Electrical Devices

Electrical Devices -1

Fuse
Ground
Fault/ground fault
Receptacle
Plug
A fuse is a protective device that can open a circuit if there is too much current flowing through
it. Since a fuse melts when there is too much current, it protects the rest of the circuit from being
damaged.
Ideally, the fuse will be the weakest point in the circuit and will be the only place that a circuit
will melt.
If a circuit is grounded, it means that the circuit is physically connected to earth ground by a
conductor. This connection to the actual ground, or dirt outside, allows unwanted electricity to
flow to the earth.
Being grounded can prevent the buildup of static electricity and can help prevent electric shock
from faults.
A fault is temporary, unexpected current in a conductor. A short circuit is a type of fault that
allows damaging amounts of current to flow through a circuit.
An arc flash is a type of short circuit.
A receptacle is an outlet for electricity. You have these all over your house and plug items such
as irons and vacuum cleaners into them.
A plug, then, is what gets plugged into a receptacle, allowing an electrical device to get
electricity.


Load
Personal protective equipment (PPE)
Panel board
Transformer
A load is any device that converts electrical energy into light, sound, motion, or heat. One
example would be a light bulb.
A load gives resistance to the current in a circuit.
A light bulb is a load in a circuit that converts electricity into light.
Personal Protective Equipment, or PPE, is clothing and other items that are worn to help keep
you safe when working near arc flash hazards. PPE protects you from the intense light, heat,
sound, and explosion of an arc flash.
The type of PPE required is determined by the amount of voltage and current available. We will
cover determining what type of PPE is needed later in the training.
A panel board is a cabinet containing a group of circuit breakers, fuses, and short circuit
protection devices for lighting, appliances, or other circuits; it is usually placed in or on a wall
with access to the front through a panel door.
You have an electrical panel in your house where the circuit breakers are located.
Transformers help electricity travel over long distances without losing much energy.
Transformers are the only way to get electricity cheaply to your house.
Transformers allow electricity to get to your house by taking the high‐voltage, low‐current
electricity from the power lines and turning the electricity into 120 volt, higher current
electricity.

Transformers are important when learning about arc flash because one of the key components
of how bad an arc flash will be is how much current is available from the transformer supplying
the electricity.