Key Electrical Terms Explained

Are you having trouble explaining what your problem might be? Can you see an issue but you have no idea what it might be? This glossary of terms can help you to better understand what’s going on and what you need to do to fix the issue.

Amperes – One key characteristic for measuring an electrical current, also often shortened to “amps.” An easy way to explain it is to envision electrical flow like a rushing river.

• Volts are the size of the river (how far across and deep it is)
• Amps are how fast that river is flowing
• Watts is a combination of both, measuring how much force that river could place on something like a dam or a waterwheel. 

Circuit – A closed loop connection between a power source and a device that needs that power. Circuits must be “closed” or fully-completed in order for the flow to run. Breaking that connection “opens” the circuit and kills the flow of power.

Circuit Breaker – An important safety device that shuts off power to one of your home’s circuits in the event that the power flowing through that circuit exceeds safe levels. Different breakers have different points at which they shut off, making them suitable for different areas of your home. Your panel contains roughly a couple dozen circuit breakers.

Fixture – Any electrical device that is directly wired into your electrical system. Outlets, lights, and ceiling fans are all examples of fixtures.

Generator – A machine that creates electrical energy, typically through the use of magnets. Connecting a generator to your home can provide you with a limited amount power when the public grid goes down. Generators typically come in portable and standby varieties.

GFCI – The GFCI outlet, or ground-fault circuit interrupter, is a circuit breaker that is designed to block electric power in the event of a ground-fault in under 1/40th of a second. A GFCI can help prevent electrocution. If a person's body starts to receive a shock, the GFCI senses this and cuts off the power before he/she can get injured. GFCIs are generally installed where electrical circuits may accidentally come into contact with water.

Ground – Typically this refers to a third electrical line that is connected directly to the earth. This is a key safety feature that prevents potential electrical problems from damaging devices or starting fires. When a device is said to be “grounded,” that means it is connected to this protection.

Meter – A piece of equipment that acts as the gateway between your home’s electrical system and the public electrical grid. Your meter tracks how much energy your home uses over a period of time, thus allowing your electrical utility provider to bill you for it. Tampering with or self-servicing your meter is against the law, so you’re best off leaving any issues with it to a professional.

Multimeter – A tool electricians use to measure all sorts of different characteristics throughout your electrical system, including voltage, amperage, resistance, wattage, and more.

Outlet – The name for a socket where you can plug a device in to connect it to power. These are most commonly found in your walls, but are occasionally in your floor or ceiling and sometimes can be multiplied through the use of a multi-outlet power strip.

Panel – Also often referred to as your “breaker panel,” “panel box,” “service panel” or “fuse box” by those who are old enough to remember when they contained fuses, your electrical panel is the heart and brain of your electrical system. This is where all of the various circuits connect to your home’s main electrical entrance and where all of your breakers are located. You’ll typically find this in your garage or in a closet near the front of your home. 

Switch – A small device that turns a circuit on and off by closing and opening the circuit. They are typically used for lights, but can control just about anything that they’re wired to. Dimmer switches can change the amount of power flowing through a circuit as well as turn power on and off.

Volt – Another key characteristic for measuring an electrical charge. See amperes for more detail.

Watts (or wattage) – Another key characteristic for measuring an electrical charge. See amperes for more detail. Wattage can also be used to describe how bright a lightbulb is, with more watts meaning a brighter light.