Technical insight

Cable Fault Location Methods: A Practical Overview for Project Teams

Fault response is usually a chain: identify the fault, excavate safely, repair correctly, then test and return to service. This page explains common fault location approaches at a high level, and how to plan the repair activity once the location is confirmed.

If you need support with a HV fault, see HV Fault Response.

What the project team needs to know

  • Fault location is about narrowing down where to excavate
  • Access, permits and isolation arrangements often drive the timeline
  • Repair quality matters more than speed if you want reliability after re-energisation

Common fault types

  • Third-party damage
  • Joint failure
  • Termination failure
  • Insulation breakdown due to age or defects
  • Water ingress and sheath issues

Planning the repair once the fault is located

  • Confirm cable type and joint specification before the outage
  • Ensure excavation is safe, stable, and provides working space
  • Protect the work area from moisture and contamination
  • Plan for testing and energisation handover

The fastest repairs happen when the scope is confirmed early and the site is prepared properly.

Related services

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