Cable faults refer to damages within cables that increase their resistance and, if left unaddressed, can lead to dangerous voltage breakdowns. Identifying the type of fault is crucial before locating and addressing the issue, with insulation playing a key role.

Paper-insulated cables, for example, are highly vulnerable to chemical and thermal impacts, while in high-voltage XLPE cables, damage to the polyethylene insulation results in partial breakdowns and cracks that gradually degrade the insulation.

For as long as cables have existed, so have cable faults. Over time, methods for locating these faults have evolved with technological advancements.

Initially, sectionalizing was the primary technique used. Technicians would measure the cable, cut it at the halfway point, and perform an Insulation Resistance test to identify the faulty section.

However, sectionalizing had several disadvantages:

1. The numerous joints reduced the cable’s overall lifespan.

2. The process of digging and jointing made fault detection time-consuming.

3. Repairing the cable afterward was expensive due to the jointing process.

During this period, the first fault location bridges, known as Murray Loop Bridges, were introduced to the market. By the 1960s, Time Domain Reflectometer (TDR) devices became available in South Africa. Although early versions looked quite different from today’s models, the underlying technology has remained largely unchanged.

Common Causes of Cable Failure:

• External damage
• Electrical spikes and overloading
• Environmental conditions
• Poor workmanship
• Aging cables

Cable Repairs May Involve:

• Jointing a new section of cable using LV or MV cable joints.
• Installing new LV or MV cable terminations.

By utilizing these advanced techniques and tools, we ensure accurate fault location and efficient repairs, extending the lifespan of your electrical infrastructure.