Understanding Electrical Faults (GFCI and AFCI)
Have you ever heard the terms GFCI and AFCI? If you haven’t - or you have, but you are still unsure how these work - you’ve come to the right place. Understanding what’s happening behind the scenes in the house’s wiring doesn’t take a college degree and can be handy information to have.
Specifically, GFCI (ground-fault circuit-interrupter) and AFCI (arc-fault circuit-interrupter) are both designed to save lives and prevent severe damage to the home when accidents happen. Now to understand how these devices work to protect your home, we need to delve a bit into electrical faults and how to prevent them.
What are electrical faults?
An electrical fault occurs when a current strays from its intended path, the circuit. This usually happens due to a sudden change in resistance along the path. Since a current naturally aims towards the path of least resistance, it will arc towards it and cause a fault in the system if a new one opens.
The most common faults in the circuits are:
Overcurrent flow: This fault happens when the circuit has more amperage than it’s designed to handle. This fault commonly trips your circuit switches to prevent further damage to the system. It can happen if too many devices are connected to a single circuit or a sudden surge of electricity passes through it (such as from a thunderstrike).
Ground fault: A ground fault happens when the current finds another way to flow into the ground, most commonly through a puddle of water or other material that conducts electricity (such as the human body). Ground faults are dangerous because all the electricity flows from the outlet into the ground through whatever means necessary, causing severe damage along the way.
Arc fault: An arc fault can happen if a current arcs between two conductors. Arcing produces a high-voltage charge that can ignite nearby dust or gases. Loose connections, uninsulated wires, and broken wires are the most common causes of arc faults.
While most circuit switches can deal with an overcurrent flow, more modern designs must handle ground and arc faults. This is where GFCIs and AFCIs take over and reduce the chances of electrical faults.
GFCIs
GFCIs immediately remove power from the circuit when they detect a straying ground fault. The most common designs look similar to a regular outlet but have systems to catch a leaking current of about four to six milliamps to the ground. This is important because it takes approximately 10 milliamps passing through the human body to stop the heart.
GFCI protection is most commonly placed in rooms with running water and high humidity, such as bathrooms, laundries, kitchens, or garages.
AFCIs
AFCIs detect sudden surges in the circuit that can happen when the current arcs between wires and immediately de-energizes the system to prevent further damage.
AFCIs are most commonly installed in the electrical panel alongside fuses or switches.
Check if you’re protected
Since GFCIs and AFCIs are more modern inventions (the former was introduced in the 1960s, and the latter in 2002 for residential buildings), not all houses will have these safeguards installed. Contact a professional electrical service for a thorough inspection and installation of these life-saving devices.
When you need a licensed electrician for commercial or residential electrical needs, call Zimmerman Electric at 310-378-1323.