Installation of a circuit breaker is considered to be the most intimidating part of home electrical work.Most people don't do it themselves out of fear.Installation of circuit breakers into most residential electrical panels doesn't have to be complicated.You can install a circuit breaker in your home if you understand the layout of your electrical panel and take proper precautions.
Step 1: The power supply should be turned off.
Set the Main circuit breaker to the "Off" position by locating it in the panel.The top or bottom of the panel is where the circuit breaker will be located.If you don't see a circuit breaker labeled "service disconnection" or "main" in the panel, it is most likely in another panel or a gray box that houses the utilities meter for many houses and mobile homes.Until you find the main circuit breaker, look for other panels.If you suddenly lose power, turn off all computers in your home.
Step 2: The circuit breaker arrangement should be inspected for unused locations.
To find a blank area on the electrical panel that could hold a circuit breaker, look for spaces at the top and bottom of the cover.The panels themselves don't have provisions to mount a circuit breaker at these locations.If the unused location has a knockout plate over it, you will have to remove it before completing the installation process.Identifying a space where you can install the circuit breaker is all you need for now.
Step 3: The electrical panel cover has to be removed.
The screws supporting the cover need to be removed with a screwdriver.As you remove the last screw, use 1 arm to hold the panel cover in place.Remove the cover from the panel.If the panel cover slips and falls, the breaker handles could be damaged.A friend can help you hold the panel cover in place.
Step 4: Make sure the power is off when you test the panel.
A test light or meter can be used to check for power.Touch one probe to ground and the other to the screw terminal of a circuit breaker that has a black, red, or blue insulated wire.The panel will need to be turned off if 120 is indicated.Make sure the test light is set to the highest AC range you can find.The power on the terminals that have cables connected will always be indicated by the Service Disconnect or Main circuit breaker in this panel.When located in the panel, the Main or ServiceDisconnect connects to the bus bar.When the breaker is off, the bus bar should not have power.This "seemingly conflicting" information makes it impossible to recommend testing at the Service Disconnect or Main circuit breaker.It's not safe to put a circuit breaker in an electrical panel that still has power.If power is present on a circuit breaker other than the main one, do not continue.
Step 5: There is an unused space next to the circuit breakers.
The new circuit breaker needs to be placed next to the existing one.To make sure the location is in line with the unused location on the cover, compare it to the one that was removed earlier.The cover needs to have provisions for exposing the new circuit breaker if the knockout plate is removed.The circuit breaker will have to be in a different place if there is no plate to remove.
Step 6: Make sure you have the correct breaker.
There are approved types of circuit breakers that can be installed in the panel.It is a code violation to remove from the list.Only the circuit breakers that are allowed to be installed in the panel are used for maximum safety.Even if other brand breakers are labeled as "fits (brand name here) panels", the only breakers allowed to be installed are from the same manufacturer.The circuit conductor's rating should not be exceeded by the breaker.This is the amount of power needed for #14 copper, 20% for #12 copper and 30% for #10 copper conductors or wires.The code book can be used to determine sizes for other circuits.The terminal should be large enough to hold the wire.The need to remove strands of wire to fit the terminal is an indication of an error somewhere along the line.
Step 7: The circuit breaker handle should be turned off.
There are three possible positions for the circuit breaker.Before you install the breaker, make sure you push the handle towards the off position.
Step 8: The bars in the panel should be aligned with the circuit breaker.
The hold-on clip on the bottom of the breaker should be attached to the plastic grab bar in the panel.Once attached, pivot the circuit breaker on the mechanical contact and roll towards the center of the panel to make sure the bus bar is still aligned with the slot or opening.If you apply pressure to the breaker, it will become part of the plastic bar.
Step 9: Place the circuit breaker on the bus bar.
Use your thumb to press the circuit breaker until it snaps into place on the bus bar.The breaker is held in place by the panel cover and spring clips.It should not have to be forced to sit.
Step 10: The circuit wiring needs to be connected to the electrical panel.
To connect the white neutral wire and black hot wire to the breaker, you need to make sure the circuit breaker is on.Attach the wires to the appropriate terminal locations, then tighten the screw over the breaker's connection terminal.The neutral and hot wires should be marked on the circuit breaker label.Black and red hot wires are used to connect a double pole breaker.Make sure the switch you use is designed to be used as a double breaker.There is no need to bend the end of the wire into a hook, it just needs to be inserted into the terminal.
Step 11: The knockout plates should be removed from your cover.
If you bring the cover up to the panel, you can see the new circuit breaker location.To remove knockout plates from the cover location, use a pair of pliers.To remove the knockout plate, simply grip with the pliers and move the metal back and forth until it comes away.
Step 12: Remove all foreign objects from the panel.
A short circuit from the interior of the panel could be caused by tools, wire scraps, or other foreign objects.The cover should be placed on the panel to make sure that the circuit breaker is seated at both contact points.The cover needs to be re- screwed onto the panel.
Step 13: You can test your new circuit breaker by turning on the main breaker.
To restore power to the panel, stand on the side of it and set the ServiceDisconnect or Main to "On".The new circuit needs to be checked for correct operation.There is a test light or meter.Before attempting a reset, clear any short circuits.
Step 14: The circuit breaker needs to be labeled.
There is a circuit directory on the inside of the panel door.Write a description of the circuit in the space provided if you have a load type such as a refrigerator or living room.If circuits were moved to install the new circuit, be sure to change the directory.