Circuit breaker plays an important role in the safety of our daily life because, it protects electrical equipment and devices against short circuit and overload faults.
The normal life of a standard circuit breaker is up to forty years. However, sometimes faults occur and a breaker goes bad.
In this article, I will discuss reasons, signs, and testing methods of bad circuit breakers.
What does a bad breaker mean?
Bad circuit breaker means a condition of the circuit breaker that has stopped working, tripping, having a burning smell, hot to touch, and or has physical damage.
When circuit breaker goes bad it can’t do its protection task as required! It becomes no longer suitable for reset and use.
It’s worth mentioning that the bad circuit breaker is not the same as the tripped breaker. You can reset a tripped breaker, while bad one should be replaced.
Can a circuit breaker wear out?
Yup, circuit breakers do wear out over time and because of faults like short circuits, and need to be replaced.
Not every tripped circuit breaker is a bad one, An authorized technician can judge each case and see if the breaker is bad.
I’ve written a detailed article about circuit breaker tripping, you can read it here for more information.
Usually the question ” Is my CB bad?” rises in the following cases:
- When the CB Keeps tripping
The circuit breaker should act and trip in case of a fault condition! The first thing to check is the circuit and the loads which are connected to the CB, not to blame the circuit breaker!
- CB is on the “on” position, but there’s no power to your outlets
If the circuit breaker is on the ON position and no power on the outlets this is not necessarily a bad breaker.
Any part of the circuit may be the reason of no power situation. A cut wire, a bad outlet or even a bad appliance may be the reason.
It is possible that if you’ve a bad circuit breaker and replaced it without clearing the fault in the circuit, the new one also can become faulty, so it is recommended that you first troubleshot and clear the fault and then replace the bad breaker.
Should I replace A tripped circuit breaker?
No, you don’t have to replace the circuit breaker whenever it trips, you have to determine the cause of why the circuit breaker is tipped, fix it and reset the circuit breaker.
Whenever a breaker trips, you tend to blame the circuit breaker immediately. In most cases, the circuit breaker is doing its job and protecting your home from a fault or overload in the circuit somewhere within the house as a result of the circuit breaker tripping.
When you clear the fault and switch on the circuit breaker, it should work normally as a good circuit breaker, but if after clearing the fault, it trips again and again, it’s a bad circuit breaker and you need to replace it.
My circuit breaker stuck in the middle! What does it mean?
When a breaker is in the middle position, it has tripped due to an overcurrent issue, this overcurrent may be a short circuit, a bad device or an overload.
This implies that too much power was running through the circuit that the breaker is supposed to protect, and as a result, it responded by shutting off to prevent overheating the wires and a potential fire.
Usually, a tripped breaker isn’t a bad one, as I just told you above in this article, it’s just doing what he should do, protecting you.
There may be a “short” in the circuit or too many appliances consuming more amperage than the breaker can handle (usually 15 or 20 amps for general purpose circuits).
A short occurs when an electrical current is redirected to a path with little resistance to current flow, such as through frayed or loose wires or contact with parts of an item that shouldn’t be electrified.
An overcurrent occurs when you connect too much load to the same circuit.
For more about short circuit, read my detailed article here.
How can I tell if a breaker is bad without a multi-meter?
When a circuit breaker goes bad, it trips regularly, has a smoke on its body, has a clear melted terminal or when you check its voltage with AVO-meter while it is in the ON position you will find no output power.
Another way is to isolate the CB input terminals, and use the multi-meter as a buzzer to verify the continuity of each phase in both On and Off positions, I don’t have to till you that in the off position it should not buzz. If it’s bad, it most likely will buzz in the Off.
I can’t count the number of bad circuit breakers I have seen during my work as electrical maintenance engineer.
The first sign of a bad circuit breaker I notice is smoke on its body.
Then, comes melted breaker body. I don’t even have to use a multi-meter to check a bad breaker with these clear damage signs.
I don’t even try to fix it. Replacing bad CB is the only direct solution.
Keep in mined that CB is a protection device to protect against short circuit and over current.
In normal conditions the CB connects power from source to the load side. In fault conditions the CB must trip immediately.
Fault conditions like short circuited appliance, cord or overloaded circuits. The point is not every tripping condition is a sign of a bad CB.
To know if the CB is bad or the circuit has a fault, I isolate the wiring from the output side of the breaker and then connect it to the ON position, If it trips then it’s a bad one.
Hint: If a CB tripped due to large amount of current i.e short circuit or overload, it will be hot, and will not accept the ON position until its temperature decrease. Don’t reset it immediately.
Signs of bad breakers you can recognize without a multimeter!
Yep, you can tell if a circuit breaker is bad without a multimeter. To mention a few, the breaker doesn’t stay in the “reset” state, the electrical panel box smells like burning, the breaker is hot to touch, there is a physical damage, it trips a lot or it’s just plain old.
When a circuit breaker in your house stops working, it starts to show specific obvious symptoms that alert you to the fact that it hasn’t been operating at its best.
Many signs can tell you if a circuit breaker is bad. I will list them, then let’s discuss each of them.
- Circuit breaker keeps tripping.
- Circuit breaker doesn’t stay ON.
- Burning smell.
- Very hot to touch.
- Circuit breaker body melted areas.
Now, let’s discuss some of these signs in details.
If a circuit breaker is tripping frequently, This may be a sign of a bad circuit breaker.
But, before we say that the breaker needs repair or replace, we should check the appliances and wiring that are connected through this breaker for any damage, short circuit or overloading.
This check is essential before replacing the circuit breaker. In many cases the circuit breaker is tripping to protect the electrical load against a short circuit or an over load while it is not bad. You may need to contact an authorized electrician for this task.
I have written a detailed article about ,What Causes A Circuit Breaker To Trip? , I highly recommend reading it for more information.
Breaker doesn’t stay in the ON position
A circuit breaker has two positions, On and Off. In normal condition, it is in On state. If any short circuit occurs, the breaker goes into the off state. When you put it back into on state it does not rest at the position and trip again.
So, this may be a sign of a bad circuit breaker. But as I’ve mentioned above, If the load side has an issue then the breaker is just doing its job.
In this case we isolate the load wiring from the CB and reconnect the CB to ON position, If the breaker tripped again, It is bad CB.
Burning Smell and Hot to touch
Another sign of a bad CB is, if you smell a burning smell from the CB panel. It is confirming that the circuit breaker is no more good, keep in mind that any other device in the panel may be the source of the smoke smell, like relays, wires or switches.
Similarly, if you touch a breaker and it is too hot, means it is warmer than normal condition. It means that the CB may blown out.
We suggest cutting off the main power line and contact a professional electrician.
Melting or visually damaged areas
Are any scorch marks around the circuit breaker, outlets, or appliances? If so, turn off the house’s electricity and take necessary measures to fix it or call an electrician.
The home can soon catch fire as a result of a melted wire if not fix it ASAP.
What causes a circuit breaker to go bad?
There are three main reasons for a bad CB. It is either due to:
- A short circuit. A short circuit occurs when electric wires accidentally touch the ground.
- Overloading, When the amount of current flowing in the circuit increase from the rated current limit of the CB. I have written a detailed article about OverCurrent you can check it out for more information.
- Loosen connected wiring can easily cause the terminal of the CB to overheated and then melted.
Is a bad breaker dangerous?
Yes, it is dangerous, We are talking about possible electric shock, fire danger and loss of overcurrent protection. When the CB is bad it will not do its protection job.
In some cases loosen connection increases the resistance and so increases the current, the higher the current the higher the heat it produces, overheating may cause plastic parts of the CB body or the wires insulation to melt and may cause a fire.
Other form of the hidden hazard in a bad Cb is that it may pass power even it is in the OFF position.
If you are working, and you isolate the bad CB, it could cause electric shock because it’s not really isolating power. This is why we double check power isolation with AVO-meter or voltage tester.
Bad circuit breakers are dangerous most when you rely on them as a protection device, while the fact is that they are out of service after going bad.
Can you fix a bad circuit breaker and reuse it?
Bad breakers can’t be fixed. In most cases, resetting the breaker will restore power as long as the load has been minimized and the load has not been exceeded to a certain value. A bad circuit breaker needs to be replaced.
Circuit breakers are designed to handle a certain current value in normal operation and a short circuit current value in fault conditions.
If the current exceeds the rated value of the circuit breaker, then the breaker will trip without being damaged.
If the circuit breaker trips due to a short circuit current lower than the circuit breaker short circuit current the breaker will trip without being damaged.
On the other hand, it will get damaged if the short circuit current exceeds the designed short circuit current of the breaker.
Can I change a bad breaker myself?
Yup, you can change a bad breaker with the right tools and a little electrical knowledge and safety precautions.
Circuit breakers often don’t need to be changed as opposed to a fuse, which may be reset. A circuit breaker may occasionally malfunction or fail, necessitating the installation of a replacement breaker.
I highly recommend replacing it under a supervision of an authorized electrician for the first time to get some safety precautions. If you need to replace your circuit breaker yourself without the help of an electrician, the tips listed below must be followed in order to replace the circuit breaker
- Buy a new CB. Make sure it matches the specifications.
- Shut off all of the branch circuit breakers, then the main circuit breaker in order to replace a typical residential circuit breaker. (Power isolation is the first safety step in this job)
- Double check power isolation with a voltage tester or AVO-meter.
- Wear isolating gloves and safety glasses. Read my article “What electricians should and shouldn’t wear?” for more information, its on my other Site “Safety Frenzy”.
- Simply removing the panel cover will allow you to replace the circuit breaker.
- After removing the cover, you may pull the wire away from the defective breaker and disconnect it. Now, gently pull the broken circuit breaker out of place. To properly install the new circuit breaker, pay attention to how the old one locks into place in the panel. Usually, postures that are upside down or twisted about don’t work. Insert the replacement circuit breaker after that.
- While the circuit panel is open, inspect the other branch circuits to ensure they are installed correctly and secure any loose components.
- Reinstall the panel cover and confirm that each branch circuit switch is set to the “off” position. Continue to switch the branch circuit breakers once after turning on the main circuit breaker. Test the circuits to ensure that they are stable and functioning correctly.
You’re done if the replacement circuit functions properly. If the circuit issue persists, you might wish to inspect the electrical equipment connected to the circuit or get further advice from a specialist.
How long does it take to replace a breaker?
Normally In the best-case scenario, it takes 30 minutes to replace a breaker.
Sometimes the breaker is in the center of a series of incorrectly fitted breakers or doesn’t fit well on the clips. You may need more than 30 minutes to clean up the mess in this scenario.
Take into consideration replacing a circuit breaker may take much less than 30 minutes if an expert electrician is doing the job.
If the circuit breaker in a tight place you may take more time to replace it. In my work as an electrical maintenance engineer, it may takes a lot of time to replace one circuit breaker. But this is not the normal case.
In your home, you should take the time you need, for your own safety.
For me, in my home I take my time also when doing any electrical task. The reason is my children are around me, and I have to keep an eye on them to keep them away while working with electricity.
That’s why I never care about time, instead I care about safety.
Can a breaker go bad and still work?
If a breaker goes bad, it cannot work as expected, however in rare cases a bad circuit breaker keeps passing electricity to the load, even if it’s on the OFF position.
Further more, a bad circuit breaker still work, i.e delivering electricity to the load as normal, but it doesn’t expected to protect the circuit.
Most common case is after going into bad condition, CB stops passing supply, and you loss power to a circuit. Replacing the circuit breaker in this case is the only choice.
But, as I mentioned, you should check the circuit, wiring and loads first for any possible faults. If the circuit has a fault, repair it and check the circuit breaker for normal operation.
Some times we find a bad 3 phase circuit breaker on the OFF position with one phase only passing electricity. This is a tricky dangerous situation.
That’s why I never rely on switching a circuit breaker OFF to isolate power before doing maintenance work. Instead, I double check power isolation using a Multi-meter.
For more information about How to safely perform Electrical Isolation, read my article here.
Can a bad circuit breaker cause a low voltage?
Yep, low voltage might be caused by a faulty breaker. Although it is uncommon, but it’s feasible.
Voltage drop can happen if the breaker has a loose connection to the panel box. Loose connections increase the resistance and of course decrease voltage due to increased current.
One of the tasks we do during panels preventive maintenance is re tighten the connections. We do the same task for overhead power lines connections as well, We hire a third party company to do this task without power isolation.
My lights are flickering, Is it the circuit breaker?
Flickering or dim lights may be caused by a bad circuit breaker or a loose electrical panel connection.
Flickering lights indicate a poor connection, and the clamp connector where the breaker snaps into the panel is a specific problem area. This issue is more likely to occur with some models than others.
To resolve the issue, you have to tighten all loose connections first and check whether this flickering issue is resolved or not. If not, then you have to change the bad circuit breaker.
Can a bad breaker cause the neutral to get hot?
No, a bad breaker cannot be the cause of a hot neutral. So, the question is, should the neutral wire be hot? The answer is no. Through the neutral wire, electricity does not move. It’s safe, as opposed to the hot wire through which the electricity runs. However, why would a neutral wire be warm?
Here are three explanations:
- Inadequate connections are the main cause of a hot, neutral wire. This indicates that the circuit’s hotline is somewhere in the circuit or that the hot wire is damaged.
- High voltage is another cause of the neutral wire’s heating.
- Lightning strikes are a common reason why neutral wires heat up. Large quantities of electricity are generated whenever a lightning strike occurs on a power line.
Can a power surge damage my circuit breaker?
Power surge means an unexpected overvoltage, it’s can cause severe damage to a circuit breaker. In the worst-case scenario, it may fry a circuit breaker and also cause damage to other outlets in the same house.
A surge of power can cause damage to plugged-in appliances and equipment as well.
A circuit breaker is designed for a rated operating voltage. If the voltage increased too much, like in a surge, the breaker will go bad.
Similar to the surge effect, If you connect the circuit breaker to a circuit with higher voltage than its rated. The higher the voltage the more damage it causes t the breaker.
You can use a surge protection device to protect the circuit breaker. This device is used to protect against transient overvoltage or what is commonly known as a power surge.
Short circuit causes a breaker to go bad
A short circuit is a common cause of circuit breaker trips and damage. They are also more dangerous. Any circuit breaker is designed with two currents, rated current and short circuit current.
If the current of the short circuit fault is much higher than the designed short circuit current of the circuit breaker, the breaker will go bad.
If the short circuit current is lower than the designed value of the circuit breaker, the breaker would trip safely. And you can reset it.
A short circuit can happen if a fault occurs in your electrical outlets and a live or neutral wire comes into contact with it. This can also occur if the wiring of an appliance, plug, or other device is damaged.
If You have no power, while breaker doesn’t trip, what does it mean?
The Breaker may not be tripped, but the power may be off. No matter the circumstance, here are the reasons and suggestions to fix the issue if Breaker doesn’t trip but has no power.
- Power outage may be the first reason you should check. Make sure the main electrical panel has power.
- Wiring issue, wires are the connecting path from the breaker to the outlets, measure the breaker input and output power, if there is power then the wiring and the outlet itself may be the things to check.
- Main circuit breaker, some panels have one main circuit breaker feeding all of its components, i.e CBs, if the main CB is tripped then all other breakers will have no power without tripping.
- GFIs are small circuit breakers that didn’t trip but cut off power if they detect a fault. You should check if the GFCI button has to be reset.
- If your electrical distribution box has fuses as well as circuit breakers blown fuse. Search the fuse for a broken filament or burned glass and replace it with one of the same kind and amperage.
- Faulty circuit breaker. Change out the breaker. If you’ve determined that none of the aforementioned causes of the power outage are to blame, the problem is most likely that your breaker is bad. Use a multimeter to check its continuity for, but make sure it has no power before continuity test.
Can a power outage damage a circuit breaker?
A power outage cannot be the reason for any damage to the circuit breaker because a power outage means no power.
Furthermore, if you have a power outage, after restoring power, your CB doesn’t work properly. Is the outage the reason?
The answer is straightforward no, there is a possibility of any other fault in your house wiring or fault in the main cable that comes from your energy meter to your electrical distribution box.
One more cause to discuss here. A power outage may happen simultaneously with internal damage or a short circuit.
Then, when the power returns, your circuit breaker is damaged due to the short circuit, not the outage.
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