5 Essential Steps: Installing a Subpanel in Your Home

Subpanel installation steps

Installing a subpanel is a great way to add more circuits and increase your home’s electrical capacity. It’s also a relatively simple DIY project that can save you money on an electrician. However, it’s important to note that working with electricity can be dangerous, so it’s important to take all necessary safety precautions. If you’re not comfortable working with electricity, it’s best to hire a qualified electrician to install your subpanel.

The first step in installing a subpanel is to choose a location. The subpanel should be located in an accessible area that’s protected from the elements. Once you’ve chosen a location, you’ll need to run electrical conduit from the main panel to the subpanel. Conduit is a pipe that protects electrical wires from damage. You’ll also need to install a circuit breaker in the main panel to protect the subpanel circuit.

Once the conduit is installed, you can begin installing the subpanel. Start by mounting the subpanel on the wall and then connecting the wires from the conduit to the subpanel. Be sure to follow the manufacturer’s instructions carefully. Once the subpanel is installed, you’ll need to turn on the circuit breaker in the main panel and test the subpanel to make sure it’s working properly.

Mounting the Subpanel

Before mounting the subpanel, you will need to gather your materials and tools. You will need a subpanel, mounting screws, a screwdriver, a wire stripper, and electrical tape. Once you have gathered your materials and tools, you can begin the mounting process.

1. Choose a location for the subpanel. The subpanel should be mounted in a dry, well-ventilated area. It should also be easily accessible for future maintenance.

2. Mark the location of the subpanel on the wall. Use a pencil to mark the location of the top and bottom of the subpanel.

3. Drill pilot holes for the mounting screws. Use a drill bit that is slightly smaller than the diameter of the mounting screws. Drill the pilot holes at the marks you made in step 2.

4. Mount the subpanel. Place the subpanel over the pilot holes and insert the mounting screws. Tighten the mounting screws until the subpanel is securely mounted.
a. If you are mounting the subpanel on drywall, you will need to use drywall anchors. Drywall anchors are small, plastic devices that are inserted into the drywall and provide a secure hold for the mounting screws.
b. If you are mounting the subpanel on a concrete wall, you will need to use concrete anchors. Concrete anchors are metal devices that are inserted into the concrete and provide a secure hold for the mounting screws.
c. If you are mounting the subpanel on a wood surface, you can use wood screws to secure it.

Surface Type	Anchor Type
Drywall	Drywall anchors
Concrete	Concrete anchors
Wood	Wood screws

5. Connect the electrical wires to the subpanel. Use a wire stripper to strip the insulation off the ends of the electrical wires. Connect the black wires to the black terminals on the subpanel. Connect the white wires to the white terminals on the subpanel. Connect the green or bare copper wire to the ground terminal on the subpanel.

6. Secure the electrical wires. Use electrical tape to secure the electrical wires. Wrap the electrical tape around the wires several times to ensure that they are secure.

7. Close the subpanel cover. Once you have connected the electrical wires, you can close the subpanel cover. Make sure that the cover is securely closed so that no one can accidentally come into contact with the electrical wires.

Connecting Feeder Cables

1. Turn off the main power supply.
Before beginning any electrical work, always turn off the main power supply to the area where you will be working. This will prevent any accidents from occurring.

2. Identify the feeder cables.
The feeder cables are the large cables that will connect the subpanel to the main electrical panel. They are typically black or red and are often bundled together.

3. Cut the feeder cables to length.
The feeder cables should be cut to length so that they can reach the subpanel without any excess. Be sure to leave enough slack so that the cables can be easily connected.

4. Strip the ends of the feeder cables.
The ends of the feeder cables must be stripped in order to make the connections. Use a wire stripper to remove about 1/2 inch of insulation from each end of the cable.

5. Connect the feeder cables to the subpanel.
The feeder cables are connected to the subpanel using circuit breakers. Each circuit breaker is rated for a specific amperage, so be sure to select the correct circuit breaker for the size of the feeder cables. To connect the feeder cables, simply insert the ends of the cables into the terminals on the circuit breaker and tighten the screws.

The following table shows the wire sizes and circuit breaker amperages that are typically used for subpanels:

Wire Size	Circuit Breaker Amperage
10 AWG	30
8 AWG	40
6 AWG	50
4 AWG	60
2 AWG	70
1 AWG	80
1/0 AWG	90
2/0 AWG	100
3/0 AWG	125
4/0 AWG	150

Installing Circuit Breakers

Once the subpanel is installed, it’s time to install the circuit breakers. Here’s a step-by-step guide:

1. Identify the Correct Circuit Breakers

Choose the appropriate circuit breakers for the circuits you’ll be connecting. Refer to the subpanel’s documentation for compatible breakers.

2. Gather Necessary Tools

You’ll need a screwdriver, a torque wrench, and any specialized tools mentioned in the circuit breaker’s instructions.

3. Install the Ground Bus

Connect the green ground wire from the subpanel to the ground bus in the subpanel using a torque wrench.

4. Install the Main Breaker

Insert the main breaker into the top slot of the subpanel and push it in until it clicks into place.

5. Install the Circuit Breakers

Insert each circuit breaker into its designated slot. Twist it clockwise to lock it in place.

6. Tighten the Terminals

Tighten the terminal screws on each circuit breaker using a torque wrench. Follow the manufacturer’s torque specifications to ensure proper connections.

Tip: Refer to the subpanel’s user manual for detailed instructions and safety precautions.

Circuit Breaker Type Amperage Range Usage Single Pole 15-20 amps Standard lighting, wall outlets, and appliances Double Pole 30-60 amps Air conditioners, ovens, water heaters Quad Pole 100-200 amps Heavy-duty appliances, electric vehicles

Wiring the Circuits to the Breakers

Once the breakers are installed, it’s time to wire the circuits to them. This is a relatively simple task, but it’s important to take your time and make sure that all the connections are secure. Here are the steps on how to do it:

1. Start by cutting the circuit wires to the appropriate length. They should be long enough to reach the breakers without being too long or too short.

2. Strip the insulation off the ends of the wires about 1/2 inch.

3. Bend the bare wires into a U-shape.

4. Push the U-shaped wires onto the terminals on the breakers.

5. Tighten the screws on the terminals to secure the wires.

6. Repeat these steps for all of the circuits.

7. Once all of the circuits are wired, double-check all of the connections to make sure that they’re secure.

8. Finally, turn on the main breaker to power up the subpanel and test all of the circuits to make sure that they’re working properly.

Circuit	Breaker Size	Wire Gauge
Lighting	15 amps	14 AWG
Outlets	20 amps	12 AWG
Appliances	30 amps	10 AWG

Finalizing the Installation

1. Install the Cover: Secure the subpanel's cover onto the enclosure using the provided screws. Ensure it's properly fastened and aligned.

2. Attach Conduit and Wire: Connect the conduit and wires from the main panel to the subpanel's corresponding terminals.

3. Tighten Terminals: Use a torque wrench to securely tighten all terminal screw connections. Ensure they meet the manufacturer's recommended torque specifications.

4. Test Polarity: Confirm the correct polarity using a voltage tester. Ensure the neutral and ground wires are connected properly.

5. Restore Power: Flip the main breaker in the main panel back on to energize the subpanel.

6. Inspect for Heat: Observe the subpanel for any excessive heat or loose connections using a thermal imaging camera or other suitable device.

7. Label and Document: Affix a label on the subpanel indicating its purpose, voltage, and amperage. Additionally, document the installation details for future reference.

Circuit Labeling and Identification:

8. Identify each circuit in the subpanel clearly using labels or tags. This facilitates easy troubleshooting and maintenance.

9. Create a circuit directory or install a directory holder on the subpanel's interior. This allows for quick identification of circuit locations.

10. Regularly inspect your subpanel to ensure it remains in good working order and address any potential issues promptly. Inspect terminal connections for tightness, check for any loose wires or damage, and ensure the cover is securely attached. By following these steps and maintaining your subpanel, you can enhance safety and reliability.

How To Install A Subpanel

Installing a subpanel is a great way to add more circuits to your home without having to upgrade your main electrical panel. A subpanel is a smaller electrical panel that is connected to your main panel and provides power to additional circuits. Installing a subpanel is a relatively simple process, but it is important to follow all of the instructions carefully to ensure that it is done safely and correctly.

To install a subpanel, you will need the following tools and materials:

A subpanel
Electrical wire
Conduit
A circuit breaker
A screwdriver
A wire cutter
A level

Once you have all of the necessary tools and materials, you can begin the installation process. The first step is to choose a location for the subpanel. The subpanel should be located in a dry, well-ventilated area that is easily accessible. Once you have chosen a location, you need to mount the subpanel to the wall. The subpanel should be mounted securely using screws or bolts.

The next step is to connect the electrical wire to the subpanel. The electrical wire should be sized according to the amperage of the circuit breaker that you will be using. The wire should be cut to the appropriate length and then stripped at the ends. The stripped ends of the wire should then be connected to the terminals on the subpanel. The connections should be made securely using a screwdriver.

Once the electrical wire has been connected to the subpanel, you can install the circuit breaker. The circuit breaker should be installed in the appropriate slot on the subpanel. The circuit breaker should be turned off before it is installed. Once the circuit breaker is installed, you can turn it on.

The final step is to connect the conduit to the subpanel. The conduit should be sized according to the number of wires that will be running through it. The conduit should be cut to the appropriate length and then attached to the subpanel using a conduit connector. The wires should then be pulled through the conduit and connected to the appropriate terminals on the subpanel.

Once the subpanel is installed, you should test it to make sure that it is working properly. To test the subpanel, turn on all of the circuit breakers. If the circuit breakers trip, then there is a problem with the installation. The problem should be corrected before the subpanel is used.