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400 Amp Residential Service – Do You Need It?

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You may be considering installing a new electrical panel. Although you may not be sure of how many amps your current service uses, you definitely know that your home is using more energy and that a larger service is going to be required..

What exactly is a 400 amp residential service?

400 amp residential service is when up to 96,000 watts are distributed through the service panel. It is needed for homes that are larger in square footage. If you use a lot of heating and air conditioning or you have added appliances and a swimming pool, then you may want to consider upgrading to 400 amps.

Abstract image of electrical boxes and conduit on the side of the building

While there are many electrical issues that are easy to fix, there are certain issues you should seek professional help with.

In this article, we will talk about amperage residential services, how to determine if you need to upgrade, and the cost of each system.

On top of this, we will discuss how to troubleshoot when your breaker is being overloaded. 

What Is 400 Amp Residential Service?

The amp service that is in your space pertains to your electricity and electrical panels. If you have a 400 amp service, that means you have 96,000 watts of potential electricity coming available at your home.

Meaning that this is the amount of electricity you are able to create before tripping the main breaker or fuse. If you overload your breaker or fuse you may have a variety of outcomes, none of them are good. 

This could cause your electricity to go out or falter. You may hear noises coming from your box or completely blow your fuse or breaker.

If any of these things happen to you, this could mean it’s time for an upgrade, or that you just need to cut back on the number of appliances you are running at one time.

How Do You Know If You Need 400 Amp vs. 200 Amp Or 300 Amp?

Depending on what you are looking to power, you may need one size electrical service over another.

For example, compared to older homes wired more than 30 years ago with 60 to 100 amps of service, newer homes generally run between 150 and 200 amps minimum (source).

Houses that are significantly larger can have up to a 400 amp service. 

outdoor cabinet for electrical equipment

The change in electrical service size has changed over time due to the increase in appliances being found in homes.

Therefore, before adding another appliance to your home it is important to consider if you have the electrical capacity to support the appliance. If you have large appliances such as:

  • Central air conditioning
  • Electric Dryer 
  • Dishwasher 
  • Hot tub 
  • Electric water heater 
  • Electric oven
  • Dishwasher 
  • Pool

Then you may be close to maxing out your amps available! Some signs it is time to upgrade to the next level include:

  • Hearing hissing from the box
  • Constant tripping of your circuit breaker 
  • If you still have an old-fashioned fuse box instead of a breaker box for your home
  • Flickering lights 
  • Buzzing 
  • Crackling sounds 
  • Blown fuses 

However, before you consider upgrading your system, remember that you should always consult an electrician and get written estimates.

By consulting a professional, and looking at how many high electricity appliances you have in your home, you will be able to make an informed decision about when you need to increase your electrical panel size at your home. 

What Wire Size Do You Need For a 400 Amp Residential Service?

Depending on your area and the existing power panel that you are upgrading, upgraded wiring between the power pole and new service will be required.

outdoor cabinet for electrical equipment

Often this upgrade service is provided at no cost to you, the homeowner, and is considered part of your ongoing electrical service billing.

As part of the permitting process your electrical contractor will likely need to meet with a representative from your electrical utility to approve the panel location (sometimes even if you are simply leaving it in the same place!) and to check the existing wiring condition and size from the pole.

In order to operate a 400 amp electrical panel at your home, you will need a 400 AWG (American Wire Gauge) wire between the pole and the new service. This equates to 355 copper amps and 270 aluminum amps.

For a full chart of wire size by amp rating, visit this website.

What Is The Cost To Upgrade To a 400 Amp Service?

The cost to upgrade to just a 400 amp panel will set you back between $2000 to $4000. Things to consider in the cost of your upgrade include:

  • Replacing your current panel box with a larger one 
  • Hiring a licensed electrician. An average upgrade will take about 8 to 10 hours of work. Most professionals will charge between $50 and $80 per hour—therefore you can expect to pay between $500 and $800 simply for project labor. Of course rates differ depending on the part of the country you are in and market demand. Be sure to get multiple quotes and ask for referrals from friends.
  • Permits – city or county permits will almost definitely be required before any work can begin. Typically your contractor will handle all of that for you, but those costs will be passed on to you as the homeowner in addition to the overhead they tack onto their time for handling it.

Keep in mind that your pricing can fluctuate a great deal depending on the condition of your site. Contingent on the condition, your electrician may need to put in more hours of work or take in more parts in order to upgrade your service.

The more parts your electrician has to buy, the more the project will cost you. 

If you are living in an old home and have a fuse box, this will need to transition to a circuit breaker box.

Professional electrician inspecting wires in electrical box

The cost to make this switch will range from about $1500 to $2000. This is an additional cost to consider along with your panel upgrade. 

If you need to move your electrical panel from one location of your site to another, you are looking at an additional cost of $1000 to $2000. Factors that may influence your need to move your box include:

  • Whether it is indoors or outdoors 
  • The size of your home (including how many floors are in your home)
  • The number of circuits you are looking to move
  • Whether or not the existing power wire runs over your house to the panel location. Most municipalities, especially those in high fire danger areas, will require a new location that does not have the wire going over the house at any point.
  • If your home and panel are up to code. If your current panel is not up to code, you may need to move the panel on top of getting a brand new panel!

With these additional factors, the cost of this project can start to add up. These are all factors to consider when looking to upgrade your electrical panel.

For additional information about the cost of upgrading as well as any additional costs that can come along with this project, check out this website.

Final Thoughts

If you are experiencing electrical issues within your work or home, walk through the steps above to determine what might be going wrong.

Troubleshooting what could be the root of the issue is important, but so is seeking professional advice and assistance when needed. 

Keep in mind that working with electricity can be dangerous and can cost you a lot of money if done incorrectly.

If you are looking to upgrade your amperage, move your electrical panel, or switch from a fuse box to a breaker box, do not attempt to do this on your own if you do not have the experience and tools needed. 

professional electrician examines cable connection in the electrical line

Injuries from electrical shock can be very serious and often life-threatening. When seeking professional advice, we recommend obtaining an estimate from three electricians.

This not only ensures you are getting the best price but also guarantees that you will find the root of the problem and avoid any unnecessary expenses. 

Finally, pay attention to how much you are loading up your electricity. If you live in an older house where your amperage may be low, stay cognitive of this.

Before buying a higher power dryer or hot tub, be sure your panel can hold that kind of electricity, and if it cannot, upgrade! 

If you are living in a newer house, be sure you know what your amperage is when you move in. This way you will have an idea of how much you can load up on electricity without blowing your breaker.

By having this information in the back of your mind, you can avoid future frustration and expenses due to electrical troubleshooting!


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