrigation system.

Just as significant is the VSD ability to automatically send commands to the electric motor thereby facilitating optimum control of the pumping installation. This allows greater effectiveness when irrigating.

The WEG CFW 700 frequency inverter or VSD provides accurate speed variation for the electric motor ensuring it operates according to the irrigation system pressure needs (PID), and with the necessary field telemetry it can also take different land inclinations into account.

Another important benefit is the WEG VSD’s ability to detect low pressure indicating leakage in a pipeline. With this early warning from the WEG VSD, end-users can eliminate the need for specialised equipment and be able to take remedial action as soon as possible.

Where water is being pumped from a river to the dam for further irrigation, use of the WEG VSD will allow optimum control of the water level. It will prevent overflow situations, and dry pumping can be set up without the addition of flow sensors.

The WEG VSD can be used to facilitate sleep and wake modes in the pump operation. This facilitates significant cost savings as pumping can then be done on a demand driven basis only.

Where there are multiple pumps in use at the same pump station, it is possible using WEG Pump Genius Software and the WEG CFW11 VSD to automatically alternate motor usage to ensure that each motor/pump combination has equal operation time. This will avoid one pump being subjected to excessive wear and regulate the wear across all the pumps resulting in the lowest total cost of ownership for the installation.

Optimisation of water in the agribusiness undoubtedly improves product quality and production between harvests and allows optimum use of land, and WEG VSDs will assist in achieving this.


Electric motor applications require a reliable, robust fit-for-purpose product that will give the end user the requisite low total cost of ownership. Fanie Steyn, manager responsible for rotating machines at Zest WEG Group, says it is encouraging that most industries in southern Africa have woken up to the fact that purchasing the standard efficiency motor is not the best long-term option.

As the leading supplier of electric motors in southern Africa, Zest WEG Group offers the most comprehensive range of low voltage electric motors available on the continent.

In previous years, all WEG low voltage electric motors were manufactured at WEG Brazil, but today this major group’s manufacturing network extends to four continents. All facilities adhere to stringent quality control processes, are ISO 9001:2015 accredited and motors meet all the requisite international standards and regulations.

“The depth of the WEG low voltage range of electric motors allows us to offer customers the best fit for individual applications, and we are also able to draw from a product line-up of motors that are engineered for specific application requirements,” Steyn says.

The WEG low voltage electric motor range starts from 0,18 kW motors that would be used to drive small fans or used in exhaust applications and goes up to 1,250 kW motors which would drive massive ventilation fans or pumps.

Significantly, Zest WEG Group has such confidence in WEG motors that all the WEG W22 low voltage units now carry a five-year guarantee as standard.

Electric motors for specialised applications would include slip ring motors, roller table motors, saw arbor motors, gas pump motors, pad mounted motors, smoke extraction motors, permanent magnet motors, cooling tower motors and wash down motors for hygienic applications.

“Another significant trend reaping benefits for customers is the move towards using premium efficiency electric motors, also known as IE3,” Steyn says. “While WEG electric motors are still available in standard efficiency, also known as IE1, there is a remarkable increase in customers requesting IE3 motors because of the obvious energy savings that can be achieved.”

Zest WEG Group operates an extensive branch and distributor network ensuring easy access for customers across the sub-Saharan region. Steyn says customer demand across the region is carefully monitored and stockholding at its head office and branches is maintained in accordance with this to ensure the highest possible level of access to our premium product. The group’s nine strategically located branches in sub-Saharan Africa are supported by a team of skilled competent technicians in the field.

Underpinning this support to industry, is the motor related product training offered by Zest WEG Group to its customer base.


Reducing energy consumption is a reality for all industries in South Africa, and the WEG W22 IE3 premium efficiency electric motor can rightfully claim to be the most efficient motor that is turning industry in the country.

Available from Zest WEG Group, the WEG W22 IE3 is available in models with a rated capacity up to 1,000 kW and has been engineered specifically to reduce energy consumption optimising on total cost of ownership in numerous applications.

The WEG W22 IE3 product line was engineered using the latest generation computational tools such as structural (finite element method) and fluid flow analysis as well as electric design optimisation software.
This resulted in a robust product that offers reduced energy consumption and thermal efficiency as well as a reduction in noise and vibration levels.

Fanie Steyn, manager responsible for rotating machines at Zest WEG Group, says that because a chain is only as strong as its weakest link, during design close attention was paid not only to the internal efficiencies of the working motor, but also to the elements constituting the external components of the designed motor.

Focus on the frame/housing
The frame is a fundamental component in the design because, besides constituting the mechanical structure reference, it is the main conduit responsible for the heat dissipation generated inside the electric motor.

“In addition, the frame and the end shields ensure the enclosure of the electric components, protecting them against the environment where the motor is installed,” Steyn says. “The frame design ensures high thermal exchange and high reliability where mechanical strength is essential.” The terminal box is located at the front of the frame thereby increasing the heat dissipation area and providing a uniform air flow over the motor frame.

Reliability of the frame was also deemed important, so careful consideration of construction materials led to the selection of FC-200 cast iron which is produced in WEG’s own facilities. Interestingly, this is the same material that is used in WEG’s explosion-proof motors.

Fan and fan cover
The main function of the fan, when assembled directly on the motor shaft, is to promote the air flow over the frame fins, thus dissipating the heat generated inside the motor.

The function of the fan cover is to protect the fan against external agents and to ensure continuous air flow over the motor fins regardless of the environmental conditions within which the motor is operating.
As a natural consequence, when the cooling system is operating to promote heat dissipation, it generates acoustic noise and mechanical losses which can be caused by a combination of the friction of the fan blades through the air and ineffectual design of the fan cover’s shape.

Good ventilation is key to reducing the mechanical losses, particularly for two-pole motors.
Due to its high efficiency, an IE3 motor has inherently less demand for heating removal, so the ventilating system can be optimised to reduce mechanical losses and consequently acoustic noise.

WEG’s design on the cooling system on these new motors was conceived using the most advanced simulation software and fluid flow analysis software, resulting in an innovative aerodynamic profile with reductions in both mechanical and acoustic noise.

Terminal box
Because the terminal box is the point of contact between the user and the motor, WEG first carried out a field survey amongst installation and maintenance experts to determine optimal design performance.
This research resulted in a new terminal box concept that prioritises the interface with the user, providing easier access and handling of the power and accessory cables and ensuring more reliability and versatility in the motor installation.

The new terminal box allows improved cable housing, ensuring larger contact areas between the cables and the motor terminals and allowing correct tightening torque.
The diagonal cut design of the terminal box base and the terminal box cover enables easier access to the electrical connection and gives a better view of the interior of the terminal box during installation procedures.

Using the same WEG exclusive BMC (polyester with 20% fibreglass) die-cast terminal blocks that are used for the terminal blocks of hazardous area motors ensures high electrical insulation resistance and durability. In addition, the accessory cable connections are made with quick coupling connectors.

“With a focus on designing for efficiency, coupled with the ability to understand and implement market needs, WEG W22 IE3 motors are a long-term solution to the ongoing need for energy usage reductions,” Steyn concludes.


On display at Zest WEG Group’s large outdoor stand at Electra Mining Africa this year will be not only its growing range of products but its integrated approach that offers customers significant added value in the execution of large projects.

One of the new products being launched at the event which is expected to draw the attention of visitors and customers is the WEG Motor Scan solution. This innovative device facilitates the monitoring of electric motor performance from a mobile phone and will help mines to avoid unplanned downtime.

According to Alastair Gerrard, integrated solutions executive at Zest WEG Group, the group’s entrepreneurial approach to aligning with customer requirements has led to the cost effective packaging of its offerings.

“In today’s mining sector, it is no longer enough to come to the market with a good product,” says Gerrard. “It is increasingly important to partner with customers in the design and delivery of integrated solutions that will enhance their bottom lines and achieve lower cost of ownership.”

The growth of Zest WEG Group’s product portfolio – as well as the increased size of many aspects of its equipment range – will see the company consolidate its exhibition on one large outdoor stand near the show’s main entrance.

“Moving with the trend of tailor-made solutions that leverage off our extensive portfolio, our integrated solutions approach will provide significant benefits to customers. It also strengthens our ability to supply and manage large projects,” he says.

He emphasises the value of early engagement with customers, which facilitates an in-depth understanding of the specific demands of projects. This enables Zest WEG Group to identify where it can contribute added-value offerings, drawing on its diverse product range that includes electric motors, vibrator motors, variable speed drives, switchgear, motor control centres, mini-substations, generator sets, transformers, containerised or and mobile substations and E-houses.

Also, of interest will be WEG’s recent acquisition of steam turbine manufacturing specialist TGM, which has a well-established reference base in the Brazilian market. Together with this, Zest WEG Group is growing its energy generation offering to include solutions in the renewable energy space.

Gerrard highlights the company’s Level 2 B-BBEE status and its extensive local manufacturing capabilities with four standalone facilities, enhancing its procurement value to customers in the mining sector.

WEG Motor Scan is a performance monitoring solution for electric motor installations. This innovative solution is designed to optimise access to information about the motor’s performance and allows data to be extracted and sent to the cloud. The access to real-time information allows preventive actions to be taken, avoiding unscheduled downtime.

Information is collected by the App using either a smart phone or tablet device, in either Android or iOS versions, and is sent to the cloud via Bluetooth or gateway. The stored data can be analysed on the device screen in a dynamic way or in greater depth on the WEG IoT Platform.

WEG Motor Scan will allow the connection of all the sensors in the plant, enable naming and monitoring of as many electric motors as required, analyse data sent to the cloud and synchronise the data through the WEG IoT Platform. But, most importantly, this solution will allow end-users to find their motor from anywhere in the world.


Zest WEG Group combines its local manufacturing capability with WEG’s range of world class products to engineer energy solutions for customers around Africa, according to the group’s integrated solutions executive, Alastair Gerrard.

Gerrard also emphasises Zest WEG Group’s extensive network of agents and distributors across the continent, who provide vital insights into local conditions, needs and constraints.

“Our solutions are not off-the-shelf, and are tailor made for individual application requirements,” he says. “Our team spends time gaining an in-depth understanding of what the customer really needs, and what the operational constraints are.
In this process, we collaborate with reliable, in-country partners who have local knowledge and experience. This local presence also facilitates quick response times and 24/7 after-sales support.”

Gerrard also emphasises the use of parent company, WEG’s range of motors, variable speed drives and soft starters, as well as its low voltage and medium voltage switchgear.
These products are an integral part of the fit-for-purpose solutions, as is Zest WEG Group’s South African manufacturing capability in terms of generator sets, transformers, substations and other mobile energy solutions.

“Operating a local gen set manufacturing facility staffed by experienced engineers allows us the flexibility to package this offering with an engine and alternator combination to suit the customer preference,” he says.
Zest WEG Group also offers a standard off-the-shelf range of gen sets.

Forming part of Zest WEG Group’s manufacturing operations in South Africa is WEG Transformers Africa which has two facilities capable of producing transformers up to 45 MVA/132 kV and a range of mini substations up to 33 kV.
Also, part of the group is Shaw Controls which is a leading local manufacturer of custom electrical panels, motor control centres (MCCs), containerised electrical solutions and E-houses. He says that E-houses have become popular in Africa as these are pre-assembled and tested in a factory prior to being transported to site by truck.

The focus is on providing integrated solutions in four main areas, says Gerrard, being power generation, electrical infrastructure, mobile energy solutions and group product packages.
Power generation options include diesel, gas, steam, hydro and renewable energy generation solutions, while the electrical infrastructure offering ranges from supply and refurbishment of outdoor and indoor substations to the provision of overhead lines.

Mobile energy solutions, which are engineered to meet specific customer and site needs, are popular in the mining industry but are relevant to any application where operations need flexibility when deploying their electrical systems such as gen sets, substations, skid type solutions or circuit breakers.