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How Circuit Breakers Fail Without Tripping

Circuit breakers are an essential device for countless electrical assemblies, serving to protect circuits and sensitive components from the harmful effects of surges, short circuits, etc. Circuit breakers are designed to be reusable, tripping when a fault is detected before being able to be manually reset. While circuit breakers are robust apparatuses designed to take on large surges, they will still face typical wear and tear, eventually failing under the stress of high current surges that come from various sources such as lightning, power line damage, etc. As the failure of a circuit breaker can lead to some hazardous situations for electronics and the people using them, it is important to have a general understanding of how circuit breakers fail.


Overloading is when the current surge entering the circuit breaker exceeds its overall rating. Overloading will not always cause an immediate breakdown, but it can greatly diminish the health of various inner components, leading them to lose functionality. When overloads are detected, it is important to determine all of the devices that are connected to the circuit that is managed by the breaker, seeing if there is an issue such as too many systems being linked. After measuring the total amperage in the circuit, the maximum continuous load should not exceed 80% of the breaker’s overall rating as to prevent overloading.

Damaged Switches

In order for a circuit breaker to effectively protect a circuit, it must be able to separate contacts and break the path of voltage through the circuit. If the circuit breaker is not tripping, no power is flowing through the circuit, and the switch is stuck in the ON position, then it is most likely a broken switch that will need to be checked by an electrician. Sometimes, this may necessitate the replacement of the entire circuit breaker device. Additionally, if there is a scorched path surrounding the breaker, then the issue may be something else.

Extreme Temperatures

When electricity dissipates, it often creates heat as a byproduct. When breakers trip to prevent flow, their various components may heat up. If temperatures are extreme, these components can melt down and break, rendering them useless. If a surge occurs and there is any smoke, burning odors, charred components, or other such signs of fire or heat damage, the circuit breaker will need to immediately be replaced. When a circuit breaker melts, one should never touch it before switching off the main breaker and waiting for components to cool.


As stated before, circuit breakers will face normal wear and tear, and even if major issues do not occur, standard use will eventually cause the death of the breaker. Typically, most circuit breakers have a lifespan ranging from thirty to forty years, the exact timing varying based on operating conditions and use. When a breaker becomes very old, it may face an issue where power turns off but the breaker does not switch. Often, corrosion or wear may deter the switch from being able to turn off in the face of an electrical abnormality, and this may lead to various unsafe conditions. If deterioration has reached the point where the circuit breaker is not able to trip, then it is time for a replacement to ensure the safety of the building, electronics, and all personnel around the circuit.

Best Approach When A Circuit Breaker Fails

When a failure occurs, regardless of the reason, it is important that one takes the correct steps to ensure safety. The first thing one should do is always to turn off the main power switch so that there is no power running through the building or area. Then, the main breaker should be powered off until the power has been restored, at which point the breaker can be activated again. Once that is completed, an electrician should be contacted while you handle any insurance needs, clock resets, and other requirements.


Whenever circuit breaker issues occur where parts need to be replaced, it is important that you tackle such needs as soon as possible to quickly get everything back up and running safely. Alpha Aerospace Parts is a premier purchasing platform for electrical parts of all types, presenting an inventory of over 2 billion new, used, obsolete, and hard-to-find components that have been sourced from leading global manufacturers that we trust. Leveraging our purchasing power and market expertise, we can fulfill your needs while ensuring competitive pricing and rapid lead times. Furthermore, we subject countless items to varying levels of quality assurance, guaranteeing that each purchase can be steadily relied on with ease. As you explore our website, take advantage of our Instant RFQ service to quickly and easily request quotes for your comparisons. Once we receive a completed form, a dedicated account manager will reach out to you in 15 minutes or less to present a customized solution based on your needs!


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