Basic Electrical Materials Part 2 of 2 - Introduction to Electrical Wiring - Trades Training Video

Summary

This video script offers an in-depth look into electrical materials used in residential installations. It covers wire types, conduits for protection, and their installation requirements. The script explains different devices like duplex receptacles, GFCI and AFCI outlets, and switches, including three-way switches. It also highlights safety features and the importance of cover plates for aesthetics and protection. The video aims to educate on the language and parts of electrical systems in residential structures.

Takeaways

• 🔌 **Conduit Usage**: Conduits protect wires that are not enclosed or concealed in walls or structures and come in various materials like metal or plastic.
• 📏 **Rigid Conduit**: Rigid conduits are available in metal or plastic and can be bent by hand for metal versions, while plastic requires fittings.
• 📐 **Conduit Sizes**: Sizes range from three-quarter inches up to six inches or larger for commercial and industrial use.
• 🌡️ **Conduit Fill Limit**: Only 40% of the conduit's internal space should be filled with conductors to allow for heat dissipation.
• 💧 **Flexible Conduit**: Allows for flexibility and can be weatherproofed with special ends to keep out elements.
• 🔩 **Conduit Termination**: Various fittings are used to terminate conduits, differing by material and conduit type.
• 🛠️ **Securing Conduits**: Conduits must be secured with staples or straps to ensure stability.
• 🛡️ **Armored Cable**: A type of flexible conduit with an aluminum wrap around the conductors for added protection.
• 🏠 **Devices in Electrical Systems**: Devices like duplex receptacles, GFCI, AFCI, and switches are used to control and manage electricity.
• 🔒 **Safety Features**: GFCI and AFCI outlets provide safety by monitoring current flow and resistance to prevent electrical shocks and fires.
• 🖼️ **Cover Plates**: Used to finish electrical installations, providing insulation and a finished look while preventing shocks and fire spread.

Q & A

What is the purpose of conduit in electrical installations?

Conduit is used to protect electrical wires that are not enclosed or concealed within a wall or other structure. It comes in various forms, shapes, and sizes, and is available in metal or plastic.

How is rigid conduit different from flexible conduit?

Rigid conduit is available in metal or plastic and can be bent by hand for the metal version, while the plastic version requires fittings to change direction. Flexible conduit, on the other hand, can take any shape or direction and allows for some flex.

What is the maximum fill percentage for conductors inside a conduit?

The inside of a conduit should not be completely filled with conductors. Only 40% of the inside space should be filled with conductors, leaving 60% as air space for heat dissipation.

What is the purpose of the space left inside the conduit?

The space left inside the conduit allows the conductors to 'breathe' and dissipate heat, preventing overheating and ensuring the safe operation of the electrical system.

What is armored cable and how does it differ from other types of cables?

Armored cable, also known as MC cable (metal clad), has a wrap of aluminum around the conductors, offering high protection. It serves as both the wire and conduit, providing a strong and flexible cable suitable for various installations.

What is the difference between a duplex receptacle and a single pole switch?

A duplex receptacle is a type of outlet with two plugs available, typically used for power outlets. A single pole switch is a simple on-off switch used to control one or multiple fixtures from a single location.

What are the safety features of GFCI and AFCI outlets?

GFCI (Ground Fault Circuit Interrupter) outlets detect imbalances in current flow, which can indicate a ground fault, and shut off immediately to prevent electrical shock. AFCI (Arc Fault Circuit Interrupter) outlets monitor for differences in resistance that could lead to a fire and also shut off the power if such a condition is detected.

How often should GFCI and AFCI devices be tested?

GFCI and AFCI devices should be tested periodically using their test button to ensure they are functioning properly. It's a good practice to do this occasionally, especially in residential settings.

What is the purpose of wire staples in electrical installations?

Wire staples are used to secure Romex wire to framing, ensuring it is held in place within every 12 inches near a box and every 54 inches in other areas, providing safety and organization.

What is the role of cover plates in electrical installations?

Cover plates are used to finish off devices in junction boxes, providing a finished look, insulating against potential shocks, and containing any fire that might occur within the junction box.

Why is it important to know the language of electricity in the electrical trade?

Understanding the language of electricity is crucial for clear communication on the job site, especially in skilled trades like electrical work, to ensure safety, accuracy, and efficiency in installations and repairs.

Outlines

00:00

🔌 Conduit and Wiring Protection

This paragraph discusses the use of conduit to protect electrical wires that are not concealed within walls or other structures. Conduit comes in various materials like metal or plastic and sizes, with rigid conduit being a common type that can be bent by hand for metal or requires fittings for plastic. It's crucial not to fill the conduit completely, allowing for 40% conductors and 60% air space for heat dissipation. The paragraph also covers flexible conduit, which is weatherproof and can be bent to shape, and the various fittings used to terminate conduits at junction boxes or devices. Different types of conduit fittings are mentioned, such as those for EMT conduit and PVC rigid conduit, including liquid-tight connections and the use of O-rings for sealing.

05:01

🛠 Electrical Cables and Devices

The second paragraph delves into different types of electrical cables and devices. It introduces armored cable, which is a flexible conduit with an aluminum wrap around the conductors, providing protection and serving dual purposes as both wire and conduit. The paragraph explains the standard 14-gauge setup with color-coded wires for hot, neutral, and ground. It then moves on to discuss outdoor cables or UF cables, which are designed for burial with a weather-resistant jacket. The discussion continues with devices like duplex receptacles, which are common outlets with three-prong arrangements for hot, neutral, and ground connections. Safety features such as ground fault circuit interrupter (GFCI) and arc fault circuit interrupter (AFCI) outlets are highlighted for their ability to detect electrical anomalies and prevent shocks or fires.

10:03

🛑 Circuit Protection and Switches

This paragraph focuses on circuit protection devices and switches. It mentions GFCI and AFCI outlets in detail, explaining their roles in detecting current imbalances and loose connections respectively, which can prevent electrical shocks and fires. The paragraph also covers the importance of testing these devices regularly and what to do if they continually trip. The discussion then shifts to switches, starting with basic on-off switches and their wiring method. It introduces three-way switches, which allow control of a light fixture from two different locations, and explains the difference between single-pole and three-way switches in terms of wiring and terminals. The paragraph emphasizes the importance of cover plates in electrical installations for aesthetics and safety, protecting users from shocks and containing any potential fire within the junction box.

15:04

🏗 Electrical Installation Materials and Safety

The final paragraph provides a review of electrical materials used in residential electrical systems, emphasizing safety and aesthetics. It covers service wires, meter bases, load centers, circuit breakers, and special safety breakers like GFCI and AFCI. The paragraph explains the use of Romex wire, its color coding, and the importance of securing it with wire staples. Junction boxes are discussed as enclosures for wire splices and device installations. Duplex receptacles are highlighted as points of use for powering appliances, with a focus on their safety features. The paragraph also touches on single-pole and three-way switches, wire nuts for securing spliced wires, and the role of cover plates in finishing electrical installations. The video concludes by encouraging viewers to learn the language of building, especially for skilled trades like electrical work, and to explore the vast array of parts and variations in the electrical trade.

Keywords

💡Conduit

Conduit is a protective tubing used to encase electrical wires. In the video, conduit is presented as essential for protecting wires that are not concealed in walls, shielding them from damage, wear and tear, or exposure to elements. Examples include rigid metal or plastic conduits, as well as flexible, liquid-tight versions for weatherproof applications.

💡EMT Conduit

EMT (Electrical Metallic Tubing) conduit is a lightweight, thin-walled metal tubing used to protect electrical wiring. The video highlights its ease of use, noting that EMT can be bent by hand and is used for indoor applications where protection from physical damage is necessary.

💡Flexible Conduit

Flexible conduit is a type of conduit that can be bent and shaped to accommodate different installation paths. It is weatherproof and used in environments where rigid conduits cannot easily follow the wiring path. The video mentions liquid-tight flexible conduits, which are resistant to outdoor elements and UV exposure.

💡Armored Cable (MC)

Armored cable, also known as metal-clad (MC) cable, combines electrical conductors and a protective metal sheath. The video explains that it serves as both wires and conduit in one unit, offering protection and flexibility. It is commonly used in commercial applications and requires special fittings to terminate.

💡Ground Fault Circuit Interrupter (GFCI)

A GFCI is a safety device designed to prevent electrical shock by shutting off power if it detects an imbalance in the current flowing in and out of the circuit. The video emphasizes its importance in wet areas, like bathrooms and kitchens, to protect against accidental shock. It includes a reset button for restoring power after a trip.

💡Arc Fault Circuit Interrupter (AFCI)

An AFCI is a type of electrical safety device designed to prevent fires caused by arcing faults in wiring. The video explains that AFCIs detect problems related to resistance, such as loose connections, which could lead to electrical fires. It also includes test and reset buttons, like GFCIs.

💡Duplex Receptacle

A duplex receptacle is a standard electrical outlet with two plug-in points. The video explains its three-prong design, including the hot, neutral, and ground connections. It highlights how duplex receptacles are the primary means of powering appliances in residential electrical systems.

💡Switch

A switch is a device used to control the flow of electricity to a fixture or appliance. The video describes how a single-pole switch functions by breaking or completing a circuit. It also touches on three-way switches, which allow multiple control points for the same fixture, commonly used for convenience in large rooms or staircases.

💡Junction Box

A junction box is an enclosure that houses wire splices and electrical connections. The video emphasizes the junction box's role in protecting wires, containing any potential fire or arcing, and providing a location for installing electrical devices like switches or outlets.

💡Romex Wire

Romex wire is a type of non-metallic electrical wire commonly used in residential wiring. The video explains that Romex comes in various gauges and conductor counts, depending on the electrical needs of the circuit. It is held in place using wire staples and is a staple of home electrical installations.

Highlights

Introduction to conduit and its purpose: protecting wires when not enclosed in walls.

Explanation of rigid conduit in both metal and plastic forms, highlighting their durability.

Description of flexible conduit and its ability to follow various paths due to its flexibility.

Detailed safety requirements for conduit, including the 40% fill rule for conductors.

Discussion on liquid-tight and weatherproof conduit designed for outdoor applications.

Key explanation on the use of armored cable (MC) for added protection and durability.

Importance of using fittings to terminate conduit and armored cable safely into junction boxes.

Demonstration of how a duplex receptacle functions with clear guidance on wiring hot, neutral, and ground connections.

Introduction to safety devices: Ground Fault Circuit Interrupters (GFCIs) and Arc Fault Circuit Interrupters (AFCIs).

Explanation of how GFCI outlets protect against electrical shock by sensing current imbalances.

Overview of AFCI outlets and their role in preventing fires caused by loose connections.

Simple on/off switches and their wiring structure, along with a brief overview of three-way switches.

Clarification of the difference between a single-pole switch and a three-way switch for controlling fixtures from two locations.

The significance of cover plates: both for aesthetics and safety, preventing electrical shock.

Final recap of common electrical materials such as wire staples, Romex wire, circuit breakers, and the importance of secure wiring.

Transcripts

hello everybody welcome back to our

electrical materials video

let's get right into it with some more

parts

to start with we talked about wire that

is going to be

enclosed or concealed in a wall or in

other spaces

in a structure what do we do if we're

not

hiding or concealing that wire we need

to protect it

we're going to do that with a material

we call conduit

conduit can come in a lot of different

forms

shapes and sizes we're going to start

with rigid conduit and rigid conduit is

available

in metal or plastic i've got a couple

examples

of a three-quarter conduit here we would

run

our cables through these conduit and

then it would protect that cable from

anything that would happen to it whether

that would be fasteners or just wear and

tear

or exposure to weather even so you see

here

this is three-quarter metal emt conduit

and three-quarter

outdoor this is a pvc conduit and

they're the same size

inside this is an inside diameter

measurement

keep in mind conduit is going to come in

long lengths

the metal version we can bend by hand

and the plastic version we're going to

have to use

different fittings to get it to follow a

certain path

conduit sizes are going to range

anywhere from three-quarter

up to six inches they can even be larger

if we're looking at

commercial installations and some

industrial situations

and the inside of the conduit cannot be

completely full with our conductors we

need to only

fill this inside space of this conduit

up to 40

percent the other 60 percent needs to be

air space

we need those conductors to breathe they

need to dissipate heat

so we need to leave some space in there

another type of conduit other than rigid

conduit

would be flexible conduit this conduit

is going to take whatever shape or

direction

we want to put it in and it's going to

allow some flex so we can run

our conductors through this conduit this

type

is also weather proof so it's going to

be they call it liquid tight

when you put special ends on this

conduit

it's going to keep all the weather out

this conduit is also

like the rigid plastic is going to be uv

resistant so this can be exposed to

sunlight and be

out in the elements there's a whole

array of different type of pieces and

parts we will use

to terminate the ends of the conduit

into a junction box

to a specific device those parts

are going to look different depending on

the type

of conduit we're using and the material

that conduits made out of

here you see some examples and on the

presentation there are some duplicates

of these examples

the rigid type the one at the bottom

right is for an emt conduit that's going

to be for the metal pipe

it has a set screw we're going to

tighten that screw up to clamp it to the

pipe

that's going to terminate the conduit we

can then run our cables through it

there's also on a typical end

for this kind of conduit is going to

have a threaded

end and the ends either going to get

threaded

into the box or it would go through a

knockout in the box then we would

put a nut on the end to secure it to the

box

this is a 90 degree turn for a liquid

tight connection

we take our flexible conduit we would

attach it to the end

of this piece here that's going to seal

up this end

then this end would terminate in a box

and it also has

the same nut on the end if you look

close

also it has an o-ring

this is a rubber o-ring that is going to

allow

that fitting to seal up against the box

that's what makes it liquid tight

there's a lot of other variations of

hardware

some to make turns with ent rigid

conduit

some would be a coupler like the top

right that would be to connect two

straight pieces together

it has the same set screws that we

talked about before and the one on the

bottom

is a version of a 90 degree turn we

could use with a pvc rigid conduit

now that we have our conduit run in the

path that we need

we have to secure that conduit to make

sure that all of this holds together

just like our cables and our wire

staples

these straps are going to hold that

conduit tight you might see a two-hole

version or a one-hole version

the only difference is going to be the

amount of fasteners we use

to secure them an armored cable is a

type of a flexible conduit

and this cable has a

wrap of aluminum around the conductors

that are already inside of it

as you can see i have some limited

flexibility

in this cable based on the way it's made

and the

cables or the conductors on the inside

are very well protected

this is a very strong type of cable

this serves as your wires and

your conduit at the same time so we have

a typical

14 gauge setup here with our three

or our two conductors and our ground as

you can see

our ground is a green wire so

this has an insulation around it that's

very common and we consider

green for ground we have our black which

is our hot

and then we have our white which is our

neutral armored cable or what they call

mc which is metal clad cable is going to

take its own

special fittings so if we wanted to

terminate

the end of this cable into a box we'd

use something similar to this

that looks like our other hardware it

has this same set

nut on it and we can screw this into the

box

or we can add the nut to clamp it to the

box this is the way these go on you're

going to thread these in

around your conductors and this is going

to actually

thread into the cable where

you've cut it it's going to thread nice

and tight

now we have a good termination of an end

this fitting is also going to protect

the

insulation of these wires from this very

sharp

edge that we cut off of this armored

cable

another version of cable you might see

that's very similar to romex but has a

very different

characteristic to it is an outdoor cable

or uf

this would be an underground feeder

that's the uf

designation this cable has a special

jacket around it

that is molded around the conductors

that are inside

same gauge wire same insulation around

the inside conductors

it's just that it is a more weather

resistant and more

water tight situation this type of cable

can actually be buried in the ground

as long as the ends or bare ends of the

cable are

protected and dealt with properly

moving on from our conduit and our

cables we're going to get into devices

we've run all of the system of

conductors now we need to put them to

use

my first device to show you is going to

be a duplex receptacle

we're all very familiar with this this

is what we use

when we're trying to get power out of an

electrical system

this is a three-pronged outlet you might

hear it called an outlet i call it a

duplex

receptacle because it has two plugs

available

on it it has a three prong arrangement

which is going to have a narrow blade

that's going to be

our hot conductor it's going to have a

wider blade that's our neutral conductor

it's also going to have a ground prong

that's the more

round one this is a modern addition to

an outlet you might see an older one

that only has two prongs it will be

missing this ground

and on this receptacle if we look

at the side of it it's going to have

gold terminals

these terminals are going to accept a

wire end and as we

as we curve that wire end we can hook it

on that terminal we will then

tighten it up that's what's going to

deliver our electricity

to this outlet so we have on this side

we have

our our gold

terminals that's where our hot wire or

our black wire is going to go

on the other side we have silver

terminals

that's where our white wire is going to

connect

and then we also have a ground terminal

that's where our bare ground or our

green insulated

ground conductor will connect next up

we have receptacles available to us that

have safety features built into them

just like the breakers we talked about

earlier we have a ground fault circuit

interrupter

outlet and we also have an arc fault

circuit interrupter outlet

this ground fault they look very similar

you would

not even know the difference unless you

look very closely

what's different is the interior

circuitry of them and how they

operate and what they're looking for in

the circuit very sophisticated circuitry

in them

a ground fault is looking for current

variations

in the amount of current that's coming

into them and the amount of current

that's going

out of them if it senses an imbalance

in those two directions of current it

will turn this

outlet off immediately that's a safety

feature that could save you

from electrical shock these both

both versions of these will have a reset

button on them

so if they trip and often they can trip

for reasons

other than a person being shocked it's

looking for this condition and if it

trips

it will turn off the reset button will

reset

power to this it's important to mention

that if this

outlet is continually tripping it might

have gone bad or you might have a

problem with your wiring so

at that point we need to look into this

situation further

there is also a diagnostic feature on

this device

which is a test feature when you push

the test button

it's going to test the system to make

sure this device is working properly you

should do that every once in a while

if you have these installed in your home

a quick review of the terminals on this

device

would be that the gold ones are for our

hot or black wire

and then on the other side we have our

silver terminals those are for

our neutral wire it also will have

a ground terminal that's going to be

green that's for our bare copper

or our green insulated wire

here is our arc fault circuit

interrupter a whole different device and

what it's looking for

is problems in the circuit mainly for

differences

and problems with resistance which in an

electrical circuit

equates to loose connections that could

cause a fire so this particular one is

monitoring for that condition

if it sees or senses that condition it's

going to turn the power off

instantly it has the same test and reset

features that our ground fault did

next up we have a simple device we're

going to call a switch

often we need to control other devices

and we'd use this device to do it

it's a simple on off switch we're all

very familiar with it

and it works very simply let me explain

that

so this particular switch is

supposed to be or we understand it to be

oriented

so that on is up and down

is off that is the position we would

mount the switch in

when we installed this device it also

has fewer terminals than a typical

duplex receptacle

so if we look at the right side of this

single pole switch you're going to see

two terminals they're both gold

we can connect a hot wire to either one

of these

and i have a diagram to show you how

that works

so here we have a switch and we have a

simple light we're going to run

one wire in on one gold terminal that's

going to be a black wire

and one wire out also a black wire

to our fixture or our light when we

power up that first wire

it's going to send voltage or current

to our switch with the switch turned off

the light does not receive that energy

when we switch that switch on it's going

to

connect these two terminals and it's

going to let that

electricity flow through to the light so

when we turn it back off we're breaking

the connection between those two

terminals

that is the most simple version of a

switch that we have

we also have more complicated versions

of switches

this is an example of a three-way switch

the name's a little confusing

a three-way switch allows us to have two

different switches for one location

so if this was switch number one we

could also have switch number two

and they would both control the same

light fixture

or series of light fixture this is a

convenience feature that allows us to

put these switches

in two different locations possibly at

two different entrances

to the same room there's a lot more

complicated

wiring that has to happen to make a

three-way switch work

but i'll go through the basics of it the

difference between a three-way switch

and a single pole switch is that you're

going to have your two gold terminals

but you're also going to have a black

terminal and your

your feed wire which is either feeding

energy in

or letting the energy out of the circuit

is going to come in or out from this

black terminal the other ones we call

travelers these gold ones and they're

going to give us two different

paths for the circuit to follow we'll

get more into that when we get into the

skills exercise

about three-way switches i would like to

mention also that it has

a ground terminal that would be for our

bare wire or a green insulated conductor

to wrap things up with our electrical

installation we need to give

all of our systems a finished look we're

going to use

cover plates to do that and a cover

plate is going to do

two things it's going to make this

whole electrical system look finished so

any point that we're touching or come in

contact with

is going to look good the other thing

that a cover plate does

is it's going to insulate us from the

potential of shock or any of those bare

wires

inside of that junction box behind that

device it's also going to if there's any

kind of fire or

arcing in that junction box it's going

to help prevent

fire from spreading from that location

so

i have here some very basic low end

cover plates cover plates can get very

expensive and decorative

they all pretty much do the same thing

and even your most

basic cover plate is going to have to

meet a ul

listed criteria that keeps you the user

safe when we're talking about cover

plates

we're talking about aesthetics when we

get to this point in the installation we

want to make

this job look good a lot of the

aesthetics of the job

or quality of the job is installing

these properly so

you need these to be straight on the

wall you need to make sure that the

screws are in place

and that they match the cover plate that

they're being used with

and that there are no bows or warping to

the cover plate

that cause a problem when you're looking

at it

let's do a review of our electrical

materials

to start with these are aluminum

stranded heavy duty conductors we're

going to call

service wires every building will have

a meter base and a meter installed this

is going to allow us

to measure the amount of energy coming

in so that the utility company can build

a customer

a load center or service panel is going

to contain

all of the beginnings of the circuits it

will also hold

all of the breakers that we're going to

use to

service those circuits a circuit breaker

is a switch

and also has a safety feature built into

it that's going to allow us

to monitor the amount of amperage that's

going through a circuit

special safety breakers might be ground

fault or arc fault circuit interrupters

these offer extra safety features

romex wire comes in different gauges

it's also

color coded and has different amounts or

numbers of conductors

in it wire staples are used to hold

romex to framing

we're going to secure it within every 12

inches of a box and every 54 inches

everywhere else

junction boxes are enclosures that are

going to hold

wire splices any ends it's also going to

allow us a place to

install our devices duplex receptacles

are point of use plugs that we use to

power our appliances there's going to be

three conductors or three prongs for the

plug that's a ground

a hot and a neutral

afcis and gfcis which are arc fault and

ground fault circuit interrupters

are safety versions of our duplex outlet

these are going to measure

and they're going to monitor the current

flow and resistance

of the electricity and they're going to

shut off if we have any problems in the

circuit

single pole switches are simple switches

we use

to control one fixture or multiple

fixtures in one location

and three-way switches are going to

allow us to have two switches that

operate

a single or multiple fixtures from

two different locations wire nuts are

special clamps that are twisted

onto wire ends that are spliced together

to help hold them tightly

cover plates are used to finish off a

device

in a junction box to look good and also

to keep the user from getting shocked

and also to contain

any fire that might happen inside that

junction box

this is a list of terms used when we're

talking about electricity

and as always i like to stress this idea

of learning the language of building

and using it on the job site especially

when we're talking about skilled trades

like electrical

so i hope you've learned something about

some basic parts that are used

in a residential structure when we're

installing an electrical system

keep in mind there is an entire world

of other parts and variations of all

these parts

that you will see when you get further

into this trade

so i hope you've learned something get

further into this

i'll see in the next video

this video is a production of trade

skills you

all rights reserved