Section 22 of the CE Code
-understanding of confusing requirements

• (a) hazardous areas in accordance with Section 18; and
• (b) corrosive liquids, vapours, or moisture in accordance with this Section.

• (a) all locations suitably cut off from a Category 2 location and not classified as a Category 1 location;
• (b) all locations not suitably cut off from a Category 2 location but with adequate continuous positive pressure ventilation; and
• (c) dry well locations below ground where adequate heating and adequate continuous positive pressure ventilation is installed”

In the previous article we reviewed the changes made to Sections 0, 2 & 4. This article will cover the changes made to Sections 6, 8, 10 & 12.
 
Section 6 – Services and service equipment
 
Rule 6-102 – Number of supply services permitted
 
In order to provide clarity, the wording “from the same system of any one supply authority” has been removed from Subrule (1).  The previous wording appeared to permit an installation to have two supply services of the same voltage provided they were supplied from different systems.
 
Rule 6-206 – Consumer’s service equipment location
 
A new Subrule (3) has been added which now permits the service disconnecting means to be placed on the outside of the building or on a pole.  This is indeed a major change to the CEC and should provide greater flexibility with regards to the location of the service disconnecting means for new and existing installations.
For example, it will now be possible to install a 4-gang meter mounting device and have the 4 service disconnecting means placed on the outside of the building or on a pole.  As noted in Subrule (3)(a) the service disconnecting means must be installed in an enclosure approved for the location such as a Type 3R or protected against the weather.
 
In addition, Subrule (3)(b) requires the service disconnecting means to be protected from mechanical damage if it is located less than 2m above ground.
 
Rule 6-300 – Installation of underground consumer’s service conductors
 
In order to provide a means for transitioning between conductors with different insulation temperature ratings, Item (b) has been added and now permits a splice to be made in single or multiple-conductor cable for service entrance use below ground.
 
Rule 6-302 – Installation of overhead consumer’s service conductors
 
Subrule (1)(f) has been revised to include copper-sheathed cable as an acceptable wiring method for an overhead consumer’s service.
 
Rule 6-310 – Use of joints in consumer’s service neutral conductors
 
Due to the adverse effects of open neutral connections, Rule 6-310 generally does not permit the use of splices in the neutral or identified conductor.  The Rule does, however provide exceptions to this requirement and now includes a new Subrule (3) permitting the neutral to be spliced where a cable transition is made to accommodate the requirements of Rule 4-006.
 
Section 8 – Circuit loading and demand factors
 
Rule 8-200 – Single dwellings
 
Due to the ever increasing cost of fuel, there has been a significant increase in the use of electric vehicles.  In fact, it is anticipated that 1 of every 20 vehicles on our roads will be electrically powered by the year 2020.  As a result of the rapid increase in the use of electric vehicles the CEC has introduced several new requirements.  For example, in order to ensure the ampacitiy of the service conductors for single dwellings is adequate for the vehicle charging equipment, a new Item (vi) has been added to Rule 8-200(1)(a) and requires any electric vehicle charging equipment loads to be added with a demand factor of 100%.
 
Figure 1 illustrates a typical single dwelling demand calculation which includes the load for an electric vehicle charger.
 
Figure 1

It should be noted that the requirement as to whether or not to install a receptacle for electric vehicle charging equipment is located in Rule 26-710(o).  This rule states that the receptacle is required only when mandated by the National Building Code of Canada.  Appendix “B” should be consulted for further information on this requirement.
 
Rule 8-202 – Apartment and similar buildings
 
Again, in order to ensure the service conductors are adequate for the electric vehicle charging loads, a new Item (d) was added to Rule 8-202(3).  The new Subrule requires any electric vehicle charging equipment loads not located in dwelling units to be added with a demand factor of 100%.  This new requirement could have a significant impact on the size of the main service equipment for apartments and similar buildings.
 
For example, if 20 of the car spaces in a 100 suite apartment complex are each equipped with a 6kW electric vehicle charger, the demand on the main service would be calculated at 20 suites x 6kW x 125% = 150kW.  The use of the 125% factor is a result of
Rule 86-302 which considers electric vehicle charging equipment loads to be continuous for the purposes of Rule 8-104.
 
Section 10 – Grounding and bonding
 
Rule 10-000  -  Scope
 
In order to provide clarity, the Scope of Section 10 has been revised significantly to clearly indicate that the Rules in this section cover the following requirements pertaining to:
 
1) bonding non-current carrying metal parts of electrical equipment and metal systems together with a connection to the grounded system conductor where present. 
 
2) grounding the electrical system and associated non-current carrying metal parts.
 
3) the use of ungrounded systems or systems incorporating neutral grounding devices.
 
Rule 10-002  - Object
 
In previous editions of the Code, the objectives of “grounding” and “bonding” were treated jointly, which in some cases led to confusion with interpretation and application of rules.  The 2012 CEC has been revised to provide a separate object for each of these terms as well as addressing the use of ungrounded systems or systems incorporating neutral grounding devices.
 
As noted, the object of bonding metal parts and metal systems together, and to the grounded system conductor, is basically to reduce the danger of electric shock or property damage by providing a low impedance path for fault current and to establish an equipotential plane to minimize the possibility of a potential difference between metal parts.
 
The object of grounding the electric system and non-current carrying metal parts is to connect the earth to the equipotential plane in order to minimize any potential difference to earth.  The new Code indicates the object of using an ungrounded system or a system incorporating a neutral grounding device is to limit the magnitude of fault current and minimize the damage resulting from a single fault.
 
Rule 10-106  -  Alternating current systems
 
In order to align editorially with the rest of the Code the term “ground detection” was revised to “ground fault detection”.
 
Rule 10-212  -  Grounding connections for equipment in an ungrounded system
 
The use of ungrounded systems or a system incorporating neutral grounding devices is not new, however the Code was silent on the grounding connections for these systems.
As a result, Rule 10-212 has been added to the Code and as noted in Subrule (1) requires there be no connection between the grounding conductor and the system neutral, where  one is present.  Subrule (2) requires the grounding conductor for the ungrounded system to connect the grounding electrode to the grounding terminal at the service box, or the equivalent where a service box is not installed.  A new note was added to Appendix “B” to provide further information on this requirement.
 
Rule 10-624  -  Bonding equipment to the grounded system conductor
 
Three new Subrules have been added to this Rule to identify the requirements pertaining to the bonding of equipment to the grounded system conductor. 
 
Subrule (1) indicates the connection between the metal enclosure of the service box, or equivalent equipment such as a transformer or generator, shall be made with a bonding screw or strap supplied with the equipment. 
 
As noted previously in Rule 10-002(1), one of the primary reasons for bonding metal parts together and connecting them to the grounded system conductor was to provide a low impedance path for the fault current back to the source.
 
In order to ensure field installed bonding jumpers are adequate for this purpose,
Subrule (2) was added and requires where a bonding screw or strap is not provided, a bonding jumper sized in accordance with Table 16 shall be used. 
 
For example, a 600A, 3-phase, 4-wire service is installed using a 600A main switch supplied with parallel runs of 350 kcmil, TW75 copper conductors.  The main switch is not equipped with a bonding screw or strap.  The size of copper bonding jumper required between the metal switch enclosure and the grounded conductor bus would be determined as follows:
 
Step 1) Use Table 2 to determine the ampacity of the service conductors.
            Table 2 → 350 kcmil → 75°C → 310A
                                       Parallel runs →     x 2
                                                                   620A
Step 2) Use Table 16 to determine the size of bonding conductor.
            Table 16 → Note: because the conductor ampacity exceeds 600A
                                          we must use 800A which requires a #1/0 copper
                                          bonding conductor.
 
The same process would be followed when determining the minimum size of bonding conductor required between a metal transformer enclosure and the grounded conductor bus or “X0” terminal.
 
For example, if a 75KVA dry-type transformer uses 300 kcmil, R90 XLPE conductors to supply a 225A, 120/208V, 3-phase, 4-wire panelboard, the bonding jumper would be determined as follows:
Step 1) Use Table 2 to determine the ampacity for the secondary conductors.
            Table 2 → 300 kcmil → 90°C → 320A
 
Step 2) Use Table 16 to determine the minimum size permitted for the bonding
            conductor.  As noted previously, because the conductor ampacity exceeds 300A
            we must use 400A, which requires a No.3 AWG copper bonding conductor.
 
A new Subrule 3 has been added to address situations where the enclosure of the service box or equivalent is not metal.  (For example, RPVC)  In these situations, the Code requires the bonding bus or terminal provided with the non-metallic enclosure to be interconnected with the grounded conductor bus in the same manner as the enclosure would be.  This would generally be accomplished by installing a bonding jumper sized in accordance with Table 16.
 
Rule 10-700  -  Grounding electrodes
 
As a result of the elimination of Table 17, Subrule 10-700(2)(a)(i) has been revised to indicate that when 2 rod electrodes are installed, they shall be bonded together with a grounding conductor sized in accordance with Rule 10-812 instead of Table 17.
 
This change removes a problem which existed in the previous Code where the grounding conductor from the rod electrode to the grounded conductor bus was permitted to be
No.6 AWG copper and the conductor between the two rod electrodes was required to be sized in accordance with Table 17, which in many cases resulted in a conductor size larger than No.6 AWG.
 
Rule 10-810  -  Grounding conductor size for DC circuits           
 
A new Subrule (2) has been added to address the requirements for determining the size of the grounding conductor for photovoltaic systems and renewable energy systems.  The Code now permits the grounding conductor for these systems to be sized in accordance with Rule 10-812.  As a result, a No.6 AWG copper conductor may be used.
 
Rule 10-812  -  Grounding conductor size for alternating current systems and for
                          service equipment
 
This is likely one of the most talked about changes to the Code.  Rule 10-812 has been revised to permit the size of the grounding conductor connected to a grounding electrode conforming to Rule 10-700 to be not smaller than No.6 AWG copper.  This change also led to the elimination of Table 17.
 
As explained in the Appendix “B” note for Rule 10-812, in a fault situation the majority of the fault current will follow the low impedance path provided by the grounded system conductor back to the source.  As a result, it has been determined that a grounding conductor sized not less than No.6 AWG is adequate to carry any portion of the fault current that will flow through it.
Rule 10-814  - Bonding conductor size
 
The wording “permitted to be” has been removed from Subrule (2) to remove any impression that a bonding conductor was not required to be paralleled.  In other words,
a bonding conductor is required in each parallel run
 
Section 12 – Wiring methods
 
Rule 12-012 – Underground installations
 
In order to harmonize with the CSA Standards for sand and gravel particulate sizing, Subrule (4) has been revised and now requires the screened sand used to bed direct buried conductors or cables to have a maximum particle size of 4.75 mm.  The previous Code permitted 6 mm.  A new note was added to Appendix “B” indicating the maximum
size of sand relates to the standard sieve sizes detailed in ASTM D2487.
 
Rule 12-102 – Insulated conductors
 
This rule identifies the requirements that pertain to the installation of insulated conductors when the ambient temperature is liable to become low enough to cause damage to the conductor insulation either during or after installation.
 
The rule originally applied to thermoplastic-insulated conductors only, however it has now been revised to include all insulation types.  A new note has been added in Appendix “B” to provide guidance on how to handle insulated conductors at low ambient temperatures.
 
Rule 12-108 – Conductors in parallel
 
Several changes have been made to this rule.  Subrule (1) has been revised to indicate that it applies to both ungrounded and grounded conductors.  In addition, the rule now refers to conductors that are paralleled together to form a single conductor as a set.
Subrule (1) also contains a new Item (e) which requires each parallel conductor set
to be comprised of conductors that are the same conductor material. 
 
A new Subrule 2 has been added to provide a means for complying with the equipment temperature ratings outlined in Rule 4-006.  As noted, Subrule (2) now permits a single splice for each conductor forming part of a parallel conductor set provided the splice is made to meet the requirements of Rule 4-006 and the conductors are spliced in the same manner.  In order to satisfy this requirement, approved devices of the same type would be required to splice each conductor of a parallel set.
 
Subrule (3) was added to indicate that in parallel sets, conductors of one phase, polarity or grounded circuit conductor need not have the same characteristics as those conductors of another phase, polarity or grounded circuit conductor. 
 
Rule 12-120 – Supporting of conductors
 
When armoured cables such as TECK90, AC90, ACWU90, etc. are installed in vertical runs, the weight of the internal cable assembly may cause excessive strain on conductor terminations.  In order to address this concern Subrule (4) has been added and requires
the internal assembly of cables such as TECK90, AC90, ACWU90, etc. to be supported at intervals not exceeding those specified in Table 21. 
 
Alternatively, as noted in items (a), (b) & (c) the internal cable assembly could also be supported by:
            - incorporating a bend or bends equivalent to a total of not less than 90° at
              intervals not exceeding the distances specified in Table 21.
 
            - installation of a horizontal run of the cable not less than the length of the
              vertical run.
 
            - use of cable that is specifically designed for vertical runs, such as Risertek 90
              cable, etc.
 
Rule 12-510 – Running of cables between boxes and fittings
 
In order to prevent damage to the outer covering on non-metallic sheathed cables, as well as the insulation on the conductors, Rule 12-510(3) and Rule 12-520 have been revised to prohibit fishing of non-metallic sheathed cables where metal sheeting or cladding, metal joists, metal top or bottom plates, or metal studs are used. 
 
Rule 12-600 – Armoured cable work Rules
 
Up until recently armoured cables were not permitted to be installed in raceways (other than situations where the raceway was being used to provide mechanical protection).
The 2012 CEC however, has been revised to permit the use of armoured cable in a raceway provided the installation complies with Rules 12-602(6), 12-614(3) and 12-902(2).
 
Rule 12-602 – Use
 
Subrule (6) was added to permit armoured cable for use in a raceway provided the armoured cable has an overall jacket and is installed in accordance with
Rule 12-902(2).
 
Rule 12-614 – Radii of bends in armoured cables
 
When armoured cables are pulled into a raceway, the armour and inner insulated conductors could be damaged as a result of the required increased pulling tension.  In order to address this concern Subrule (3) has been added to specify that where jacketed armoured cables are installed in raceways, the minimum bending radii measured at the innermost surface of the conduit or tubing shall not be less than:
           
            - 10.5 times the diameter for low-voltage cable
            - 18 times the diameter for high-voltage cable
            - those specified by the cable manufacturer
 
Rule 12-902 – Types of conductors and cables
 
The title and content of this rule have been revised to permit the use of jacketed armoured cables in raceways.  Subrule (2) specifies the requirements that must be satisfied as follows:
 
- Item (a) requires the installation not result in a greater conduit fill than that specified in Table 8.  For example, the minimum conduit size required for a 3-conductor jacketed TECK90 cable with copper conductors and a diameter of 50mm would be calculated as follows:
 
(Area = π r² = 3.1416 x 25² = 1963.5mm²)
Table 8 tells us that we can fill the conduit to 53%.
Table 9 indicates the minimum conduit size permitted would be 78mm or 3 in.
 
- Item (b) also requires that the installation complies with one of the following conditions:
 
            - Item (b)(i) requires that the length of cable pulled into the conduit does not         result in the calculated maximum pulling tension or the calculated maximum            sidewall bearing pressure being exceeded.  As noted in Appendix “B” this      information is available from cable manufacturers.
 
            - Alternatively, Item (b)(ii) requires the run of conduit between draw-in points       not have more than the equivalent of two 90° bends with a minimum bending          radius of not less than .944m for cable rated 1000V or less and 1.524m for cable       rated in excess of 1000V.
 
            - In addition, the length of conduit between draw-in points must not exceed:
                        -15 m for a three conductor copper cable
                        - 45 m for a single conductor copper cable
                        - 35 m for a three conductor aluminum cable
                        - 100 m for a single conductor aluminum cable
 
Using our previous example, if it was not possible to provide the information required by Item (b)(i) then the run of conduit between draw-in points could not have more than the equivalent of two 90° bends with a minimum bending radius of .944m and be restricted to a length of 15m.
 
A new note providing further information on these requirements has been added to Appendix “B”.
 
 Rule 12-1014 – Conductors in conduit
 
As a result of the introduction of RPV 90 and RPVU 90 cables for solar photovoltaic wiring, it was necessary to add Table 10B which provides the dimensions of PV cable for the purpose of calculating conduit and tubing fill.  Subrule (4)(d) has been revised to direct Code users to the new Table.
 
Rule 12-1308 – Supports
 
Up until now the Code has been silent regarding the support requirements for liquid-tight flexible conduit which in this regard has led to inconsistency and confusion.  In order to address this concern, Rule 12-1308 has been added to the Code and requires liquid-tight flexible conduit to be supported by straps or other devices within 300mm of every outlet box, junction box, or fitting and with spacing between supports of not more than 1.5m.
A new Subrule (2) which permits liquid-tight flexible conduit to be fished has also been included with Rule 12-1308.
 
Rule 12-2104 – Conductors in raceways
 
In order to provide clarity, Subrule (2) has been revised to indicate that each compartment of a divided wire-way may be treated separately when determining the maximum number of conductors and the interior cross-sectional area.
 
Rule 12-2200 – (Cable trays) Method of installation
 
In the previous Code, Subrule 12-2200(2) required that the maximum design and support spacing for cable trays not exceed the ratings specified by the manufacturer.  To assist installers with determining these requirements, Subrule (2) has been revised to require the maximum design load and associated support spacing not exceed the load/span ratings of the cable tray, which as noted in Appendix “B”, is required to be included with the marking on the cable tray.
 
Figure 1 is an example of the Part II product marking requirements for cable tray.
(Courtesy of Unitray Systems Inc.)



Cablebus – Rules 2250 to 2260
 
A new Subsection to address the installation requirements for cablebus has been added to Section 12.   Cablebus is defined in Section 0 as an assembly of insulated conductors with fittings and conductor terminations in a completely enclosed, ventilated, or non-ventilated protective metal housing.  The note for cablebus, located in Appendix “B”, indicates cablebus is normally assembled at the point of installation from the components furnished or specified by the manufacturer in accordance with the instructions for the specific installation.
 
Figure 2 illustrates a cross-sectional view of a cablebus assembly.
(Courtesy United Wire & Cable)

• use of cablebus
• methods of installation
• connection to other wiring methods
• provisions for bonding
• ampacities of conductors in cablebus

• the enclosure is approved to house these devices
• the wiring does not fill the wiring space at any cross-section to more than 75% of the cross-sectional area of the space