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What Causes a Circuit Breaker to Go Bad? – 4 Main Reasons

Written by Edwin Jones / Fact checked by Andrew Wright

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In most cases, short circuits, spikes, power surges, circuit overloads, and conduit systems with grounded wires are what causes a circuit breaker to go bad. Of course, you should also consider the possibility of the circuit breaker becoming damaged and not working altogether.

I’ll explain how each of these factors affects circuit breakers in the following post. I’ll also throw in a couple of tips on how you can solve these circuit breaker malfunction issues should they arise in your home or business.

The Primary Reasons Why a Circuit Breaker Fails

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Many electricians will agree that the four reasons I mentioned above are what you should immediately consider if you suddenly have a faulty breaker. At most, when people say they have a “bad circuit breaker”, it’s because it trips constantly. The first thing that goes through my mind when people mention that is a possible overload, ground fault, or short circuit. You can click here to learn more how to fix fix short circuits.

Circuit breaker failure causes are as varied as they are distinct from one another. It’s well worth taking the time to know how each one affects a breaker, or worse, causes it to fail. This allows you to quickly and properly diagnose the problem and make a timely decision from there.

After all, circuit breakers play a pivotal role in keeping your electrical system safe. It trips to safeguard you from the potential damage caused by short circuits and overloads. If it has gone bad, what will give you that protection?

Anyway, here’s how the said problems go about in most broken-down breakers.

1. An isolated power surge or spike causes it to malfunction

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These are spikes that happen because of lightning or the presence of static electricity nearby. You may even encounter them when you overuse your extension cords or use devices that are well above your circuit’s amperage capacity. The short nanosecond they happen is enough to affect breakers negatively.

Sadly, most circuit breakers can’t handle this surge. You’ll have to rely on a dedicated surge protector, which requires its own breaker, to shield your electrical appliances from these surges. However, this protection isn’t always guaranteed. Your breaker and appliances can still be damaged by lightning, for instance.

2. A short circuit happens

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If electricity deviates from its intended path, a short circuit occurs. For example, currents that are running on a hot wire suddenly enter a neutral one.

Why is this dangerous? The overall resistance dips almost the second it happens. Decreased resistance means a huge volume of current flows through that unintended wire.

Anything in its path can be toasted, so expect the breaker to trip once it kicks in. Expect it to keep tripping even after you try to reboot it. This is why you’ll often see smoke and even fire if a short circuit happens, and there’s no breaker to protect your circuits.

Want to dive deeper into the science of common circuit breaker problems like short circuits and overloads? This video presents the subject in a more academic approach. I also like how each concept is presented, so if you have time, don’t hesitate about viewing it:

3. You’re dealing with ground faults

Grounded wires are as common in residences as in conduit systems for industrial and commercial buildings. They happen because wires touch materials they shouldn’t, like metal or another ground wire. They can be especially dangerous in rooms with plenty of moisture, such as kitchens and bathrooms.

On the whole, these faults are similar to short circuits. They’re also called hard shorts because they’re characterized by a sudden rise in the flow of electricity as a result of the resistance dramatically dipping.

4. You overload your circuits

Have you ever encountered a circuit breaker that trips because you turned on plenty of devices and appliances? That’s how a circuit overload typically happens. I won’t be surprised if you’ve had this happen to you at least once in your life considering it’s the most common reason why circuits trip.

The heat serves as the main reason why breakers do this. Once it reaches that threshold, it promptly stops the flow of electricity. What’s good is that this problem rarely does lasting damage to the circuit breaker.

Check the State of Your Wires Too

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While I consider the four issues above as the most probable causes of botched circuit breakers, I can’t ignore the fact that breakers tend to be affected by wrong wiring as well. Be on the lookout for loose wires, especially in your electrical box.

Most of the time, this happens because the person who worked on the wire didn’t tighten the terminal screw enough. Be extra careful of loose connections! To me, they often mean more heat is being produced throughout the circuit. As this heat builds up, it will inevitably cause the circuit breaker to trip.

Is It Possible for a Breaker to Just Stop Working

Circuit breakers may be known for their longevity, but there’s always a chance for them to suddenly stop working. Tell-tale signs your breaker is about to break are:

  • It feels constantly hot to the touch.
  • There are evident signs of damage or scorching.
  • It’s beginning to trip more than usual.
  • It’s emitting a distinct electrical odor.

If this happens, you should contact a professional electrician right away to discuss its replacement. Feel free to ask him or her about what may have caused it to fail to function suddenly. Incidentally, this leads us to the second arguably important question.

Can a Circuit Breaker Fail without Tripping

Unfortunately, yes. I attribute this problem to when the breaker gets exposed to too much heat that it can’t handle over time. Sometimes, it’s even caused by low voltage.

If you ignore this problem, you’re essentially playing dice with your electrical system since there’s no breaker protecting it.

How Should You Identify These Problems

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These are some of the efficient ways I diagnose circuit breaker problems.

  • For short circuits and spikes, you want to look at the scenario I pointed out above. If the breaker fails to reboot and keeps tripping, you’re probably facing this problem. Short circuits are actually one of the hardest ones to pinpoint because they have the same signs as broken breakers.
  • I also like to catch short circuits by listening for that unique clicking sound that the breaker makes as you turn it on. If it’s absent, it’s 50/50 a short circuit problem or the breaker has gone out of commission.
  • As for ground faults, I’d trust the practiced eye of an experienced electrician more. I can’t stress this enough, particularly when you’re dealing with a problem in your conduit system. Do your best to have them checked and maintained consistently by electricians.
  • When diagnosing circuit overloads, you only need to unplug as many appliances as you deem necessary to ensure you’re within the right capacity. Once you reboot the circuit breaker after it has tripped, it should work fine. Otherwise, there may be some other issues.

Conclusion

Always look at the four possible reasons I outlined here if you want to know what causes a circuit breaker to go bad. Furthermore, remember that you’ll have to promptly replace the ones that fail without tripping. If you want to confirm your diagnosis, don’t have second thoughts about contacting a professional electrician.

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