What are the procedures and tasks required while detecting a fault in a medium-voltage power cable

 What are the procedures and tasks required while detecting a fault in a medium-voltage power cable

Checking a malfunction in a Medium Voltage Cable requires precise measures because the risks are high (snapping - electric bracket - explosion). Therefore, the steps of an organization that combines safety and technical diagnostics must be followed.

🔴 First: Safety measures (most important)

Before any work:

• Whole nutrition class (Isolate)

 • تطبيق نظام Lock Out / Tag Out (LOTO)

• Ensure there is no effort using a certified testing device

• Temporary grounding work for cable (Earthing)

• Wearing preventive missions:

• Insulating gloves

• Helmet

 • Arc Flash Suit

• insulating shoes

🟡 Secondly: Fault Location

The type and location of failure are determined using specialized devices:

1. The preliminary tests

• Measurement of Resistance (Continuity Test)

• Measuring the resistance of isolation using Megger

• Determining if the break is:

 • قصر (Short Circuit)

• My Earth (Earth Fault)

• Cut in the cable (Open Circuit)

2. Vacation Locators

 • TDR (Time Domain Reflectometer)

To determine the approximate distance of the break place

 • Thumper Test

To establish a pulse and locate sparks

 • Cable Route Locator

To determine the path of the underground cable

🔵 Third: locating the location of the break with field accuracy

• Using headphones (Acoustic Method)

• The use of thermal cameras (if the cable is still partially loaded)

• Dig carefully in the expected location

‪4th: Fixing the break

Depending on the type of break:

• Replacing the damaged part of the cable

• Making a Joint (link) using:

 • Heat Shrink

 • Cold Shrink

• Ensuring the quality of isolation and the tightness of connection

🔵 Fifth: Tests after Reform

Before the restart:

• Insulation Resistance Test (IR Test)

• Hi-Pot Test (High Voltage)

• Connector continuity test

• Ensure there is no leakage or weak isolation

⚫ 6th: Restart (Energization)

• Removal of temporary grounding

• Remove the LOTO

• Gradually re-feed

• Cable and load monitoring

📌 Important notes:

• Medium-voltage cables are not operated without a work permit (Permit to Work)

• It is preferable to have a cable path chart (As-built drawing)

• Recording all readings and results for future maintenance purposes

• In case of repeated failures, a review should be:

• The quality of installation

• Overloads

• Soil conditions (humidity - heat) #safetywithbasit #permittowork #ExcavationSafety #safetyofficer #EHS #safetyculture #tbt #healthandsafety #safetyawareness #workplacesafety