Electrical
Learn the basics of electrical work, what's safe to DIY, what you need to do the work safely, and when to call in pro.

Homeowner's Guide to Electrical Systems

If your electrical systems are installed incorrectly, it's not just a minor inconvenience. Depending on where you live, it can have near-catastrophic consequences. Poorly installed electrical systems can lead to fires and generally dangerous conditions.

Of course, not every electrical problem is life-threatening. Homeowners can do minor electrical work, from replacing outdated outlets to installing energy-efficient appliances. But for any major remodel, you should consult an electrician to ensure your home's electrical system is suitable for the new appliance or system.

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Electrical Systems in a House

The electrical system in a home controls the flow of electricity and provides power to outlets, lights, and appliances. Understanding the basics of how electricity works is key for homeowners to maintain a safe, functional electrical system.

Electricity is the flow of electrons between atoms. This flow of electrons, measured in amperes, creates an electrical current that powers devices. The force or pressure driving the current is called voltage, measured in volts. Electricity flows in a loop from the power source through wires and devices and back to the source.

Components like switches, outlets, breaker boxes, and transformers all work together to regulate and control the electrical flow throughout a home. The breaker box, also called the service panel, acts like a command center, receiving electricity from the utility company and distributing it to circuits in a home through wiring.

The main service panel, or breaker box, controls and protects a home's entire electrical system. It is normally located outside or in the garage area. The service panel connects to the high voltage service wires that bring electricity from transformer lines into the home.

Inside the breaker box are circuit breakers that protect each circuit in the home. The breaker box takes the high-voltage power and steps it down to a normal 120-volt current that can be used to power lights and appliances. The breakers will trip and shut off if a circuit becomes overloaded, preventing fires or damage.

A qualified, licensed electrician should install and maintain the breaker box. Homeowners should not attempt to modify or rewire the service panel. Checking for tripped breakers during an outage and replacing faulty breakers are about the extent of DIY service panel maintenance.

The home electrical wiring system carries current to wall outlets, light switches and fixtures, and appliances throughout the house. Copper wiring is most common, though aluminum may sometimes be used.

Electrical wiring comes in a range of wire gauges or thicknesses. Gauge sizes range from 14 (the thinnest) to 6 (the thickest). The lower the wire gauge number, the thicker the wire, which allows it to safely conduct more electricity. Each circuit has a designated amperage capacity it can handle based on the wire size.

In addition to hot wires that carry 120 volts of power, circuits also have neutral "return" wires and ground wires for safety. Different colored plastic insulation surrounds each type of wire. White is for neutrals, black is for hot, and green is for ground wires. Proper connections are vital for a safe system.

Along with wiring, simple switches and outlets are part of basic residential electrical systems. Light switches turn lights, fans, and appliances on and off. Duplex receptacle outlets provide plug-in points to power electronics and devices throughout a home.

Other common electrical fixtures are ground fault circuit interrupters (GFCIs) and AFCIs (arc fault circuit interrupters). GFCIs measure current flow and quickly shut off power to a circuit if there is an imbalance or fault, helping prevent shocks. AFCIs prevent fires by detecting hazardous electrical arcing faults.

Special high-voltage outlets may also be installed to supply power for large appliances like dryers, ranges, and air conditioners that use 220-240 volts instead of the standard 120 volts. Proper wiring, grounding, and overcurrent protection are essential for outlet safety.

In addition to the basic wiring, many homes also have specialty electrical systems that serve specific purposes:

  • Whole house surge protectors help protect sensitive electronics from power spikes and lightning strikes. They are installed at the breaker box.
  • Home theater wiring deals with the HDMI, speaker, and electrical needs for a surround sound TV setup and media components. In-wall speaker wires, component shelves, and hidden wires for a clean look are part of these systems.
  • Security systems have sensors on doors/windows, motion detectors, control panels, and surveillance cameras that are wired throughout a home. Low-voltage wiring is typically used.
  • Smart home technology like video doorbells, smart thermostats, voice control assistants, and automated lighting involves integrating electronics through wireless networks or wiring.

Common Electrical Problems and Solutions

Electrical issues like tripping breakers, flickering lights, and power loss to outlets or appliances point to potential problems that need attention.

An electric circuit breaker
Image credit: Adobe Stock

Fuses/Breakers Tripping

Circuit breakers are designed to trip and cut power to a circuit when it becomes overloaded. This overload can be caused by plugging too many devices into outlets on a circuit or an appliance pulling more amperage than the circuit can handle.

If a breaker keeps tripping repeatedly, unplug some devices on the circuit and/or relocate devices to other outlets on different circuits to help reduce the electric load. Reset the tripped breaker to restore power. If the breaker continues to trip frequently, it likely indicates a deeper issue that requires an electrician to investigate and repair.

Flickering Lights

Lights that flicker, dim, or brighten sporadically typically mean there is a loose or faulty connection somewhere in the electrical system. This could occur at a light switch, the light fixture, or an outlet.

Loose connections can generate heat and arcing between wires, which poses a fire hazard if left unaddressed. Check and tighten all wiring connections on the affected circuit, but if the flickering persists, you likely need to call in an electrician to identify and replace the failing connection or aging wiring causing the issue.

No Power to Outlets

Image Credit: Adobe Stock
Image Credit: Adobe Stock

When an electrical outlet suddenly stops working, there are a few common culprits to check first. Start by checking for a tripped GFCI outlet that may have cut power due to detecting a fault. The reset button on the GFCI outlet will need to be pressed to restore power if this is the cause.

Also, check your breaker box for any tripped circuit breakers protecting that outlet and reset them. If the outlet still does not work, faulty wiring leading to open connections or a failed outlet is likely the issue. Professionally replacing the old wiring or faulty outlet is the proper solution.

Other Issues

Certain electrical issues point to immediate, dangerous wiring hazards that require emergency attention. Sparking from outlets or switches indicates loose wire connections, and shocked outlets mean improper grounding. Burning smells from fixtures or buzzing sounds signal overheating wires.

In these concerning situations, quickly shut off power at the breaker box and call an electrician right away. Do not use the switches or outlets. The wiring needs to be thoroughly inspected and any damaged wiring replaced. Failure to address these red flags can lead to fires.


Electrical Safety Tips

Follow these tips to safely handle minor electrical issues and help prevent hazards in your home:

  • Don't overload outlets. Too many devices on one outlet or circuit can lead to overheating, which can start fires. Unplug or relocate devices to reduce overload.
  • Avoid exposing outlets to water leaks and flooding. Immediately turn off power if outlets or electronics get wet. Water conducts electricity and poses shock risks.
  • Inspect appliance power cords and extension cords for damage. Replace cords with cracked insulation, exposed wiring, or loose plugs. Do not try taping damaged cords.
  • Install ground fault circuit interrupters (GFCIs) in kitchens and bathrooms. laundry rooms, and outdoor areas. GFCIs provide important shock protection. Test them monthly.
  • When doing any DIY electrical work, turn off the power at the breaker. Use safe practices and request inspections. Research local permit requirements before starting electrical projects.
  • Hire a licensed electrician certified in your area for any major electrical work like rewiring, service panel upgrades, or installing new circuits. They ensure code compliance and safety.

When to Call an Electrician

While simple electrical repairs like changing a light switch or outlet may be reasonably DIY-friendly for some homeowners, larger electrical issues often require calling a professional electrician for service:

  • If you have very old wiring in your home that may be knob-and-tube wiring, it needs to be inspected and likely replaced. This old wiring is outdated and poses fire risks.
  • Upgrading an electrical service panel or fuse box requires electric load calculations to size it properly. Then the power must be safely transferred and reconnected. This complex job is best left to the experts.
  • Rewiring a whole room or entire house must be done properly with in-wall wires correctly sized for each circuit. New connections and outlets require permits and inspections.
  • Adding new high-power 240-volt circuits for a kitchen appliance upgrade, hot tub, EV charger, or workshop equipment is hazardous DIY work is better left to experienced electricians.
  • Installing a whole house surge protector or connecting a standby generator involves special considerations best handled by professionals. Improper wiring can damage systems.
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