EARTHING, LIGHTNING & SURGE PROTECTION
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Advanced material science in earthing, lightning, and surge protection By Minx Avrabos M odern electrical installations, particularly in low-voltage (LV) and medium-voltage (MV) environments, electrodes can have high resistivity, reducing the effectiveness of fault current dissipation. New formulations now incorporate conductive admixtures such as carbon black and special metallic
Adopting advances in material science allows contractors to deliver safer, longer-lasting, and more cost-effective earthing and lightning protection solutions.
fibres, achieving resistivities as low as 0.01 Ω m (compared with the typical 100–150 Ω m of standard concrete). These advanced concretes not only lower earth resistance but also greatly improve moisture retention, providing consistent performance even in arid soils. This means smaller electrode arrays and reduced excavation costs. 2. Graphene-based earthing electrodes Graphene, a single layer of carbon atoms
require robust earthing, lightning, and surge protection systems. Recent advances in materials science have revolutionised traditional approaches, offering enhanced conductivity, corrosion resistance, and long-term reliability. This article highlights three cutting-edge innovations: highly conductive concrete, graphene-based earthing electrodes, and exothermic welding methods.
exceeding 40 years, even in aggressive soil conditions (chlorides, sulphates, or acidic environments). These electrodes are lightweight and easy to handle, facilitating rapid installation.
arranged in a hexagonal lattice, exhibits electrical conductivity up to 1,000 times that of copper. Electrodes incorporating graphene or graphene composites offer ultra-low resistance—often below 0.1 Ω for standard 3-metre rods—and exceptional mechanical strength. Most notably, graphene’s inert nature provides outstanding resistance to underground corrosion, promising service lives
3. Exothermic welding Reliable earthing depends on low-
resistance, durable connections. Exothermic welding uses a controlled chemical reaction to permanently bond conductors at the molecular level. These joints match or exceed the conductors’ conductivity, are immune to loosening caused by vibration, and resist corrosion far better than mechanical clamps or compression fittings. For LV and MV projects, exothermic welds ensure minimal maintenance and superior long-term performance. Conclusion Adopting advances in material science allows contractors to deliver safer, longer- lasting, and more cost-effective earthing and lightning protection solutions. Embracing these innovations will be key to meeting the ever-increasing demands of modern electrical infrastructure.
1. Highly conductive concrete Traditional concrete encasement of earth
www.crown.co.za/sparks-electrical-news- magazine
Protection for critical infrastructure and digital facilities By Minx Avrabos I n today’s hyper-connected world, critical 2 surge protection devices (SPDs) at service entrances and distribution boards. This shields against external surges caused by grid switching or lightning.
entering the cabin. Choose devices rated for telecom frequencies and maximum fault currents. Routine inspection: Inspect earth connections and SPD function after storms or maintenance events. Conclusion With digital infrastructure underpinning modern economies, proactive earthing and surge protection are non-negotiable. Integrating layered protection across power, data, and structural systems ensures resilience, maximises uptime, and protects critical operations. www.crown.co.za/sparks-electrical-news- magazine
locations, making them prime targets for lightning strikes. Coordinating tower and equipment cabin grounding is crucial: Design a ring earth: Surround the tower base with a buried ring conductor, connecting it to tower legs and equipment cabin earth bars. This ring collects and dissipates lightning energy. Bond all interfaces: Connect the ring earth to all metallic structures—feeder cables, antenna masts, and cabin frames—with short, direct conductors. Isolate signal grounds: Ensure signal and power earths are bonded at a single point to avoid ground loops, which can induce surges into sensitive electronics. Surge protection on all lines: Install SPDs on AC power, DC supply, and coaxial lines
infrastructure, including data centres and telecom base stations, underpins economic activity and communications. Maintaining uptime is paramount, yet these sites remain vulnerable to electrical hazards, including lightning strikes and transient surges. Robust earthing and surge protection are fundamental to safeguarding these assets. Data centre vulnerabilities and surge mitigation Data centres house sensitive automated logic networks and vast arrays of IT equipment. Even momentary surges—often too fast or subtle for legacy grid protection— can propagate through power and data lines, causing logic errors, hardware damage, and downtime. To mitigate these risks: Equip all entry points: Install Type 1 and Type
Local protection: Use Type 3 SPDs near critical servers, network switches, and storage devices. These devices capture residual surges that bypass upstream protection. Equipotential bonding: Create a low- impedance path to earth by bonding all metallic parts—power racks, cable trays, and enclosures—to a central earthing bar. This prevents dangerous voltage differences that could disrupt sensitive electronics. Regular testing: Continuously monitor earth resistance and SPD status. Degraded Earth systems and spent SPDs reduce the effectiveness of protection. Telecom base stations: coordinated grounding for high-exposure sites Telecom towers are often sited in exposed
In today’s hyper-connected world, critical infrastructure, including data centres and telecom base stations, underpins economic activity and communications.
SPARKS ELECTRICAL NEWS
SEPTEMBER 2026
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