Some Key Factors to Keep in Mind When Selecting Auto Fuses – WaytekWire.com
Because automobiles and their electrical systems are constantly evolving, there is a wide range of options when it comes to auto fuses. Selecting an auto fuse can be difficult, and you should probably seek some professional guidance before working on a specific vehicle’s electrical system. Understanding some key concepts, however, will help you have an intelligent and productive conversation with a professional about your auto fuse needs.
Blade fuses have a plastic body and two prongs that fit into sockets. They are commonly used in automobiles and can be mounted in a variety of ways. They are available not only in several amp strengths but also in four different sizes. Regular (ATC/ATO) blade fuses were developed in 1976 for low-voltage applications in vehicles providing anywhere from 1 to 40 amps. The difference between an ATC and an ATO fuse is that an ATC’s fusible link is sealed or “closed,” and an ATO fuse is “open,” meaning it has a small opening that exposes the fusible link to the air. Like all blade fuses, they are color-coded to indicate their amps. Some blade fuses also have an indicator light that glows brightly when the fuse is blown, which eliminates guess-work and increases efficiency even when blown fuses are located in hard-to-reach areas.
In the 1990s, mini fuses were developed so that more fuses could be installed in the same space. Low-profile mini (APS) fuses are similar to mini (ATM) fuses, but their low overall height allows for space and weight savings. They are typically used as replacement fuses in new vehicles. Maxi (APX) blade fuses are used when a high amperage circuit is required from 20-80 amps.
Glass fuses were used in the electrical systems of North American built automobiles up to 1981. Because the element is visible, they are easy to inspect. Their low breaking or rupture capacity make them suitable for low voltage applications. Their dimensions and characteristics must also comply with the Society of Automotive Engineers (SAE) standard J554. This means that all glass fuses are ?” diameter, and their lengths vary according to their ampere ratings. They also come in a variety of fast-acting and time-delay speeds (AGA, AGC, AGU, AGW, and AGW). There are also ceramic (MDA) fuses, which have a higher breaking and rupture capacity, making them suitable for high current and voltage circuits. They are opaque, which makes them more difficult to examine.
High amp (AMG) fuses are ideal for battery and alternator cables or other heavy gauge cables requiring ultra-high current protection. They are available in 100-250 amps and have a bolt down design, which makes them easy to mount in fuse holders. ANN and ANL limiter fuses are an economical alternative to the Class T fuses in a non-code installation. They provide high ampere ratings in a compact size. While both are ideal for heavy-duty applications, ANN fuses are available in 100-400 amps and ANL fuses are available in 60-300 amps.
These are just some of the factors involved with choosing the right auto fuse for a specific application. It is easy to feel like you are becoming lost in an alphabet soup, which is why it is essential to consult a professional before proceeding. The most important thing to keep in mind is that your choice of fuse is ultimately dependent on the voltage rating necessary to power and protect your circuit. You want to make sure you not only protect your vehicle’s electrical system from overheating, but also prevent oversensitivity that manifests in fuses blowing repeatedly for no practical reason. When provided with the necessary information, Waytek Wire will always ensure that you are selecting the appropriate fuses for each component of your vehicle’s electrical system.
John Brown is a retired mechanic who teaches courses in automobile electronics. If you would like to learn more about auto fuses, you may want to visit WaytekWire.com.