Why BS6622 Cables Matter in South Africa

If you work in South Africa’s mining, utility, industrial, or renewable energy sectors, you know that medium-voltage (MV) reliability is non-negotiable. Power dips shut down conveyor belts, overheating cables halt mining ventilation systems, and insulation failures trigger costly substation outages. In some mining operations, a single hour of downtime can cost more than R1 million.

That’s exactly why BS6622 medium-voltage armoured cables (3.8/6.6kV to 19/33kV) have become a backbone of South African MV distribution. Designed for durability, thermal stability, and mechanical strength, they operate reliably in environments that include:

• Limpopo’s rocky platinum belts

• Northern Cape solar fields

• KZN’s humid coastal industrial zones

• Gauteng municipal substations

• Deep shaft mining networks in Rustenburg

South Africa’s harsh conditions—heat, UV, chemical soils, impact forces, rodent activity, and high fault levels—demand more than average cables. BS6622 MV cables deliver that toughness.

These cables dominate 11kV, 22kV, and 33kV distribution networks due to:

• Globally trusted British cable engineering

• Long-term stability under thermal and electrical stress

• Mechanical protection through SWA/AWA armouring

• Compatibility with SANS 10198 installation practices

Understanding the BS6622 Standard

Scope of BS6622

BS6622 is the reference standard for armoured medium-voltage power cables used in fixed installations. It covers:

• Voltage classes: 3.8/6.6kV → 19/33kV

• Cables for substations, industrial plants, mines, and distribution networks

• Single-core AWA (Aluminium Wire Armour)

• Three-core SWA (Steel Wire Armour)

In other words, these are the “workhorse” cables that feed South Africa’s MV grid.

Types of Cables Covered

BS6622 includes multiple constructions, such as:

• XLPE/PVC/SWA/PVC

• XLPE/PVC/SWA/MDPE

• XLPE/AWA/PVC for single-core feeders

• EPR-insulated variants for high-temperature or chemical resistance needs

Single-core cables → typically aluminium armour (AWA)
Three-core cables → galvanised steel wire armour (SWA)

Key Compliance Tests Required by the Standard

Every BS6622 cable must pass strict IEC-aligned testing, including:

• Electrical strength / HV withstand tests

• Insulation and sheath integrity

• Armour fault current capability test

• Hot set test (for thermoset insulation)

• Fire behaviour tests (including CPR for PVC sheaths)

• Water penetration, corrosion & ageing resistance

This makes BS6622 one of the most dependable MV cable standards for long-term installations.

Cable Construction Explained (Layer-by-Layer)

The design of a BS6622 cable is what gives it strength, stability, and reliability.

Conductor

Options include:

• Copper Class 2 stranded — preferred in:

  Mining

  Substations

  High mechanical load applications

• Aluminium Class 2 stranded / Class 1 solid — preferred in:

  Long feeders

  Renewable collector systems

South African trend:
CU for critical loads | AL for long-distance cost-efficient feeders

Insulation (XLPE or EPR)

• XLPE (GP8) – the most common

  90°C operating temperature

  Low dielectric loss

  Excellent ageing performance

• EPR (GP7) – selected for:

  Marine/coastal plants

  Chemical processing facilities

  High thermal overload capability

Insulation Screen

A semi-conductive extruded layer that ensures:

• Uniform electric field distribution

• Reduced partial discharge (PD)

• Improved long-term dielectric stability

Metallic Screen

Made from copper wires or copper tape.

Functions:

• Carries earth fault current

• Reduces electromagnetic interference (EMI)

• Provides a return path for protection devices

Inner Sheath (Bedding)

• Usually PVC

• Separates the armour from the inner layers

• Adds mechanical cushioning

Armour Layer (AWA or SWA)

AWA – Aluminium Wire Armour

Used for single-core cables because:

• Reduced eddy current losses

• Non-magnetic behaviour

SWA – Steel Wire Armour

Used for three-core cables:

• Highest mechanical protection

• Excellent crush and impact resistance

• Essential in:

  Mines

  Construction zones

  High-vandalism areas

Outer Sheath Options

PVC

• Indoor installations

• CPR compliant

• Good fire characteristics

MDPE (Medium-Density Polyethylene)

• Superior abrasion resistance

• Chemical and moisture resistant

• Best for direct burial, especially in:

  Free-draining soil

  Rural feeders

  Renewable energy plants

Voltage Ratings and System Categories

Understanding Categories A, B, and C

BS6622 defines systems based on how faults are managed.

Choosing the Right Voltage Rating

South African examples:

• 6.35/11kV (12kV) – municipal feeders, substations

• 12.7/22kV – industrial zones, mines, processing plants

• 19/33kV – solar/wind collector systems, long-distance distribution

South African Environmental Considerations

• High daytime temperatures → XLPE withstands 90°C and overloads

• Rocky or compacted soils → SWA armour essential

• Chemical soils → MDPE outperforms PVC

• UV-intensive environments → MDPE again preferred

• Vandal-prone areas → Steel armour adds protection

Typical BS6622 Cable Models and Their Real Applications

BS 6622 CU XLPE AWA/SWA PVC 3.8/6.6kV

Used for:

• Light industries

• Smaller substations

• Local distribution upgrades

BS 6622 XLPE PVC 6.35/11 (12) kV Cable

The most widely used MV cable in South Africa.

Installed by:

• City Power Johannesburg

• Tshwane Municipality

• eThekwini Municipality

Seen in:

• MV ring networks

• Distribution substations

• Underground reticulation in estates

BS 6622 XLPE PVC 12.7/22kV Cable

Used for heavy electrical loads such as:

• Mining ventilation fans

• Large conveyor systems

• Industrial plants

• Water pumping stations

BS 6622 XLPE MDPE 19/33kV Cable

Increasingly popular in renewable energy:

• Wind farms

• Solar farms

• Collector lines

• Transmission tie-ins

Technical Specifications and Electrical Parameters

A complete BS6622 MV cable specification includes:

• Conductor sizes: 35 mm² to 630 mm²

• Current-carrying capacity: varies by installation method

• Short-circuit ratings: thermal withstand for 1 second

• Minimum bending radius:

  Typically 12 × diameter for armoured cables

• Armour fault-current capability

• Dielectric strength test examples:

  11kV cable → tested at ~24kV AC

  33kV cable → tested at ~70kV AC

Installation Considerations in South Africa

Direct Burial

Challenges:

• High soil resistivity

• Rocky terrain

• Termites & rodents

• Moisture variation

MDPE sheaths perform best outdoors.

Installation in Air or Cable Ladder

Important factors:

• Ventilation

• Support spacing

• UV-resistant sheaths

• Surge/EMI in industrial zones

Use in Mines

Why SWA/XLPE is preferred:

• High mechanical stress

• Mobile machinery movement

• Elevated temperatures

• Copper conductors handle overloads better

Safety and Compliance

Follow:

• SANS 10198 (South African installation standard)

• Proper earthing and bonding

• Fire performance checks in indoor applications

South African Case Study

11kV BS6622 Cable Upgrade in a Limpopo Platinum Mine

Problem

A platinum operation in Limpopo suffered:

• Frequent voltage drops

• Repeated insulation failures

• MV tripping during peak loads

Old PVC-insulated feeders were buried in rocky soil and damaged by loaders and haul trucks.

Solution

Upgrade to:

BS6622 CU XLPE/SWA/PVC 6.35/11kV cable
Installed via direct burial with protective bedding.

Results

• 28% reduction in unplanned downtime

• Fault clearance aligned with protection curves

• Armour prevented further mechanical failures

• Improved power stability for ventilation and dewatering pumps

Lessons

• SWA armour is essential in mining

• XLPE insulation prevents thermal ageing

• Upgrading cables directly boosts productivity

Advantages of BS6622 Cables for South African Users

• High mechanical durability

• Excellent thermal performance of XLPE

• Compatible with 11kV / 22kV / 33kV networks

• Wide selection of constructions (PVC / MDPE / SWA / AWA)

• Long lifespan even in harsh environments

• Recognised globally → simplified procurement and compliance

• Lower failure rates → lower OPEX

Limitations and Practical Considerations

• Heavier than unarmoured cables

• Requires MV-qualified jointers/terminators

• Not suitable for mobile equipment in mines (use SANS mining trailing cables)

• Requires correct bedding for rocky terrain

FAQ

Q1: What is the difference between AWA and SWA armour?

AWA = aluminium, for single-core
SWA = steel, for three-core
AWA avoids eddy current heating.

Q2: Can BS6622 cables be used in underground mines?

Yes — but only for fixed installations, not mobile machinery.

Q3: Is MDPE better than PVC in South Africa?

Yes, for outdoor burial.
PVC is better for indoor installations.

Q4: What voltage levels does BS6622 cover?

From 3.8/6.6kV to 19/33kV.

Q5: Are BS6622 cables compatible with SANS requirements?

Yes — they integrate fully with SANS 10198 installation practices.

Q6: Are BS6622 cables suitable for renewable energy?

Absolutely — 22kV and 33kV BS6622 cables are widely used in solar and wind plants.

Conclusion

BS6622 remains one of the most trusted MV cable standards in South Africa. Whether you are powering a mine, utility network, or renewable energy project, these cables provide:

• Mechanical durability

• Thermal and electrical stability

• Long service life

• Wide adaptability

• Installations proven across South Africa

Selecting the right construction—PVC or MDPE, AWA or SWA, copper or aluminium—ensures safe, reliable, low-maintenance MV performance for decades.

Contact Anhui Feichun Special Cable Co., Ltd.

For comprehensive technical specifications and quotations, please contact our specialized mining cable engineering team:

Technical Engineering Support:

tech@feichuncables.com

Sales Engineering Department:

Li.wang@feichuncables.com

WhatsApp Contact:

Manufacturer: Anhui Feichun Special Cable Co., Ltd. (安徽飞纯特种电缆有限公司)

Manufacturing Headquarters: Building A, Private Science and Technology Park, Hefei Economic and Technological Development Zone, Anhui Province, People’s Republic of China

+86 17333223430