Primary Uses of Drop-out Fuses

1. Protection of Distribution Transformers: Installed on the high-voltage side of a transformer, the fuse link melts and interrupts the current in the event of an overload or short circuit, thereby preventing damage to the equipment.

2. Protection of Line Branches: Used at the beginning of branch lines within 10kV distribution networks to protect the lines from short circuits or overloads.

3. Switching Load Current: In the absence of a dedicated switch, these units can serve as temporary switches for making or breaking rated load currents (e.g., when interconnecting two lines).

4. Fault Indication: Once the fuse tube drops, it creates a visible break in the circuit, allowing operations and maintenance personnel to quickly locate the fault.

Precautions for Drop-out Fuses

• Strictly prohibit opening or closing the fuse unit while it is under load to prevent arc burns or equipment damage.
• When operating in rain or snow, use an insulated operating pole equipped with a rain shield; do not perform operations during thunderstorms.
• If any abnormalities are observed (such as overheating, smoke, or arcing), immediately disconnect the power supply and investigate the fault.