A load break switch is a switching device positioned between a circuit breaker and an isolation switch. It is equipped with basic arc-extinguishing mechanisms, enabling it to interrupt normal load currents and certain levels of overload currents. However, it cannot handle short-circuit currents. The load break switch is capable of switching on and off load currents, excitation currents, charging currents, and capacitor bank currents under normal operating conditions.

Types of High Voltage Load Break Switches:

1. Vacuum High Voltage Load Break Switch

   • Utilizes a vacuum medium for arc extinction, offering a long electrical lifespan.
   • Typically more expensive, suitable for systems operating at 220 kV and below.
   • Examples: FZN25, FZN21, FZN64 series.

2. Oil-Immersed High Voltage Load Break Switch

   • Relies on the arc's energy to decompose and vaporize surrounding oil, which cools and interrupts the arc.

3. Sulfur Hexafluoride (SF₆) High Voltage Load Break Switch

   • Uses SF₆ gas to extinguish the arc, enabling it to handle larger breaking currents and perform well in breaking capacitor currents.
   • Features a relatively complex structure, suitable for systems operating at 35 kV and above.
   • Example: FNL36 series.

4. Compressed High Voltage Load Break Switch

   • Employs the piston’s compressed air during the breaking process to blow out the arc.
   • Simple in structure, suitable for systems operating at 35 kV and below.
   • Example: FKN12 series.

5. Solid Gas-Generating High Voltage Load Break Switch

   • Uses the arc’s energy to generate gas from materials in the arc chamber, which extinguishes the arc.
   • Simple structure, suitable for systems operating at 35 kV and below.
   • Example: FN5 series.

6. Compressed Air High Voltage Load Break Switch

   • Uses compressed air to extinguish the arc, capable of interrupting large currents.
   • Features a relatively complex structure, suitable for systems operating at 60 kV and above.

This summary highlights the key features and application ranges of different types of high voltage load break switches, aiding in the selection of the appropriate device for specific system requirements.