1. Disconnector: Used to isolate circuits or equipment, usually operated without load, to ensure that the equipment is not charged during repair or overhaul. Disconnectors cannot be used to disconnect load current, so they are often used in conjunction with load switches or fuses.
2. Load switch: It is used for cut-off operation under electric load, it can safely cut off a certain load current, but it is usually not suitable for cutting off large current or fault current.
3. High voltage fuse: used to protect equipment in the power system from damage caused by overload or short circuit. It is able to quickly fuse when the current exceeds the safe range, cutting off the current and thus preventing damage to the equipment. The voltage level of these devices (e.g. 3~500 kV) directly affects their design and use. High-voltage equipment needs to have strong insulation properties and stability to ensure reliable operation under different voltage and current conditions.
