Post-Type Fuseholders

Post-type fuseholders are made for cartridge fuses. The post-type fuseholder is much safer because the fuse and fuse connections are covered with insulating material. The disadvantage of the post-type fuseholder is that the fuse must be removed to visually check for an open. The post-type fuseholder has a cap that screws onto the body of the fuseholder. The fuse is held in this cap by a spring-type connector and, as the cap is screwed on, the fuse makes contact with the body of the fuseholder. When the cap and fuse are removed from the body of the fuseholder, the fuse is removed from the circuit and there is no danger of shock or short circuit from touching the fuse.

Post-type fuseholders are usually mounted on the chassis of the equipment in which they are used. After wires are connected to the fuseholder, insulating sleeves are placed over the connections to reduce the possibility of a short circuit. Notice the two connections on the post-type fuseholder of figure 11. The connection on the right is called the center connector. The other connector is the outside connector. The outside connector will be closer to the equipment chassis. (The threads and nut shown are used to fasten the fuseholder to the chassis.) The possibility of the outside connector coming in contact with the chassis (causing a short circuit) is much higher than the possibility of the center conductor contacting the chassis. The power source should always be connected to the center connector so the fuse will open if the outside connector contacts the chassis. If the power source were connected to the outside connector, and the outside connector contacted the chassis, there would be a direct short, but the fuse would not open.