Circuit breakers are one of the most important parts of electrical circuits as they serve as safety features that prevent accidents. If there is an overload of power or a short, it would cut the flow of electricity, eliminating the possibility of further damage or potential accidents. This is why it is vital to regularly check if your circuit breakers are still functioning properly so that you can change them if needed. You can change damaged or faulty circuit breakers with new or used breakers. You can also do the installation process on your own, provided that you understand how circuit breakers and electrical systems work.

Before replacing your old breakers with used breakers, it is important to do some troubleshooting first to determine if the circuit breakers are indeed causing the problem. Here is a guide on how to do it.

First, you need to turn off the main breaker in the electrical panel of your home. In larger homes, there may also be sub panels, particularly in two-story homes so make sure that you have been able to shut off the main breaker (usually 100 to 200 amps) of the whole house. If you have more technical know-how, you can look for the breaker inside the main panel that controls the particular sub panel that you are working in and then shut this breaker off. Doing this would keep the rest of your home with power while working in the sub panel. If you are unsure on which breaker controls the sub panel that you are working in, just shut off the main breaker.

The next step would be to access the breakers. To do this, you would need to remove the breaker cover inside the panel or sub panel. After opening the door of the electric panel, you would see that the breaker cover is attached with a screw at the bottom portion of the panel. Unscrew this and set it aside. The cover should move toward you as you remove the screw. Also make sure to gently lift it up and pull it out and down. You would now have access to the circuit breakers. Keep in mind that the current is still live going to the main breaker so do not put touch the area that is above the main breaker using your bare hands or metal tools as you work in the panel. Additionally, if you are in a sub panel which has the main breaker inside, you should also follow this safety rule.

After shutting off the main breaker, you can then test the circuit breaker that you suspect to be faulty using an ammeter or a test meter. You should see two test leads. Position one of the leads on the metal screw that is in the breaker and the other lead on the neutral bar which is inside the panel. The white wires should all be terminated in the neutral bar. You should not be reading any voltage on the ammeter. If the suspected problem breaker is of a 220 volt size, it should have a bar (there are some which have double width and some with single switch) that connects two 110 breakers. Testing this kind of breaker is done by positioning both test leads on the breaker, one to each of the metal screws on the bottom of the breaker. As an added safety precaution, be sure to test each metal screw on to the neutral bar. You should not be getting any voltage readings in both tests. If you do, stop working and call in a licensed electrician. If you do not, you can proceed to the next step.

You have now determined that the problem breaker can be safely removed. The circuit breaker is usually mounted horizontally with the hot lead terminated under a metal screw. This would normally be a red or black wire in residential wiring and can be found to the left of the horizontal breaker. Using a flat blade screwdriver, turn the screw counter-clockwise just enough so you can release the wire. Move it away, towards the outer edge of your panel.