Types of Automotive Electrical Fusesby Rebecca Burdick
A fuse is a device designed to protect an electrical system against damage. It protects against overheating, which can cause fires, and overloading, which can damage electronic components. Its primary function is to limit amperage. This is accomplished by either creating a section of higher resistance, or a section with a lower melting point than the rest of the electrical system. Using fuses ensures that the fuse fails before anything else.
Standard Blade Fuses
The standard blade fuse is the most commonly used type of fuse for automotive purposes. These fuses are made to burn out at a specific amperage. Different companies manufacture fuses for different amperage ratings, but they can be found ranging from 1 to 40 amps. You are most likely to find these fuses under the dashboard of your car controlling the interior electrical circuits of your car. A simple measurement will tell you if you have a standard blade type fuse because it will be roughly 19 by 5 by 18 mm. This is only an approximation since all manufacturers vary slightly. However all fuses are significantly different in size. The fuses are transparent or translucent in order to allow you to see whether or not the fusible section is burned or not. They are recognizable by two blades that are designed to plug into the fuse panel.
Mini Blade Fuses
Mini blade fuses are a variation on the standard blade fuse. They look nearly identical to the standard blade fuses, but are obviously smaller. These fuses are generally not manufactured with the same variety as a standard fuse, but you might encounter them ranging from 2 to 30 amps. The purpose on the mini blade fuse is simply to fit more fuses into a smaller fuse box. A simple measurement should show the fuse to be about 11 by 4 by 16 mm.
Maxi Blade Fuses
Maxi blade fuses are a variation of the standard blade fuses. These are obviously larger, and are usually found in the fuse box under the hood of your car. They can handle more current, and you may find them ranging from about 20 to 100 amps. If your fuse measures about 30 by 9 by 35 mm, it is most likely a maxi blade fuse. These fuses control high power operations of the vehicle such as the starter.
Glass Tube Fuses
Glass tube fuses come in all shapes, sizes and amperage ratings. They can be recognized by the metal caps on both ends of the glass tube, with a wire running down the center of the tube. The amperage rating will be marked on the metal ends. They are typically used in older vehicles and circuits.
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- "Automotive Electrical Systems"; Vaughn D. Martin; 1999
- "Automotive Electrical Handbook"; Jim Horner; 1987
- car fuses image by Witold Krasowski from Fotolia.com