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install a sub-panel like experienced electrician

What is a Subpanel: A Complete Guide to Subpanels

A subpanel is a smaller service panel that helps distribute energy to specific areas of the building or from home. A subpanel is a satellite breaker panel that extends the capacity of the main panel. A 240V double pole circuit breaker on the main service panel usually supplies power to the subpanel. The single feeder circuit is also divided into several branch circuits in the secondary panel.

The main panel is where power is distributed to the various branch circuits in your home.

At least every house contains a main service panel. But even the smaller panels called secondary panels are just as important. Subpanels allow you to add additional circuits for new fixtures, additions, or anywhere new circuits need to be run.

According to the National Electric Code (NEC), there is no limit to the number of subpanels a home can have, as long as the usage does not exceed the capacity of hall.

What is the difference between Main Panel and Sub Panel?

The main panel is the entry point for electricity from a utility company into your home. At the same time, a sub-panel acts as an intermediary between the circuits connected to your property and the main panel. They connect to the main panel via a power circuit.

The main panel regulates the electrical connection and controls the power that arrives at the outlet branches of your property. In most cases, the main panel is equipped with circuit breakers to regulate branch circuits and subpanels.

It has a main switch used to disconnect power entering the panel and any sub-panels that serve different areas of your home.

A subpanel can have multiple subpanels. Although a sub-panel works the same as the main panel, it cannot generate or add additional power independently. Indeed, they feed the main panel.

You need to install subpanels in your electrical system for several reasons:

Separate use: if you operate a restaurant, production workshop, healthcare facility, dental clinic, mall, school, or store, you may have various power consumption needs.

Security enhancement: While the main panel is placed inside the building, a secondary panel can be placed anywhere. It can be useful, especially during emergencies or fires when entering the house to turn off the main service panel is dangerous.

Add circuit space: The main service panel has a maximum number of switches and circuit breakers it can hold. You should choose a secondary panel if you want to create more space on your circuits.

Do you need a subpanel?

Are you considering adding a new electrical sub-panel because your main panel no longer has space for switches? Wait, you might not need a new subpanel.

If your main circuit breaker allows tandem switches, you can increase your home's panel capacity by replacing existing single-pole switches with tandem switches. Tandem switches allow two branch circuits to share circuit breaker space.

New circuit breakers can handle additional branch circuits without the need to upgrade the electrical panel or create a new sub-panel. .

Can a panel be a secondary panel?

You can use a panel as a secondary panel but under certain conditions. A standard load center can be used as a sub-panel in the building. However, in this case, it is necessary to remove a neutral connection jumper.

In a subpanel, a neutral is completely isolated from ground.

When you decide to do electrical work, you must turn off the power completely.

You can only connect ground and neutral at one point on the main panel for residential service. You will have a machine screw or metal strap that connects the neutral bus bar to ground or the panel box of most panels.

Next you need to remove the screw or metal strap. It is therefore possible to use a panel as a sub-panel as long as the correct connections are made.

Are subpanels safe?

It is very safe to work with a subpanel. One of the reasons you should use a subpanel is to provide building and circuit security.

For example, if you want to manage repairs and maintenance of your circuit, you can disable the subpanel to prevent current flow. . If power to the subpanel is interrupted, the risk of electric shock is reduced.

How does a secondary panel work?

For a secondary panel to operate, two hot wires are required connected to a 240V double pole switch in your main panel. It also requires a ground wire and a neutral wire.

The cable used in this section is a grounded three-wire cable. The hot wires are called power supplies and provide power to your subpanel.

The cables connect to the 240 V main switch in the sub-panel, connecting the shutdown via the hot busbars. Each circuit breaker connects to the busbars to distribute power to branch circuits passing through the subpanel.

Does a sub-panel need the main switch?

It is not necessary to have the main switch on a sub-panel in your building. However, it is not limited; you can include it if you see fit.

If you want to include a main switch in the sub-panel, you need to remove the lugs where the black and red wires were connected and screw or screw the switch in that exact position. It is then possible to connect the black and red wire to the cable lugs above the switch.

How many subpanels can you have?

You may install any subpanels for the main 200 amp panel as long as the combined demand does not exceed 160 amps.

How far can a subpanel be from the main panel?

You can place a secondary panel anywhere in the house, regardless of the location of the primary panel. However, it is recommended to mount it at least one foot from the main panel. There are also cases where a sub-panel is placed outside the house while the panel is inside.

However, the most important thing to focus on is the installation process and cable selection. You must securely fasten the subpanel to a stable surface or wall with fasteners.

If you are installing the subpanel outdoors, you must choose an approved outdoor enclosure. Depending on ground voltage, always leave at least 3 to 4 feet of clearance around the sides of the panel.

You should also make sure that the panel is easily accessible. Therefore, it would be better not to install it much above the ground. The right feet would be in 4.

5 to 5 feet

Cable from main panel to sub-panel is amperage dependent. For example, for a 30 A panel, use a 10 AWG three-wire conductor.

If you have a 60A panel, use 6 AWG wire. For a 100 A panel, 2 AWG aluminum wire or 4 AWG copper wire would be appropriate.

A three-conductor cable contains four wires inside.

Where do you place a subpanel?

You can place your subpanel anywhere. You can put it inside or outside the house or building. However, the best place to place it is about one meter from the main service panel.

Having the secondary panel outside the building is a safety measure in case of an emergency. For example, in the event of a fire, you can easily change the power supply without moving around the house.

It would be helpful to mount the sub-panel on a stable surface or wall to prevent damage from external force such as wind.

Instead of worrying about the location of the subpanel, it is better to focus on implementing a perfect installation process.

How to install a secondary panel

It would be better to turn off the main panel when installing.

The installation process is simple and takes about 2 hours.

Tools needed

A hammer

A screwdriver

A flashlight

Voltage tester

Long nose pliers

Lineman pliers

Wire strippers

Hardware Needed

Mounting Screws


Approved Power Cord

Approved power switch

Staples or cable ties

A switch for your new circuits

If you don't have the skills to carry out an installation, it is better to call on an experienced professional. Follow the steps below to effectively install a subpanel.

Mount the subpanel

This is the first step to implement when installing the subpanel. It would help to mount the sub-panel about a foot from the main panel.

hunger apple, [10/30/2022 8:24 PM]

I would help if you deliberately decided how your cables would move and pulled the cables accordingly. You also need to add cables and strip the wire sheath.

This is also a great time to remove a knockout and run the wires through. It would be better if you fixed the cables as well.

Plan the route

At your main service panel, plan the route of the cables: neutral wire, ground wire, black hot wire and red hot wire.

Start by removing the jacket and then removing the knockout ball. You can then lock the cable.

Finally, carefully route the earth and neutral cables and connect them to the busbar.

Strip the wires

Cut, route and strip the black and red wires. You can then plug them into your power switch.

Flip the switch to the correct position.

Connect the cables

The path has been cut and strip the power cables in the subpanel. You can then proceed to connect them to the terminals.

Connect the red and black wires to the hot busbars. The neutral wire must be connected to the neutral terminal, while the earth wires must be connected to the earth busbar.

Run the wire for your new circuits through the subpanel, then secure those wires. Connect the white wire to the neutral busbar, the hot wire to the circuit breaker, and route the wires around the perimeter of each circuit.

Should you inspect or replace your subpanel?

A proper inspection by a knowledgeable professional can make all the difference if you have a subpanel in your building or home. An expert can also advise you whether to replace it or not.

There can be several issues with the secondary panel, including poor bonding, corrosion, and missing clamps. Another common problem could be incorrect wiring.

Identifying an improper wiring problem can be more complicated than you think for most business owners or homeowners. If you don't identify these problems well, they could cause more devastating, costly, and larger problems in the future.

Always hire a professional inspector or local technician to give you a clear overview of the problems before you escalate further.

If your subpanel has problems, you should replace it immediately. A longer wait may result in danger and injury to building occupants.

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