AnniVersAry issue - Inside Edison - Edison International

Breaking Down
Electrical
Outlets
Distribution
board
Grounding
wire
Grounding rod
To power an appliance, electricity
from a grounded three-slot outlet is
sent via a live wire (colored red in
the illustration) connected to the
outlet’s smaller vertical slot to the
inserted appliance plug’s live prong (red). Electricity
flows through the appliance back to the
plug’s neutral prong (white) and through the
outlet’s larger slot to a neutral wire. Both wires
connect to the distribution board, also known
as the circuit breaker panel or service panel.
A grounded outlet provides additional safety
by allowing another path for the flow of electricity
under hazardous conditions. Many appliance
plugs have a third rounded prong (green), called
the ground pin, which usually attaches via a
wire to the appliance’s metal casing. This plugs
into the outlet’s third slot, which is connected to a
grounding wire that attaches to the distribution
board. If the appliance malfunctions and becomes
electrified, the electricity is carried through the
grounding wire to the distribution board where it
trips the circuit breaker, stopping the flow of electricity
and removing the hazard.
Neutral
wire
Grounding
wire
Live
wire
Service
box
Live prong
Ground pin
Neutral prong
As a safety precaution, household electrical systems in the U.S. are required to
be connected to the ground. The distribution panel is connected to a rod driven
into the ground by a grounding wire that runs through the service box.
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