Construction
Electrical
Terminology
Electricians
Acknowledgments
Winnipeg Technical College and the Department of Labour and Immigration of Manitoba
wish to express sincere appreciation to all contributors.
Special acknowledgments are extended to the following individuals:
Manola Barlow, Independent contractor
Doug McKay, Instructor, Winnipeg Technical College
Recognition of Prior Learning Coordinator, Winnipeg Technical College
Funding for this project has been provided by The Citizenship and Multicultural Division,
Manitoba Department of Labour and Immigration.
Disclaimer
Statements and opinions in this document do not reflect those of Winnipeg Technical
College or the project funder, Citizenship and Multicultural Division, Manitoba
Department of Labour and Immigration. The information is gathered from a variety of
sources and is current and accurate as of the revision date noted. This information is
subject to change and will not be further updated. It is the responsibility of the reader to
seek current statistics and information.
Please contact the Winnipeg Technical College at 989-6500 or www.wtc.mb.ca if you
have questions about the contents of this document
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Table of Contents
Introduction -------------------------------------------------------------------------------------- 4
Canadian Electrical Code --------------------------------------------------------------------- 5
Electrical Code: Crossword------------------------------------------------------------------- 8
Manitoba Hydro---------------------------------------------------------------------------------- 9
Reading Blueprints ----------------------------------------------------------------------------- 9
Circuits------------------------------------------------------------------------------------------- 11
Electrical Tools -------------------------------------------------------------------------------- 12
Electrical Tools: Matching------------------------------------------------------------------- 15
Miscellaneous Electrical Terms ----------------------------------------------------------- 16
Electrical Terms: Crossword --------------------------------------------------------------- 18
Answer Key------------------------------------------------------------------------------------- 19
References ------------------------------------------------------------------------------------ 20
3
Introduction
As a student studying Electrical Applications, you will hear trade terminology everyday.
As a result, it is highly recommended that you become familiar with Electrical
terminology, before the start date of your program. This will ease some of the workload
required of you during the course.
This guide mainly focuses on the some of the basic terms used in residential wiring &
the Canadian Electrical Code. it does not include all the key words. Self-tests and
answer keys have been included in this guide. If you are scoring below 80% on the selftests, it is recommended that you go back and review those areas.
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Canadian Electrical Code
The Electrical Contractor must do all work “according to
Canadian Electrical Code”. (In Manitoba follow, “Manitoba
Electrical Code”1.) The first section of this booklet will
explain what electrical code is, and important terminology
relating to electrical code.
The Canadian
Electrical Code serves
as the basis for wiring
regulations across
Canada.
Canadian Electrical Code:
•
The Canadian Electrical Code (CE code) is a standard published by the
Canadian Standards Association (CSA) addressing: Electrical safety, shock,
and fire hazards of electrical products in Canada.
•
The first edition of the Canadian Electrical Code was published in 1927.
•
The current (20th) edition was produced in 2006.
•
Code revisions are now scheduled on a three-year cycle, so be sure
you are using the current code book!
•
The Code outlines in detail what wiring methods are acceptable and what
practices are not allowed.
•
In the current (20th) edition, the Code recognizes that other methods can be
used to assure safe installations, but these methods must be acceptable to
the authority enforcing the Code in a particular city or Province in Canada.
The Code is divided into sections, covering topics such as:
•
Conductors
•
service equipment
•
circuit loading factors
Make sure you are
familiar with the latest
Code requirements
before you begin wiring
1
You can find The Manitoba Electrical Code online at:
http://www.hydro.mb.ca/customer_services/permits_and_inspections/electrical/electrical_code_2006.pdf
5
•
grounding and bonding
•
wiring methods
•
protection
•
low-voltage power circuits
•
hazardous (dangerous) locations
•
installation of electrical equipment
•
Additional sections give rules for special areas such as wet locations,
patient care areas, emergency systems, temporary installations, and others.
The Canadian Electrical Code does not apply to vehicles, systems operated by an
electrical or communications utility, railway systems, aircraft or ships.
Key Terms
Bonding - Connecting wires (conductors).
Conductors - A substance that allows an electric current to pass
through it easily.
Circuit - a circuit is a path between two or more points along which an electrical current
can be carried.
Circuit loading factors - Criteria that does not allow you to go over the number of
receptacles on a circuit, gauge of wire, amperage of the circuit breaker.
Electrical equipment - receptacles (outlets), light fixtures, switches, conductors(wires),
circuit breakers, electrical panel, conduit, etc.
Grounding - The process of connecting equipment to a common ground or “earth”. This
is done as a safety mechanism in order to avoid the unsafe energizing of equipment.
6
Low-voltage power circuits - For example, thermostat wires, telephone wire,
co-axial cable.
Overload - Can be classified as an overcurrent which exceeds the normal full load
current of a circuit, Also characteristic of this type of overcurrent is that it does not leave
the normal current carrying path of the circuit, that is, it flows from the source, through
the conductors, through the load, back through the conductors, to the source again.
Protection - against shock and fire hazards.
Service equipment - Circuit breakers, fuses.
Wiring methods - For example, running power through the switch or receptacle.
7
Electrical Code Crossword
Directions: Find the words to the clues below. (Study pages 4-5 first, then without
looking back, complete the crossword.)
Across
5. serves as the basis for wiring regulations across Canada
Down
1. process of connecting equipment to earth
2. light fixtures, switches, conductors(wires), etc.
3. allows an electric current to pass through it
4. a path between two or more points along which an electrical current can
be carried.
8
Manitoba Hydro
Manitoba Hydro supplies power to residences and cottages
through overhead wires or underground cables. The service
supplied is a three-wire service, which is made up of two live
conductors and one neutral conductor. With the three-wire service, 120-volt, 120/240
volt and 240-volt capabilities are provided.
Key terms
Live Conductors - Conductors (wires) that have power running through them. The term
“hot” is often used to describe a wire that has power running through it.
Neutral conductor - The neutral conductor is the conductor connected to ground in
most existing power systems. However, this is not the definition of the neutral
conductor. The definition of the neutral conductor is the conductor that under balanced
load conditions will carry no current. In a three-phase system where each of the three
phases has an equal load, the current in the neutral conductor will be zero. In practice, it
is easiest to ground the neutral conductor.
Overhead wires - Wires that are above ground.
Underground cables - Wires that are buried under the ground.
Reading Blueprints
Blueprint - The documents used by contractors and builders that instruct them on how
to build. Each set of blue prints should include the following: floor plans; plans for the
foundation and information on footings and framing; front, side and rear elevations; a
roof plan; electrical layout and Kitchen cabinet layout; and construction details.
9
Electrical layouts - Electrical diagrams usually include a legend or key on the
page, which explains what each symbol represents. From this diagram the electrician
can determine the location of electrical outlets, fans, fixtures, light fixtures etc. Electrical
diagrams may also include legends for heating systems, door swings and sizes,
furniture placement, and may specify certain finishes.
Floor-plan - A floor plan is a simple line drawing showing rooms as if seen from above.
Walls, doorways, and windows are often drawn to scale. (Not as detailed as a
blueprint.)
Symbols used in an electrical floor plan.2
2
www.edrawsoft.com, retrieved on March 15, 2008
10
Sample Floor-Plan3
Circuits
What is a circuit? An electrical path between two points.
Circuit branch - A point in an electric circuit where current
can flow in more than one direction. A circuit branch
creates two branches from one main line carrying current.
3
www.floorplansplus.com
11
Circuit breakers are
now used in new
home construction.
Fuses were used up
to the late 1960’s.
That means that each circuit branch receives half of the current coming from
the main line. In other words, if you had a main line that carried 10 Amps of current, you
would have two circuit branches that each had five Amps.
Circuit breaker - A device designed to open under an abnormal amount of current flow.
The device is not damaged and may be used repeatedly. Rated by voltage, current, and
horsepower.
De-energized circuit - A circuit that has no power applied to it.
Arc-Fault Circuit interrupter (AFCI) - A circuit breaker designed to prevent fires by
detecting electrical arcs and disconnect power before the arc starts a fire.
Ground Fault Circuit Interrupter (GFCI) - A device that stops the flow of electricity by
opening or breaking the circuit when a flow of current to ground is detected. Electrical
outlets near water sources like sinks and laundry appliances, as well as all garage and
outdoor outlets, should have a ground fault circuit interrupter GFCI).
Electrical Panel - An insulated panel on which electrical wires are connected to circuit
breakers.
Electrical Tools
Most electrical wiring jobs are relatively easy to handle with a few inexpensive tools.
Circuit tester (Voltage tick) - Simple and inexpensive, a circuit
tester plugs into a conventional outlet and will tell you whether
the circuit is "hot" (charged) or whether it's properly grounded.
Continuity tester - A small, battery-operated continuity tester costs less than
$10. It can be used to determine whether wiring is broken and whether
electrical circuits are complete.
12
Lineman's pliers - A pair of these is the best tool to use for
cutting heavy wire or cable and twisting wire ends together. To
twist two wires together, hold them side by side with one hand,
their stripped ends aligned, and point the blunt end of the pliers in line with them, clamp
down, and twist in a clockwise direction.
Long-nose pliers - Long-nose pliers are great for bending
small loops at wire ends or for cutting off wires (most include a
wire-cutting section). Use the pointed end of the pliers to form
a smooth, 3/4-circle at a wire's end, designed to circle around
a screw terminal (always hook the wire onto the terminal with the end of the bend
sweeping clockwise from the wire).
Multi-meter - You'll want to have a multi-meter on hand for making a
variety of continuity checks, checking voltage, and other similar tasks.
Read the manufacturer's instructions for a thorough understanding of
techniques. Multi-meters, which do the job of ohm meters, volt meters,
and related tools, are sold at consumer electronics stores.
Neon voltage tester - This helpful little tool can tell you whether wires
are "hot" or not. When using it, be sure to hold only the insulated probes- not the bare parts. Touch one probe to what you suspect is a hot wire
and the other probe to a neutral wire or grounding wire (or grounded
metal electrical box). If the small light glows, the circuit is live.
Screwdrivers - You'll want an assortment of screwdrivers with insulated rubber grips.
Be sure to get both flat-bladed and Phillips-head drivers.
13
Wire stripper - Most electrical wires run inside a sleeve of
insulation, a plastic, rubber or paper coating that prevents bare
conductors from shorting against each other or shocking you.
When splicing wires(connecting two or more wires together) or
connecting them to devices, you must remove the insulation, a
relatively simple job when you have the right tool-- an inexpensive wire stripper.
The stripper should be set so that it cuts the insulation but doesn't nick the wire (or use
the slot that matches the wire conductor's size). Hold the wire with one hand, bite into
the insulation with the stripper, about 1/2 inch to 3/4 inch from the wire's end, rock the
stripper back and forth, and pull the insulation off the end of the wire.
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Matching: Electrical Tools
Directions: Write the correct name next to the tool on the right. (Answers on pg. 19)
1.
2.
3.
4.
5.
6.
7.
15
Miscellaneous electrical terms
Ampere - The measurement of intensity of rate of flow of electrons in an electrical
circuit. An ampere is the amount of current that will flow through a resistance of one
ohm under pressure of one volt.
Electrical Load - That part of the electrical system which actually uses the energy or
does the work required.
Ohm - The unit of measure for electric resistance. An ohm is the amount of resistance
that will allow one ampere to flow under a pressure of one volt..
Ohm's Law: The relationship between voltage, current and resistance, expressed by
the equation V=IR, where V is the voltage in volts, I is the current in amperes, and R is
the resistance in ohms.
Over current - A condition which exists on an electrical circuit when the normal load
current is exceeded. Over currents take on two separate characteristics - overloads and
short circuits.
Overload - Can be classified as an overcurrent which exceeds the normal full load
current of a circuit, Also characteristic of this type of overcurrent is that it does not leave
the normal current carrying path of the circuit.
Recessed lighting - Also known as “pot lights”.
Receptacle - Also known as an electrical outlet.
Retro-fit - Servicing old technology.
Resistive Load - An electrical load which is characteristic of not having any significant
inrush current. When a resistive load is energized, the current rises instantly to its
steady-state value, without first rising to a higher value.
16
Semiconductor Fuses - Fuses used to protect solid-state devices. (see High
Speed Fuses).
Short Circuit - Can be classified as an overcurrent which exceeds the normal full load
current of a circuit by a factor of many times (tens, hundreds or thousands greater). Also
characteristics of this type of overcurrent are that it leaves the normal current carrying
path of the circuit, (it takes a "shortcut" around the load and back to the source).
Short Circuit Rating - The maximum short circuit current an electrical component can
sustain without the occurrence of excessive damage when protected with an
overcurrent protective device.
Volt - The volt (symbolized V) is the Standard International (SI) unit of electric potential
or electromotive force.
Voltage Rating - The maximum open circuit voltage in which a fuse can be used, yet
safely interrupt an overcurrent, exceeding the voltage rating of a fuse impairs its ability
to clear an overload or short circuit safely.
17
Electrical Terms: Crossword
Across
4. The unit of measure for electric
resistance.
5. Recessed lighting.
7. The measurement of intensity of rate
of flow of electrons in an electrical
circuit.
8. Standard International unit of electric
potential or electromotive force.
11. diagrams can determine the
location of electrical outlets, fans.
Down
1. not having any significant inrush current
2. Also known as an electrical outlet.
3. exceeds the normal full load current of a circuit
4. V=IR
6. Servicing old technology.
9. simple line drawing showing rooms as if seen from above.
10. documents used by contractors and builders that instruct them on how to
build.
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Answer Key
Crossword (Page 8)
1. grounding
2. electrical equipment
3. conductors
4. circuit
5. Canadian Electrical Code
Matching (Page 15)
1. Circuit tester (Voltage tick)
2. Lineman’s pliers
3. Wire stripper
4. Neon voltage tester
5. Continuity tester
6. multi-meter
7. Long-nose pliers
Electrical Terms: Crossword (Page 18)
Across
Down
4. ohm
1. resistive load
5. potlights
2. receptacle
7. ampere
3. overload
8. volt
4. ohmslaw
11. electrical
6. Servicing old technology.
9. floor plan
10. blueprint
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References
Manitoba Hydro, Retrieved on April 20, 2008, from: www.hydro.mb.ca
Glossary of Terms, Retrieved on April 26, 2008, from: www.nangle.co.uk
How to Read Blueprints, Retrieved on April 26, 2008, from:
www.englandhouseplans.com
Updated: August 2008
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