- Type Tests Definition: Type tests ensure the quality and standards of electrical power cables by assessing various physical and electrical properties.
- Acceptance Tests: Acceptance tests verify that a batch of cables meets the required specifications through mechanical and electrical tests.
- Routine Tests: Routine tests are regular checks to maintain consistent quality and performance of electrical cables.
- High Voltage Test: This test involves applying high voltage to the cable to ensure its insulation can withstand extreme conditions.
- Cable Testing Importance: Cable testing is crucial for ensuring the safety, reliability, and longevity of electrical power systems.
- The following tests are the type test of electrical power cable.
- Persulphate test (for copper )
- Annealing test (for copper)
- Tensile test (for Aluminium)
- Wrapping test (for Aluminium)
- Conductor resistance test (for all)
- Test for thickness of insulation (for all)
- Measurement of overall diameter (where specified)(for all)
Physical tests for insulation and sheath
- Tensile strength and elongation at break
- Aging in an air oven
- Aging in air bomb
- Aging in an oxygen bomb
- Hot set
- Oil resistance
- Tear resistance
- Acceptance test: The following shall constitute acceptance test:
- Annealing test (for copper)
- Tensile test (for Aluminium )
- Wrapping test (for Aluminium )
- Conductor resistance test
- Test for the thickness of insulation and sheath and overall diameter
- Tensile strength and elongation at break of insulation and heath
- Hot set test for insulation and sheath
- High voltage test
- Insulation resistance test
- Routine test: The following shall constitute the routine test.
- Conductor resistance test
- High voltage test
- Insulation resistance test
High Voltage Test (Water Immersion Test) :
A 3-meter-long core sample is taken from the finished cable or cord. The sample is immersed in a water bath at room temperature, with the ends protruding at least 200 mm above the water. After 24 hours, an alternating voltage is applied between the conductor and the water. The voltage is increased within 10 seconds and held constant for 5 minutes. If the sample fails, another sample is tested.
Test on completed cables (Acceptance and routine test) :
These tests are conducted between conductors or between conductor and screen/armor. They are performed at the required voltage, at room temperature, and for a duration of 5 minutes, ensuring no insulation failure.
Flammability Test :
Period of burning after removal of the flame shall not exceed 60 sec and the unaffected portion from the lower edge of the top clamp shall be at least 50 mm.
