Understanding Your Home Electrical System

Understand Your Home Electrical System

Even if you're not a handyman, it's important to understand the inner workings of your home electrical system.

Maybe your power goes out unexpectedly, and you need to explain to an electrician what you suspect is going wrong. Maybe the power goes out in the middle of an emergency, and you can't get in touch with that electrician. Or maybe you're simply trying to understand what backup power source is right for your home.

These are just a few of many good reasons to have a basic knowledge of your home's electrical system.

In this post we'll help you gain that knowledge.

Let's start with a few important terms.

Learning home electrical terms

To gain a baseline knowledge of your home electrical system, let's learn a little vocabulary. These terms are essential, but are often confused with one another. Here is how they are defined.


Voltage can be defined as the speed at which an electrical current carries electrons past a specific point.

Experts like to use the analogy of flowing water to show the difference between different units of measurement related to electricity. Imagine a flowing river. The steeper the river descends, the faster it moves. If it's moving along a relatively flat surface, it will move slower. But if that river drops over an edge like a waterfall, it moves faster.

When it comes to electricity, the faster the speed the electrical current carries electrons, the higher the voltage.


Abbreviated as "amps," amperage is different from voltage. It represents the strength of an electrical current.

To continue our river analogy, amperage is not about speed. It's about volume. Imagine a wide river. It carries a larger volume of water past a specific point at any given time.

In an electrical circuit, amps measure the volume of the electrical current -- not the speed -- of electrons present at a given moment.

A home dishwasher might have a rating of 10 amps. That is referring to the volume of the electrical current at which that machine is designed to function. A bolt of lightning, in comparison, measures approximately 20,000 amps!

What's more dangerous in your home electrical system?

The river analogy is helpful in determining the danger of voltage versus amperage.

A river with high voltage, but low amperage can be represented by a narrow, small river flowing almost completely vertical. Imagine the tiny trickle of a waterfall. That water is moving fast as it falls to the ground, but the volume of water is too little to put you in danger.

A giant river that is deep and wide, on the other hand, has a higher likelihood of hurting someone caught in it. This represents a current with high amperage, but low voltage. Even though the current is moving slowly, the volume is still dangerous.

So it's amperage we have to be careful of. Variance in the level of amperage can cause different effects on our bodies. A milliampere is one-thousandth of an ampere or amp and here's how different amounts can affect us:

  • 1 to 10 milliamperes: A small shock -- or no shock at all -- is felt.
  • 10 to 20 milliamperes: Shock is painful, but muscle control isn't lost.
  • 20 to 75 milliamperes: Serious shock is felt that can cause a loss of muscle control and painful jolts. The victim is unable to let go of source of shock.
  • 100 to 200 milliamperes: Uncoordinated twitching of ventricles in the heart occurs, often resulting in death.
  • More than 200 milliamperes: Severe burns and muscle contractions occur. Internal organs can be damaged, including the heart.

To illustrate how dangerous your home electricity can be, the above numbers are far less than a standard household circuit. A household circuit that supplies your outlets and switches with power carries a whopping 15,000 to 20,000 milliamperes!


A watt is the rate of power flow. It's derived by multiplying voltage and amperage to measure the power actually generated within your electrical system.

When you multiply the volume of the electrical current (voltage) by the speed at which the electrical current is moving (amperage), you calculate its rate of power (wattage).

How does the electricity in your home electrical system work?

It all starts with atoms. Atoms are made of three smaller parts. Protons have a positive charge. Neutrons have a neutral charge. And electrons have a negative charge.

There are two important things you should know about atoms as they relate to electricity. First, the type of atom is determined by the number of protons, neutrons and electrons. Second, protons and neutrons exist in the nucleus, while electrons buzz around the outside of a nucleus like moons orbiting a planet.

Some atoms have a property where they temporarily take electrons from other atoms. This give-and-take is electricity. Not all atoms have this property, however.

Atoms with that property tend to be metal atoms. This is why metal is a good conductor of electricity. Electricity flows through metal as its electrons move from one atom to another.

Atoms without this give-and-take property are insulators. The elements that make up rubber are insulators which is why metal wires are often covered win a rubber protective layer. That keeps the current of electricity flowing in the correct direction and stops it from flowing through the wire and electrocuting us.

Electricity works by getting a bunch of conductor elements together to create a current of electricity. Insulator elements keep the current flowing in the direction you want. Once you control the direction the electrons are moving, you can use them to power anything from a lightbulb to an electric car.

Resistors and transformers in your home electrical system

Not all conductors conduct electricity equally well. Some elements are better conductors than others and that's a good thing for us. You don't want your electrical current to move as fast as possible. A lightbulb, for example, will burst if you try to force too much electricity through it.

That's why conductors with a certain amount of resistance are sometimes used.

The slower a conductor is at moving electrons, the more resistance it has. A faster conductor has less resistance. The wire leading to that lightbulb, for example, should have some resistance.

There are also items called resistors. They control the amount of electricity flowing through a circuit. This happens because they are made of elements with higher resistance than that circuit's wires. Resistors act as a dam that ensures your lightbulb, charging phone or appliance doesn't get more electricity than it can handle.

Transformers can work like resistors, or they can do the opposite. They are also able to increase the voltage in your system if necessary.

From the power company to your home

Electricity flows over wires and through switches and transformers from your electrical utility company's generating plant all the way to your home's main panel.

Your main panel is also known as your central breaker panel, or your fuse box. It directs electricity through one of a number of separate circuits or fuses to a specific wire. That wire is connected to a lightbulb, appliance or some other item. Once the electricity reaches that specific item, it is sent via another wire back to the main panel to be used again.

Generally speaking, a fuse from your main panel corresponds with a specific appliance in your home. That isn't always the case, however.

Some appliances require so much voltage that two breakers work together to provide the necessary power. Other circuits provide electricity to a number of -- as many as 20! -- lights and plug-in outlets.

How your home electrical system can go wrong

From the power company to your lightbulb, there are many connections along these paths that can be disrupted or fail.

The power company itself can have trouble getting power to your home. Broken lines, storms, an overburdened system caused by extreme weather and a host of other reasons can all cause your home to lose power.

This is one reason it pays to visit our website to learn more about generators that can ensure your backup power needs are covered.

There are also issues that can arise when electricity reaches your home system. Your main panel's breakers and fuses are designed to interrupt the electrical current if it approaches a dangerous level. Connections at the meter or main breaker can fail or become unreliable. This could disrupt some power in your home or even damage your home.

Be safe when working on your home electrical system

If you want to investigate a problem with your home's electricity on your own, there are some important safety rules to follow.

Always turn off the power to the circuit or device on which you will be working. Do this by switching off the breaker for that circuit in your main panel.

Don't assume you turned off the correct breaker, though. Confirming the power is off is important and can be accomplished by utilizing a non-contact voltage tester.

It's also important to post a warning note on your main panel, so others know not to turn it back on while you're working.

You should avoid wet areas when working around electricity. If its damp or wet outside, wear rubber boots and gloves as insulators from shock. Dry your hands before grabbing a cord, and plug in power tools and appliances into a ground-fault circuit-interrupter outlet.

You'll also want to use an insulated fiberglass ladder instead of an aluminum ladder any time you're doing electrical work.

Your home electrical system could use a backup plan

With everything that can go wrong in your electrical system, consider having AlltimePower help find a backup power source right for you.

Our professionals help you determine what size generator your home needs and what type of fuel is best for you. They can also help you find a reputable generator dealer in your area.

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