How to do AC hipot test for low voltage(LV) cable based on the IEC standard?
The low-voltage cables need to be determined based on parameters such as cable type and rated voltage according to IEC standards (such as IEC 60502 series) when the cable factory conducts the AC hipot test.
1. Test voltage:
Based on the rated voltage of the cable (U0), the factory test voltage is usually 3.5 times U0 (for example, for a cable with a rated voltage of 0.6/1 kV, U0 = 0.6 kV, and the test voltage is 2.1 kV). This value is higher than the preventive test standard to verify the insulation performance at the time of factory production.
2. Test time:
The preventive test for AC hipot test of LV cable in China's GB 50150 adopts a voltage of 2.5 times U0 for 60 minutes, while based on IEC standard, for the LV cable factory places greater emphasis on short-term high-voltage verification (3.5 times U0 for 15 minutes) for factory acceptace test.
3. Test frequency:
Power supply in industrial frequency (50/60Hz) or variable frequency ranging from 20 to 300Hz. First to use the industrial frequency. If equipment is limited, then use the variable frequency, but ensure the waveform quality.