In the face of rapidly rising electricity costs in South Africa, Zest WEG is phasing in IE4 super‑premium efficiency motors in its WEG W22 range from April 2021 – which will save on customers’ bottom lines and help reduce the load on the national grid.

According to Fanie Steyn, electric motors manager at Zest WEG, 2021 will see local energy prices rising above R1/kWh for the first time. This makes it the ideal time for the introduction of WEG IE4-rated motors, which will be available in the size range between 37 kW and 375 kW.

“Unlike many countries around the world, South Africa has not regulated the use of energy efficient motors at the level of IE2 or IE3,” says Steyn. “Nonetheless, we have taken the proactive step of making the IE4 level of efficiency available to customers at no premium on the IE3 units.”

Some years ago, Zest WEG introduced its WEG IE3 motors to the country at little or no additional cost relative to its IE2 motors, with the same goal in mind: making both customers and the country more energy efficient.

Specified under the International Electrotechnical Commission (IEC) 60034-30-1:2014 standard, IE1 refers to standard efficiency and IE2 to high efficiency; the IE3 and IE4 ratings are for premium efficiency and super-premium efficiency motors respectively.

“The efficiency of 96.3% on an IE4-rated 110kW motor, when compared to 94.1% on an IE1-rated motor, can save users hundreds of thousands of rand in energy costs over a 10 year period,” he says. “Not only will these IE4 motors be more cost effective to run, but they have been designed with a number of new features that bring considerable benefits.”

Steyn emphasises that WEG IE4 super-premium efficiency motors meet IEC efficiency levels when running on 50 to 100% of load; efficiency is kept constant, which saves energy and ensures minimal losses through various loading points. The innovative frame design also allows maximum heat dissipation.

“Motor frame design plays a crucial role in thermal performance, as it is responsible for the outward transfer of heat generated inside the motor,” says Steyn. “Running cooler means that our motors have increased life spans, allowing Zest WEG to offer a five year guarantee on our WEG W22 electric motor range.”

The motors’ increased mechanical rigidity – achieved by integrating the front and rear feet sides – affords easier installation, higher mechanical stiffness and improved distribution of the mechanical thrust imposed by the load.

“As a first of its kind, our flexible terminal box mounting means reduced inventory and quicker modification,” he says. “The terminal box can be rotated in 90° increments to facilitate supply cable connection orientated to the front, rear, top or either side of the motor.”

In addition to the benefits brought by WEG super premium efficiency motors a substantial increase in energy savings can be reliably achieved using WEG Variable Speed Drives (VSDs), which comply with the European Extended Product standard EN50598. This ensures the system efficiency of the motor and VSD combination. As an additional feature, WEG VSDs have energy savings settings which can be user activated, achieving an automatic saving under any reduced load conditions.

“We are excited to build on the phenomenal reputation of the existing WEG W22 electric motor range by offering an even more efficient motor that is truly “next level” state of the art in electric motors, having the same rock solid quality and reliability,” Steyn concludes.