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33kV Cable Testing Before Termination

The cable used was:  

📌 Type: 33kV / 3C / 240mm² / XLPE  Before termination, we conducted several critical tests: 

✅ 1. Visual Check  

🔹 Verified all electrical installations against approved drawings.  

🔹 Inspected cables for physical damage before testing. 

⚡ 2. Cable Outer Sheath HV Test  

🔸 Equipment- 10kV Insulation Resistance (IR) Tester  

🔸Test procedure,  

🔹Both ends of the cable conductors were isolated from all connections.    

🔹 Removed outer sheath, armour, metallic screens, and XLPE insulation semi-conductive layer.    

🔹 Removed an additional 10-15 mm of the outer sheath semi-conductive layer at both ends.    

🔹 Connected the +ve lead of the IR tester to the cable armour and the -ve lead to the outer sheath.    

🔹 Applied 5kV DC for 1 minute and recorded the readings.    

🔹 Discharged the metallic sheath to the ground using a resistor rod.    

🔹 Ensured the test area was barricaded for safety.  

✅ Passing Criteria- Above 2 MΩ – Cable is in good condition for termination. 

🔍 3. Conductor Insulation Resistance (IR) Measurement Test  

Step 1: Core to Earth Test  

🎯 Purpose: Verify insulation resistance (IR) of individual phase conductors (R, Y, B) before termination.  

🔸 Equipment: 10kV Insulation Tester  

🔸Test procedure,   

🔹 Both ends of the cable were isolated from all connections and grounded.  

 🔹 Removed the outer sheath, armour, metallic screens, and XLPE insulation semi-conductive layer.     

🔹 Connected the +ve lead of the IR tester to the Red core, and the -ve lead to the ground.    🔹 Grounded the Yellow & Blue cores, outer sheath, inner sheath, and cable armour.     

🔹 Applied 5kV for 1 minute, then discharged the cable and recorded the IR reading.  

  🔹 Repeated for Yellow and Blue cores. 

Step 2: Core to Core Test   

🎯 Purpose: Measure insulation resistance between phase conductors.    

 🔹 R core and Y core connect to IR tester. Core of B ,conductor screen and armour grounded using  jumper leads.

Apply 5kv,one minute and record Insulation Resistance. Do the same for R-B, and Y-B.   

✅ Passing Criteria- Above 2 MΩ – Cable is in good condition for termination. 

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