Choosing the Right Fuse

If you work with electrical systems, you are probably familiar with fuses. But if you don’t, fuses can be confusing.

Fuses protect circuits from overcurrent, overload and ensure the protection of the circuit. While all fuses have the same purpose, there are different types. It’s important to determine which fuse you need for a job before you start. If you choose the wrong type of fuse, it can lead to problems such as equipment damage, electrical fires and injuries.

Choosing the right fuse for a job can be tricky, but it doesn’t have to be. So how do you know which is the best to use? Here are some ways to choose the right fuse.

Type of circuit

Fuses can be classified into two main categories, alternating current (AC) and direct current (DC). DC fuses are typically used on circuits on vehicles and equipment, while AC fuses are used in building power systems and other higher voltage equipment.

Determine the voltage

The voltage rating of a fuse is determined by the maximum voltage the fuse can withstand before it breaks down. Determining the proper voltage rating is crucial for a circuit. Choosing a fuse with a voltage rating lower than the applied voltage can cause the fuse to fail or blow prematurely. 

Choose the correct rating

The current rating identifies the current that the fuse can carry under normal working conditions. Fuses come in different ratings, so it is important to choose a fuse with the right rating to avoid burning out the fuse. The current rating of a fuse can be obtained by calculating the expected current load and selecting a corresponding fuse.

When replacing fuses, always make sure to keep the current rating the same. Installing a fuse with a higher rating can lead to damage or electrical fires. 

Find the right size

To determine which fuse to use, you’ll want to size the fuse to its holder. Choosing the right size is necessary to ensure the fuse fits well in the designated holder.

Determine its use

Depending on the job at hand, you might need a specific fuse, such as automotive fuses. Fuses and holders like ANN, ANL and MEGA provide protection for high-current circuits. They can be used on things like batteries or charging systems, pallet jacks and other items that have high-draw electrical circuits. Meanwhile, general purpose automotive and equipment fuse boxes will often use ATO, ATM, low profile or JCase fuses.

Consider circuit breakers

When discussing fuses, you might also hear about circuit breakers. Circuit breakers and fuses serve a similar purpose but operate differently.

Inside a fuse, there is a metal ribbon that all electric current passes through. When a current exceeds a certain level it melts, which causes the fuse to open. This breaks the circuit and prevents the further flow of electricity. Fuses are for single use, so they need to be replaced if a system overloads.

Circuit breakers are switches that trip and open the circuit when a fault is detected, preventing damage. While circuit breakers are like fuses, the main difference is that circuit breakers can be used repeatedly and can be reset. This makes them ideal for applications prone to blowing fuses.

Circuit breakers are available in universal styles or common fuse series replacements that you can install directly into fuse blocks. Depending on the kind of circuit breaker, you can either reset them manually or automatically. It not only saves you time changing fuses, but it saves you money, as well.

If you're unsure about which type of fuse to use, it’s best to consult a professional. This will help you avoid any kind of mishaps. If you are confused about fuses, a Kimball Midwest sales representative can help. If you don’t already have a rep, we can help you