2012 Electrical Code Changes – Module 1

2012 Electrical Code
Changes – Module 1
Sections 0 - 4
ETEL-10(02)-00 (2012-03-26)
TableofContents
Section 0 – Definitions.................................................................................................................................................2 Section 2 – General Rules........................................................................................................................................5 Section 4 – Conductors...............................................................................................................................................7 ©
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2012 ELECTRICAL CODE CHANGES
Module 1
There have been numerous changes to the 2012 Canadian Electrical Code. The following
material only describes changes which may be considered as major. For complete Code
information, refer to the 2012 Canadian Electrical Code available at www.csa.ca.
Please note: minor electrical code changes are not covered in detail.
Section 0 – Definitions
Newton-metre
A newton-metre is a unit of torque (also called “moment”) in the SI system. One newtonmetre is equal to the torque resulting from a force of one newton applied perpendicularly to
a moment arm which is one metre long. This new term can be found in Tables D6 and D7
regarding the proper tightening of screws and lugs (torque).
Approved (as applied to electrical equipment)
Appendix B notes are summarized as follows:
 Electrical equipment installed under provisions of this Code is required to be certified to
the applicable CSA product standards.
 Where such CSA standards do not exist or are not applicable, it is additionally intended
by this definition that such electrical equipment be certified to other applicable standards
such as ULC standards.
 Equipment approval could be accomplished via a field evaluation procedure in
conformance with the CSA Model Code SPE 1000.
Samples of acceptable certification marks
For more information, download BCSA Information Bulletin B-E3 071019 3 Revision 1,
Approved Certification Marks for Electrical Products located at
www.safetyauthority.ca/regulations/electrical/information-bulletins
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Cablebus
Selection of the proper Cablebus system must be undertaken with care to assure that it
compliments the design of the overall electrical power system. Cablebus systems are fully
engineered with particular emphasis placed on cables, system balance, short circuit
capability, and grounding requirements. Each one of these key design considerations must
be analyzed separately to determine how they affect the overall system design.
Cablebus System Schematic
Ground Fault, Ground fault circuit interrupter (GFCI), Ground fault circuit interrupter
Class A (Class A GFCI), Ground fault detection, Ground fault protection (see
Appendix B notes)
Revisions have been made in the 2012 CEC Definitions to clarify these phrases:
Ground fault circuit interrupter is described to inform the reader of the generic nature of
the term and that more than one type and form of GFCI exists.
GFCI - Class A type is described further in the appendix B notes and the term is now used
throughout the Code when devices require such protection
Ground fault detection is described to clarify that these devices are not recognized as
providing ground fault protection
Ground fault protection is revised to alert users of the Code to refer to CSA C22.2
standards for each particular type of ground fault protection mandated by this Code.
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Grounding conductor
It is intended that the grounding conductor will terminate on the enclosure for the service
box or protective devices supplying the system in cases where the system is not grounded,
and at the internal bus for the grounded conductor where the system is grounded.
Note the grounding conductor connection is terminated on the neutral to comply with the
Appendix B note.
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Section 2 – General Rules
Rule 2-304 Disconnection
It is intended by this Rule that all electrical work shall be performed on equipment “in an
electrically safe condition”. CSA Z462 further indicates that electrical work may only be
performed when de-energizing introduces additional hazards or increased risks.
Appendix B and CSA Z462 provide examples when working de-energized is not ‘feasible”.
These circumstances include trouble shooting of control circuits, testing and diagnostics.
Other examples include interruption of life-support equipment, deactivation of emergency
alarm systems and shutdown of hazardous location ventilation equipment.
Working energized is the exception not the Rule!!
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Rule 2-310 Entrance to, and exit from, working space
This revision clarifies that it is the nameplate rating of the equipment which determines the
layout of the equipment room. If the layout in Subrule (2) is such that workers do not have
means of egress without passing the equipment, the requirements in Rule 2-308 shall be
increased to 1.5m.
Note that the equipment has a 1000A main breaker but the 1200A nameplate shall
determine the electrical room layout and clearance requirements. An acceptable layout in
compliance with Subrule (2) should be the priority and only when it is not possible should
the working space be increased to 1.5M.
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Rule 2-314 Receptacles required for maintenance of equipment
This is a new rule requiring ready access to a 120V / 20A receptacle for servicing HVAC
and similar type equipment.
See Rule 26-704 and Rule 26-704 Appendix B Note for more information.
Section 4 – Conductors
Rule 4-004 Ampacity of wires and cables (see Appendix B and I)
Subrule (1) (a) - The allowable ampacities of the smaller conductor sizes in Table 1 (free air
rated) have changed. Some of the larger sizes have also changed but not necessarily
increased.
Subrule (1) (b) - The ratings of Table 2 apply to 1, 2, or 3 conductors in a raceway or 2 or 3
conductor cable, except as indicated in (1) (d). Table 2 ampacities do not apply to
underground runs where the conductors are sized No. 1/0 or larger. The allowable
ampacities of the smaller conductor sizes listed in Table 2 have changed upwards. Some of
the larger sizes have changed but not necessarily upwards.
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See Rule
14-104(2)
The triple red asterisks indicate a BC amendment will be provided.
The following is the proposed amendment as a footnote:
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Subrule (1) (b) - With the new ampacities listed in Table 2, it is important to remember that
there are restrictions on the maximum overcurrent protection permitted for sizes #14, #12
and #10 copper and #12 and #10 aluminum. These restrictions are made in new Subrule
14-104 (2).
Rule 14-104 (2) has been added to restrict the allowable overcurrent protection of sizes
#14, #12 and #10 copper to 15 A, 20 A and 30 A respectively. #12 aluminum is restricted to
15 A, #10 aluminum is restricted to 25 A by way of a Feb 6th errata from CSA.
This Subrule and the restriction have been added to ensure that Users of the Code
understand the new ampacity tables and the required protection as well as provide
minimum safety requirements when these common conductor sizes are used. The
reference to Subrule (1) (c) “as provided by other Rules of the Code” refers to Rules which
specifically permit sizes # 14, # 12 and #10 conductors to have O/C protection greater than
the protection required by items (a), (b), and (c). Rules regarding the protection of
conductors supplying capacitors, transformers, motors, arc welders, and similar equipment
would qualify under this provision.
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Subrule (1) (d) – This rule has been reworded. The reference to calculating ampacities
based on IEEE 835 has been deleted and the new wording directs the User to the
installation configurations in Appendix B and the ampacity tables found in Diagrams D8A –
D15B.
The new wording clarifies the installation must be installed in accordance with Diagrams
B4-1 to B4-4 in order to use the ampacities listed in Tables D8A through D15B. Installations
that do not comply with these Diagrams (i.e. different depth, configurations, number of
parallel sets, etc.) shall be calculated according to item (e).
The illustrations in Diagram B4-4 now include 8 parallel runs of raceway (conduit).
Subrule (1) (e) - Where underground installations do not comply with Appendix B diagrams,
IEEE 835 ampacity calculations shall be performed by a P.Eng and submitted to the AHJ
with the plans and specifications.
Subrule (1) (f) - Where underground installations consist of conductor sizes smaller than
N0. 1/0 AWG, installers may use the ampacities listed in Table 2 (copper conductors in
raceway or cable), OR where other ampacities are desired, contractors shall provide IEEE
835 ampacity calculations performed by a P.Eng to the AHJ with the plans and
specifications.
Rule 4-004 (2) – Similar changes have been made to items (2) (a), (b), (c), (d), (e) and (f)
as above.
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See Rule
14-104
and errata
The triple red asterisks indicate a BC amendment will be provided
The following is the proposed footnote as amendment:
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Subrule (8) - This subrule has not been revised but Table 5A which it refers to has. New
temperature rows have been added and new de-rating factors used.
When required to de-rate for ambient temperatures, use of a 900 C conductor has the
advantage of allowing the initial ampacity used in a de-rating calculation to be based on its
corresponding 90 C ampacity. Remember that the final calculated ampacity is always
limited to the corresponding ampacity in the column which matches the equipment
termination temperature rating.
Subrule (9) - This new Subrule addresses installations where a “free air rating” may be
applied to single conductors not installed in cabletray. The wording is similar to that found
in Rule 12-2210 (2). Comparison calculations using 4-004(9) and 12-2210(2) will now result
in the same answer.
Subrule (10) - This Subrule has revised wording, “in contact with” has been replaced with
“are spaced less than 25% of the diameter of the largest conductor or cable”.
Note: A BC Amendment has been proposed to change the reference of Subrule 1(b) or 2(b)
to Subrule 1(a) or 2(a).
Subrule (11) - In the 2009 Code this was Subrule 4-004 (10). While the numbering has
changed, the wording and intent of this Subrule has not changed. The reference to Rule
4-010(3) will likely be changed to Rule 4-010 (7).
Subrule (12) - This Subrule has revised wording, “in contact with” has been replaced with
“are spaced less than 25% of the diameter of the largest conductor or cable”. Similar
wording is used in Rule 12-2210 (3), regarding ampacity calculations for conductors in
cable trays.
Subrule (13) - In the 2009 Code, Subrule 4-004 (11) stated “ Where multi-conductor cables
are run in contact with each other for distances exceeding 600mm, the ampacity of the
conductors shall be corrected by applying the factors in Table 5C”. This Subrule does not
appear in the 2012 Code so the reference to Subrule 12 is not necessary. Until Resolved Status Quo should continue to be used. I.e. continue to derate multi-conductor cables when
run in contact with each other and the distances exceed 600mm.
Subrule (21) - Appendix B Note to Rule 4-004(21): A covered conductor is a conductor
encased within material of composition or thickness that is not recognized by this Code as
electrical insulation. Covered conductors should always be treated as bare conductors for
working clearances because they are considered uninsulated conductors.
The NEC has a similar definition. “Covered Conductor” - A conductor enclosed within a
material of composition or thickness not defined as electrical insulation.
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This type of conductor is not “touch-safe” and is used to provide an additional level of
protection against contact with tree branches (nuisance tripping of O/C and shock hazard).
See Table 66 for more information.
Rule 4-006 Temperature limitations (see Appendix B)
It is intended by this Rule that the ampacity of conductors is selected from the temperature
column in Table 1, 2, 3, or 4 which corresponds to the temperature rating marked on the
electrical equipment.
Subrule (1) - CSA and UL testing is performed using 75 C conductors and the equipment is
approved as a system (equipment and conductor). The use of conductors with higher
temperature ratings is acceptable provided the ampacity is determined from the column
which corresponds to the label on the breaker.
Using a conductor with a 90 C temperature rating with a 90 C ampacity may cause
nuisance tripping or overheating of the device and conductor.
Using a conductor with a 60 C temperature rating where a 75 C insulation rating is called
for, may overheat the conductor and cause it’s insulation to fail.
As an example where a conductor is terminated on a breaker with a 75 °C rating, the
maximum conductor ampacity would be based on the 75 °C column of the Tables.
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All devices connected are to be
checked for temperature ratings
both dryer and range receptacles
are rated for 750C
Most overcurrent devices are
rated either 60/750C or 750C
Panel boards, combination
panels are typical rated
60/750C –always check
specification labels
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Subrule (2) – Some equipment does not have temperature termination ratings marked on
the equipment or the equipment may have lugs only, such as a splitter, which are typically
marked for 90 C. In these cases, it is acceptable to give the equipment a 90 C termination
rating.
Remember that a conductor has two ends and that the termination on each end must be
considered when applying the sizing rules. For example, consider a conductor wired to a 75
°C termination on a circuit breaker at one end, and a 60 °C termination on a receptacle at
the other end. This circuit must be wired with a conductor that has an insulation rating of at
least 75 °C (due to the circuit breaker) but must be sized based on the ampacity of 60 °C
(due to the receptacle).
Notes
No distribution or utilization equipment rated under 600V is listed and marked for the use of
90°C wire at its 90°C ampacity. This includes distribution equipment, wiring devices,
transformers, motor control devices and even utilization equipment such as HVAC, motors
and light fixtures.
Some equipment requires the conductors that are terminated in the equipment to have an
insulation rating of 90°C but an ampacity based on 60 or 75°C. This equipment might
include 100 percent-rated circuit breakers, fluorescent lighting fixtures, etc., and is marked
to indicate such a requirement.
Some motors require conductors with high insulation ratings (Rule 28-104) but their
ampacity is based on 75 C columns in Table 2 or 4 (Rule 28-104 (1)).
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In this example, both 75 C and 90 C are used but the ampacity of both
conductors must be based on 75 C due to the breaker markings.
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Termination ratings, conductor temperature ratings and ampacity derating
Conductors with temperature ratings higher than the temperature termination ratings of the
equipment they are connected to are permitted to be used provided derating factors are
applied and subject to the following,
1) The ampacity value determined after applying the derating factors must be equal to or
less than the ampacity of the conductor if it was based on the temperature limitations at its
terminations (e.g. equipment was marked 75C)
2) The derated ampacity becomes the allowable ampacity of the conductor, and the
conductor must be protected against overcurrent in accordance with this allowable
ampacity.
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Remember, when derating is performed using 90 C conductors, the calculated ampacity
must be large enough for the load AND be equal to or less than the given ampacity in the
column corresponding with the temperature termination rating of the equipment (switch or
C/B) involved, otherwise the temperature of the conductor may exceed the temperature
rating of the termination.
The maximum over current protection of #12 is 20 A (see Rule 14-104 (2)), regardless of
the calculated ampacity of the conductor. Similar restrictions in Rule 14-104 (2) are in place
for #14 AWG and #10 AWG copper and #12 AWG and #10 aluminum (by CSA errata).
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Note: 60 C rated conductors cannot be used as equipment rated above 100 A doesn’t have
a 60 C temperature rating.
Rule 4-008 Insulated conductors (See Appendix B)
In selecting a conductor, cable, flexible cord, equipment wire or portable power cable, it is
important that:
• It is designed for the specific application and conditions of intended use.
• The approval is conditional on those products being installed and used within the design
parameters for which they were manufactured and certified.
• Consult with the appropriate Table (11 or 19) and with the cable manufacturer to ensure
that the proper conductor, cable, flexible cord, equipment wire or portable power cable is
selected for the specific application.
Rule 4-010 Induced voltages and currents in metal armour or sheath of single
conductor cables (See Appendix B)
This Rule has been revised and updated. Requirements from other Rules in the Code
(12-3022) have been consolidated under this heading. See Appendix B notes.
Rule 4-012 Uses of flexible cord (See Appendix B)
The wording in Subrule (1) has been revised to clarify that selection of an approved flexible
cord must also include ensuring it is suitable for the intended location and application in
respect to the listed subjects. This is one of the most common revisions in the 2012 Code.
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Rule 4-020 Equipment wire (See Appendix B)
Similar to Rule 4-012, the wording in Subrule (1) has been revised to clarify to the user that
selection of an approved flexible cord must also include ensuring it is suitable for the
intended location and application.
Rule 4-024 Size of neutral conductor (See Appendix B)
The previous limitation on reducing neutrals has been expanded to include “non-linear
loads” supplied from a 3ø 4 wire system. Appendix B notes provide examples of non-linear
loads. Examples of non linear loads include dimmers, computers, microprocessors and
most other electronic loads.
Rule 4-036 Use of identified conductors
Subrules (1) – (3) have been revised to include “copper-sheathed cable”. Throughout
numerous rules in the new Code, references to “copper-sheathed cable” have been added
as an acceptable wiring method.
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Rule 4-040 Uses of portable power cable (See Appendix B)
The wording in Subrule (1) has been revised to clarify to the user that selection of an
approved flexible cord must also include ensuring it is suitable for the intended location and
application.
New Subrule (4) recognizes Type DLO cable as acceptable for use in sizes 1/0 and larger
when run in cable tray.
New Table 12E shall be used to determine the ampacity of Type DLO.
DLO Cable Description
DLO is especially suitable to supply power to traction motors of diesel-electric locomotives.
It is also recommended as a portable cable for drilling rigs, on-shore or off-shore, railroad
and transit car wiring, electric earth-moving equipment, in shipyard applications, arc welder
supply leads, power and control jumper cable, Telcom power supply and motor leads. The
cable is suitable for use in wet or dry areas, conduit, ducts, troughs or trays, and where
superior electrical properties are desired. The maximum continuous conductor temperature
for normal operation in wet or dry locations is 90°C. DLO resists oils, acids, alkalies, heat,
flame, and has abrasion resistance.
– Description courtesy of Nassau National Cable
Rule 4-042 Ampacity of portable power cable
Rule 4-042 contains the requirements for the allowable ampacity of portable power cables.
New Subrule (2) recognizes Type DLO cable as acceptable for use as fixed wiring in cable
tray in sizes 1/0 and larger. The ampacity shall be determined by using Table 12E and Rule
12-2210.
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