Test methods for portable short-circuit grounding wires

1; Visual inspection

Check whether all components on the visual side meet the usage requirements, whether the cross-section of the multi-strand wire is consistent with the markings, and whether the connection method is correct.

2.  Voltage drop test for group short-circuit grounding wires

 &Nbsp; Conduct a test on the assembled short-circuit grounding wire (on any branch of each wire clamped to another wire), apply 0.2% of the rated short-circuit current value, and measure its voltage. The voltage should be less than or equal to the voltage of the same length and cross-section stranded wire, or the voltage should not exceed 115% of the voltage measured during the type test

  3.  Fatigue Test of Multi Strand Flexible Conductors

 &Nbsp&Nbsp&Nbsp; One end of the tested multi-strand flexible wire is fixed on the test attachment, with a pole length of 100mm. The length of the tested multi-strand flexible wire is 1000mm. During the test, the test attachment swings back and forth along the axis, with a swing angle of 60 ° left and right. The lower end of the tested multi-strand soft wire is connected to a vertical guide piece and a load is suspended. The load is applied in a ratio of 50g/m2 of the wire cross-section. When the test attachment swings, the tested wire can be twisted back and forth along the loose strand direction by 90 °. The duration of the test is not less than 5s per week, and 1000 tests are conducted

 &Nbsp&Nbsp&Nbsp; After the test is completed, if the protective layer of the wire does not crack or fold, and the wire is disassembled and inspected, the number of damaged wire strands does not exceed 1%.

, it is considered that the test has passed

 &Nbsp&Nbsp&Nbsp; When checking the number of broken strands, the insulation layer of the wire must be peeled off and carried out in the case of loose strands

  4.  Grip force test between wire nose (busbar clamp) and multi strand flexible wire

 &Nbsp&Nbsp&Nbsp; Whether the gripping force between the test wire nose (busbar clamp) and the multi-strand flexible wire meets the requirements, and the length of the tested flexible wire should not be less than

300mm. During the test, it is important to avoid twisting the wires as much as possible Apply I0N/on the sample; Apply a uniform tensile force at a speed of (mm2 · s) to the values specified in Table 6-5, and continue at this value for 30 seconds. If there is no looseness in the connecting part, the test is considered to have passed