Cartridge fuses are type of electrical fuse used to protect circuits and equipment from overloads. They are cylindrical in shape, similar to a light bulb, and screw into a matching socket. Cartridge fuses are typically used on industrial equipment and as a protection device in larger residential and commercial applications. Cartridge fuses contain a conducting wire encased in an insulating material and they come in various sizes and amp ratings. They have the ability to detect and respond quickly to current flow in a circuit, protecting against damage from current overloads and short circuits.