If you’ve ever heard a loud bang during a storm and thought a transformer exploded, it was likely a cutout doing its job. A cutout, also called a fuse cutout, is a protective device mounted high on a power pole near transformers or along primary distribution lines. Its purpose is to protect electrical equipment from current surges and overloads caused by lightning, storms, vehicle accidents, or where there is high energy use.

Inside the device is a fuse designed to melt when electrical current becomes unsafe. When it operates, the fuse barrel drops open, disconnecting the line and stopping the flow of electricity to prevent further damage. The sharp “shotgun” sound people sometimes hear is the fuse activating, a sign the system is working to isolate a problem and protect equipment.

While the noise can be startling, it’s often a sign that the system is functioning exactly as it should.