Key Questions
The following key questions are answered in this module:
What is a GFCI?
A Ground Fault Circuit Interrupter, or GFCI, is a safety device used in electric circuits. GFCIs are built into electrical outlets and they work by comparing the incoming current on the hot side with the outgoing current on the neutral side. They should be equal. GFCIs protect people from electric shock injuries and also protect the outlets, wiring, devices, and appliances from damage caused by overheating and fires due to ground faults and shorts.
What is an AFCI?
Arc Fault Circuit Interrupter, or AFCIs, also sometimes called Arc Fault Detection Devices, or AFDDs, are designed to detect and protect against potentially dangerous arc faults in addition to short circuits and overloads.
What are the three types of wires used in building electrical circuits?
The three types of wires used in building electrical circuits are hot, neutral, and ground. Hot wires (usually black) deliver current, while neutral wires (usually white or gray) create the current's return path. Ground wires (green or bare copper) prevent electrical fires and socks by providing an alternate safe path for the current.
What are the hazards of working on energized equipment?
Arc faults and arc flash are two potential hazards of working on energized equipment. An arc fault can occur when a conductive object contacts and bridges two conductors or a conductor and the ground. For voltages above 120v, this arcing can be in the form of an arc flash, where components explode violently.
When replacing an electrical receptacle, what is the correct wiring configuration?
The correct wiring configuration for an electrical receptacle is hot (black or colored) wires attach to brass screws, neutral (white) wires attach to silver screws, and green (ground) wire attaches to green screws.