Supply & Installation of High Voltage Conductor | HHK Earthing and Lighting Protection Systems

HVC Lightning Protection: The Smart Choice for Thatch Roofs and Aesthetics-First Properties

Supply & Installation of High Voltage Conductors

The down conductor connects your air termination system on the roof to the earth termination system in the ground. When lightning strikes, it carries the full current from the strike point down to earth in microseconds. We are talking tens of thousands of amps. If a down conductor fails partway down, that current finds another path: through the building structure, through electrical wiring, through anything and anyone in its way.

HHK supplies and installs high voltage conductors built specifically for this duty. Every conductor we specify is selected, sized, routed, and tested to the requirements of SANS 62305-3 and SANS 62561. When lightning strikes, the current has a safe, predictable, low-impedance path to ground.

What Makes a High Voltage Conductor Different?

A lightning down conductor is not ordinary electrical cable. The current it has to carry rises from zero to 200,000 amps in roughly 10 microseconds. That rate of change produces extreme electromagnetic forces, severe thermal stress, and steep voltage gradients along the conductor's length. Standard building wire would vaporise under those conditions. The conductor has to survive something closer to a controlled explosion than a steady electrical load.

HHK supplies and installs several conductor types, each matched to the application:

Copper Conductors

Solid or stranded copper to SANS 1063 / IEC 62561-2
Minimum cross-section: 50 mm² for lightning protection, 70 mm² for earthing
Available bare, tin-plated, or PVC-sheathed for corrosive environments
Approximately 58 MS/m conductivity with strong corrosion resistance

Aluminium Conductors

Solid or stranded aluminium alloy to SANS 1063 / IEC 62561-2
Minimum cross-section: 50 mm² for lightning protection
Lighter and more cost-effective than copper over long runs
Requires bi-metallic connectors at copper interfaces to prevent galvanic corrosion

High Voltage Conductors (HVC)

Proprietary insulated down conductor system for aesthetic and space-constrained installations
Conductors can be routed close to building surfaces without risk of flashover
Well suited to thatch roofs, heritage buildings, and architecturally sensitive structures
Compliant with SANS 62305-3 requirements for isolated lightning protection systems

Installation Standards We Follow

A down conductor’s performance depends as much on how it is installed as on what it is made from. HHK’s installation practices comply strictly with SANS 62305-3, which sets out requirements for:

Minimum number of down conductors per structure, based on building perimeter and protection level
Separation distance, the minimum clearance between the conductor and any building metalwork, to prevent side-flash
Routing: conductors follow the most direct path to earth, avoiding sharp bends that increase impedance
Mechanical protection: conduits or guards where conductors are vulnerable to impact
Jointing: all joints mechanically secure, electrically continuous, and corrosion-resistant
Test joints: accessible test joints at ground level for periodic resistance measurement
Fixing centres: conductors supported at defined intervals to withstand electromagnetic forces during a strike
Corrosion protection: material selection and protective finishes matched to the environment, whether coastal, industrial, or chemical

Supply Only Service

For contractors and in-house maintenance teams, HHK supplies high voltage conductors, connectors, fixings, and all associated components directly from stock across our eight branches. All materials come from approved manufacturers and comply with the relevant SANS and IEC standards. We provide technical data sheets, material certificates, and installation guidance with every supply.

Common Applications

New lightning protection installations for commercial, industrial, and residential buildings
Retrofit and upgrade of existing down conductor systems that no longer meet current standards
High-rise buildings requiring multiple parallel down conductors for current sharing
Explosive atmosphere zones in petrochemical and mining environments, where spark-free, high-integrity routing is essential
Thatch roof protection using HVC insulated down conductors
Infrastructure projects: bridges, telecommunication towers, wind turbines, solar farms

Every HHK installation includes a full test report and a legally recognised Certificate of Compliance — essential for insurance purposes and regulatory audits.

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Supply & Installation of High Voltage Conductors