Fuse vs. Circuit Breakers: What are the Differences?

A black and white circuit breaker with a close up of a tripped breaker.

Fuses and circuit breakers are both designed to ensure the safety of electrical circuits in a home. While both fuses and circuit breakers share similar characteristics, there are differences in functionality, resetting options, response time, and protection. Understanding the distinctions is important for all homeowners, especially when considering electrical wiring upgrades. Read the key differences between a fuse and a circuit breaker below: 

  1. Difference in Functionality: Both fuses and circuit breakers protect electrical components from exceeding their electric current threshold. Fuses are made much simpler and contain sacrificial components. When a fuse current generates heat, it begins to melt, resulting in a blown fuse. A circuit breaker can detect when there is an electrical overcurrent, which will result in a tripped circuit breaker. Circuit breakers are more complex and are built as an electromechanical mechanism.  
  2. Difference in Resetting: The key difference in resetting a circuit breaker is that you can manually push it back into place yourself. This will restore power safely. If your circuit breaker is not hot to the touch, you can push it back into place. If you find your circuit breaker always tripping or if there’s a burning smell, you should contact an electrician to inspect your circuit breaker panel. An electrician must immediately replace a fuse when it blows, unlike a circuit breaker, which can be reset. You can detect a blown fuse if an electric switch or device stops working.  
  3. Difference in Response Time/Speed: A fuse usually has a quick response time because of how quickly it melts the metal wire. Response time does depend on factors like the type of fuse and how large the electrical overcurrent is. Similarly, a circuit breaker’s response time depends on its type and design. Thermal magnetic circuit breakers are popular because they have a fast response time. The thermal component for this type of circuit breaker is designed to sustain overloads and the magnetic component can react quickly to any short-circuits. While both are designed to respond quickly, it ultimately depends on the type of fuse or circuit breaker installed to determine the speed of the response time. 
  4. Difference in Protection: A fuse protects homes and electrical devices from electrical overloads, whereas a circuit breaker can provide protection from overloads and short-circuits. Overloading happens when there’s too much current flowing in the electrical wires, resulting in the heating and melting of the wire. A short-circuit occurs when two conductors have different voltages, and the current will then take the path of least resistance.  

In Need of a Circuit Breaker Inspection or Fuse Replacement?

Milton Electric is a family-owned electrical service company in business since 1950. With years of experience and a variety of expertise, the team at Milton Electric is here to help with all your electrical needs. If you are experiencing any circuit breaker concerns and a blown fuse, contact certified electrician Milton Electric today at 410-680-3055.