30 January, 2024

When we switch on the light or plug into an electrical outlet, we expect the power to turn on so we can go about our day. We only give it a little thought if something goes wrong!

Have you ever wondered what the standard electrical service for residential properties is? Your utility company has a total available capacity, measured in amps or amperes. The average home has between 100 and 200 amp residential service.

It’s essential to know the size of your house’s electrical service to see if it needs to be updated or if it can handle upgrades to your home.

What is the Standard Residential Electrical Service?

The first thing you need to understand is that the capacity of an electric service is measured in amperage or currents, not in volts. The higher the current capacity, the greater the electrical current will be available. 

What is the standard home electrical service for residential buildings? Current enters the building in two forms, 120 volts and 240 volts. The circuit is the amount of current that is flowing through the wires. 

The voltage is the amount of energy that is being carried. 

120 volts is used for small appliances, lights, and outlets. 220 volts are used for larger appliances such as air conditioning and electric ranges. 

Most modern homes have 220-volt electric service capacity. Older homes may need to be upgraded. 

To quickly check your voltage, look at the service entry cable. There are 3 wires: two “hot legs” and the neutral. The neutral wire will appear bare. The hot legs will have a black rubber covering. 

The 3 wires are connected to the service “riser” that runs down the wall of your home. Each hot leg carries 120 volts, delivering 240 volts. 

If these hot wires aren’t connected, it indicates you may need to upgrade.

What is the Capacity of a House’s Electric Service?

  • 60 Ampere is typically the lowest capacity for a 120/240 volt service
  • 100 Ampere is the standard amperage for a home that uses gas or hot water heating systems
  • 125 Ampere is quite rare 
  • 150 has become the typical minimum for modern homes. The standard house amperage
  • 200 Amperes is being installed in most new construction homes ansSmarthomes

3 factors determine the capacity:

  1. The capacity of the service entry cable (feeding your home) home electrical service
  2. The capacity of the main electric panel 
  3. The capacity of the main disconnect

In most cases, the 3 factors are the same. Understanding your home capacity is an important safety feature. Fire and other electrical safety concerns may arise due to aging, improper installation, or overloading of the system.

In instances when the 3 factors aren’t equal, the service cable would be a limiting factor and an unsafe condition.

How Should I Know What Size Electrical Service I Need?

There are 6 simple steps to determine which size electrical service you’ll need:

  1. Measure the diameter of the conduit that houses the service entry cable. 1-inch cable housing 6 gauge wire supplying 60 amp service. 1 ¼ -inch conduit can house 4 gauge wire, supplying 100 amp service. 2-inch is capable of supplying over 100 amp service
  2. Inspect the main service cable. 60 ampere are between ¾ inch and ⅞ inch wide. 100 ampere cables are 1 inch wide. 150 cables are 1 ¼ inches wide. 200 ampere are 1 ½ inch wide
  3. Look for the amperage rating listed on the label of your power meter
  4. Look for a label on your electric panel
  5. Check your panel for the main disconnect. It will be labeled as main and will indicate the capacity as 100A, 150A, OR 200A
  6. Compare the information and find the lowest value; this will help you find your home’s electrical service size.

ESD LLC is one of the leading providers in the Northwest for your circuit breaker and electrical equipment needs. Contact us for assistance, as we are a trustworthy company that provides great pricing and excellent service.

Let ESD LLC Assist You 

If finding out the standard electrical service for residential homes sounds more complicated than you expected, please call us so we can assist you. 

We have over 10 years of experience in the electrical field, and our experts are there to answer any of your questions. 

If your home system needs to be upgraded, have no fear; we offer the highest quality products. 

So please don’t delay. Give us a call today.