Item | 66kV | 110kV | 220kV |
Partial discharge | 72kV, partial discharge not more than previously carried out items | 96kV, partial discharge not more than previously carried out items | 190kV, partial discharge not more than previously carried out items |
Power frequency withstand voltage | 120kV/30min (joint main body 60min, no flashover no breakdown) | 160kV/30min (joint main body 60min, no flashover no breakdown) | 318kV/30min (joint main body 60min, no flashover no breakdown) |
Seal test | 0.25±0.01MPa/1h for sealing fittings, porcelain bushing, composite bushing, no leakage |
0.6~0.7MPa/1h for epoxy bushing, no leakage |
Appearance test | No damage, no cracking and other defects that affect the quality and appearance |