8.7/15 kV12/20 kV / 18/30 kV / 26/35 kV
5 min power-frequency withstand voltage test39 kV / 54 kV / 81 kV / 117 kV
Partial discharge test15 kV / 20 kV / 30 kV / 45 kV
Load cycle test in air22 kV / 30 kV / 45 kV / 65 kV
Load cycle test in water22 kV / 30 kV / 45 kV / 65 kV
Impulse voltage test95 kV / 125 kV / 170 kV / 200 kV
Maximum allowable temperature during normal operation90°C / 90°C / 90°C / 90°C
Maximum allowable temperature during short circuit250°C / 250°C / 250°C / 250°C
Test itemStandard requirement / Test result / Conclusion
1 min power-frequency withstand voltage test4 kV, no flashover, no breakdown / 4 kV/1 min, no flashover, no breakdown / Pass
Load cycle test (three cycles)5 h heating, 3 h cooling, conductor temperature 75°C during heating / assessed by the following / Pass
4 h power-frequency withstand voltage test2.4 kV, no flashover, no breakdown / 2.4 kV/4 h, no flashover, no breakdown / Pass