Sparks Electrical News September 2026

CONTRACTORS’ CORNER | EDITOR’S COLUMN

Electrifying updates: September highlights & Electra Mining Africa preview W elcome to the September edition of Sparks Electrical News! This month, we shine a spotlight on crucial industry topics: Earthing, Lightning

Looking ahead, our

please stop by and say hello—we value your feedback and ideas. Looking ahead, our October issue will focus on DBs, switches and sockets, Energy Measurement and Supply, and Lighting. If you have news or contributions to share, please note that the article deadline is 9 September. Thank you for your continued support. Enjoy the issue, and I hope to see you at Electra Mining Africa!

October issue will focus on DBs, switches and sockets, Energy Measurement and Supply, and Lighting.

and Surge Protection, Tools & Tooling, and Lighting. Our team has assembled a collection of insightful articles and product updates to keep you informed and inspired. A highlight this September is Electra Mining Africa, taking place at Nasrec from 7 to 11 September. I am excited to attend and look forward to meeting many of our readers and clients in person at the Crown Publications stand LNO1. If you’re there,

sparks@crown.co.za Minx Avrabos | Editor

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PRATLEY’S ALUMINIUM ALLOY JUNCTION BOXES: SETTING A NEW BENCHMARK IN ELECTRICAL INSTALLATIONS

in harsh environments. However, these boxes are intended for surface installations only and are not certified for hazardous areas or to be buried in the ground. Additional accessories and special variants To further enhance waterproofing, Pratley provides standard lid gaskets and optional entry shrouds as accessories. For

specialised applications, such as tunnel installations, the Tunnel Box variant is available, featuring fire-resistant, low- smoke red silicone shrouds and sleeves for maximum safety. Comprehensive support Each Pratley junction box is supplied with installation instructions, and comprehensive product documentation is

available online. This ensures customers have the resources they need for correct installation and regulatory compliance. With their combination of durability, flexibility, and safety, Pratley’s Aluminium Alloy junction boxes are redefining standards in electrical enclosure solutions.

Safety and compliance first Safety is a core consideration in Pratley’s design philosophy. Each box features both an internal earthing boss and an external earthing lug to ensure proper earth continuity throughout the installation. The SABS IP66/IP68 (2 m continuous) rating certifies the boxes’ resistance to dust, water jets, and even continuous immersion up to two meters, providing peace of mind

www.pratleyelectrical.com

Why variable speed drives make sense in modern irrigation

V ariable speed drives are revolutionising irrigation by shifting control from valves to pump speed. Rather than running motors at full power and throttling flow, they adjust motor speed to match crop water needs, reducing energy consumption, electrical stress, and water hammer. Discussions about variable speed drives (VSDs) in irrigation often start with the pump, but they should begin with the crop. Irrigation systems are designed to meet seasonal water demands that vary by season, zone, and daily schedule. Only after assessing the entire process—crop requirements, method, pressure fluctuations, and flow—does pump control become relevant. This is where VSD technology truly demonstrates its benefits. The traditional approach Traditionally, irrigation systems used fixed-speed motors and controlled flow with valves. Lower pressure or flow meant throttling a valve; for start-up protection, pumps started with valves closed. These systems draw extremely high inrush currents at start-up—often 300% to 800% of rated current. Rapid acceleration abruptly transfers torque into the water column, causing surges, stress, and water hammer. Skilled operators are often required, or expensive pressure-operated valves are installed—both of which increase maintenance. What changes with a VSD? With a VSD, motor speed is controlled directly rather than by valves. VSDs deliver full torque from zero speed, enabling smooth, slow starts and gentle opening of non-return valves, virtually eliminating water hammer. Motors draw only the current required, avoiding start-up peaks, whilst the pump simply runs at the speed

transforms fixed-speed pumping into a responsive, automated, energy- optimised system. www.pfs20.com

components such as start-up and pressure- control valves are often unnecessary. Pumps can be started on timers or remotely, without operator intervention. Instrumentation— pressure switches, transmitters, emergency stops—connect directly to drive inputs, eliminating additional hardware and simplifying installation and maintenance. Built-in process control Modern VSDs have on-board PID controllers, so pressure or flow signals feed directly into the drive, automatically maintaining constant pressure or flow. As zones open or close, the drive instantly adjusts motor speed. The pump always runs at the speed irrigation requires, not against valves.

Final thoughts A VSD is a process control device. When applied with a full understanding of irrigation requirements, it

Energy considerations A standard IE1 motor runs at about 0.8 power factor at full load. VSDs convert AC to DC and recreate a controlled sine wave, thereby changing the input characteristics from fixed- speed operation.

VSD PANEL Proudly manifactured in collaboration with CED

This can improve electrical efficiency and reduce reactive impact. The greater energy savings come from the pump affinity laws: • Flow is proportional to speed; • Pressure is proportional to speed squared; and • Power is proportional to speed cubed. Even a small speed reduction significantly reduces power consumption. Rather than throttling excess energy, VSDs reduce energy use at the source—especially important for irrigation systems operating at partial load for extended periods, yielding real financial savings. K What about payback? Most agricultural VSD installations pay back within 9–14 months. This results from: • Reduced maximum demand spikes; • Energy savings through speed control; • Elimination of control valves; • Reduced maintenance; and • Extended pump and pipe life. Savings continue beyond payback. Y CM MY CY CMY

· Himel Automation products have over 30 years of proven perform ance in the industry.

· Distributed across more than 50 countries, ensuring global trust and availability. · More than 100,000 active systems installed, showcasing reliability in real-world applications. · Himel is backed by rigorous international ce rtifications, ensuring quality and safety.

• 5,5kw – 160kw HIMEL VSD PANEL • Ready to Run • Sheet Metal Enclosure • Main Isolator & Fuse Protection • Lightning & Dry Run Protection • Emergency Stop & Safety Switch • Cooling Fans • 3 X Pressure Setpoints

• Pipe Filling • Current Limit • Transducer Bypass

• Auto Restart After Power Failure • Pressure & Current Indication • Includes -16 BAR pressure Transducer • IP22 400V • Remote control

required by the irrigation process. This has three immediate effects: • Reduced electrical stress; • Reduced mechanical stress; and • Lower maximum demand exposure (depending on tariff structure); • Eliminating valves and operators With speed as the control, traditional

SPARKS ELECTRICAL NEWS

SEPTEMBER 2026

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