Guide to the Canadian Electrical Code, Part 1 , 25th Edition– A Road Map: Section 64

June 10, 2022

By William (Bill) Burr^[i]

The Code is a comprehensive document. Sometimes it can seem quite daunting to find the information you need quickly. This series of articles provides a guide to help users find their way through this critical document. It is not the intent of these articles to replace the notes in Appendix B or the explanations of individual requirements contained in the CEC Handbook**but hopefully provide help to navigate the Code.

Section 64 — Renewable Energy Systems, Energy Production Systems, and Energy Storage Systems

Rule 64-000 notes that this is a supplementary or amendatory section of the Code and applies to the installation of renewable energy systems, energy production systems, and energy storage systems except where the voltage and current are limited to Class 2 circuits as per Rule 16-200 1) a) and b).

Rule 64- 002 contains definitions of Special Terminology used in this Section. It is essential to understand these terms when reviewing the code rules of this Section. In addition, Appendix B contains many diagrams and explanations to help in understanding this terminology. For additional information, see CAN/CSA-C22.2 No. 257.

The Section contains 10 parts – General, Inverters, Solar photovoltaic systems, Small wind systems, Large wind systems, Micro-hydropower systems, Hydrokinetic power systems, Stationary fuel cell systems, Installation of batteries, and Energy storage systems.

General

The General requirements, Rules 64-050 to 64-078, apply to all Renewable Energy Systems and Energy storage installations and provide the minimum installation requirements applicable to all types of renewable energy systems covered in this Section.

Rule 64-050 allows renewable energy and energy system wiring to supply a building or structure in addition to other supply systems.

Rule 64-052 requires insulated conductors of renewable systems to be separated from other systems as per Rules 12-904 2) and 12-3030.

Rule 64-054 specifies that the ampacity of the common return conductor for a system with multiple supply circuit voltages must be not less than the ampere ratings of the individual supply circuits.

Rule 64-056 provided requirements for the installation of bipolar systems, including

• physical separation of monopoles where the sum of the monopole voltages exceeds the rating of the conductors or equipment,
• location of disconnects,
• routing of insulated conductors, and
• warning marking against disconnection of any grounded conductor.

Rule 64-058 outlines the installation of overcurrent protection devices, including selection, marking, location and connection, as per Section 26.

Rule 64-060 requires the installation of disconnecting means to disconnect simultaneously all ungrounded insulated conductors of all sources that are not solidly grounded and supplied from a renewable energy system and from all other insulated conductors in a building or other structure and batteries, including provision for, selection, marking, warning labels, location, connection, as per Rules 14-402, 14-414, 14-700, and 84-024, the capability of locking in the open position, and specific requirements for combiners and recombiners.

Rule 64-062 specifies that wiring methods be contained in metallic raceways, metal enclosures, or metal armoured or sheathed cables from the entrance to the building to the first readily accessible disconnecting means, except as required by Rule 64-210.

Rule 64-064 contains requirements for system grounding. Inverters used in renewable energy power systems usually contain a transformer that isolates the dc grounded circuit conductor from the ac grounded circuit conductor. This isolation necessitates the installation of both a dc and ac grounding system. The two grounding systems are bonded together or have a common grounding electrode so that all ac and dc grounded circuit conductors and equipment have the same near-zero potential to earth. The

interconnected battery cells are considered grounded where energy storage and renewable energy systems are installed. When a renewable energy dc supply system is equipped with a ground fault protection device, the required grounded conductor can be connected to the ground via the ground fault protection device. An external connection does not duplicate connections internal to the ground fault equipment. This Rule includes:

• subject to Rule 84-028, and except for 2-wire photovoltaic source and output circuits, renewable energy dc supply circuits, one conductor of a 2-wire system or the reference (centre tap) conductor of a bipolar system must be grounded per Section 10,
• 2-wire photovoltaic source and output circuits may be functionally grounded
• the dc supply circuits referred to above must be provided with a ground fault protection device or system that
  • detects a ground fault,
  • indicates that a ground fault has occurred; and
  • controls the faulted circuit by automatically disconnecting all conductors of the dc supply circuit or the faulted portion of the dc supply circuit, or
  • automatically causes the inverter or charge controller connected to the faulted circuit to cease supplying power to the output circuits and interrupts the faulted photovoltaic system dc circuits from the ground reference,
  • the location and connection of the grounding point on the renewable energy supply circuit must be as close as practicable to the supply source,
• permits the connection of the grounding conductor of a dc supply system, equipped with a ground fault protection device, to the grounding electrode via the ground fault protection device, but not externally duplicated if internal to the equipment.
• the dc circuit grounding connection must be made at any single point on the renewable energy supply circuit and must be located as close as practicable to the supply source,
• a renewable energy dc supply system equipped with a ground fault protection device may have the grounding conductor connected to the grounding electrode via the ground fault protection device,
• where the connection permitted as above is internal to the equipment equipped with a ground fault protection device, it must not be duplicated by an external connection,
• systems that are not solidly grounded must bear a warning stating that a shock hazard can be present when a ground fault exists in the system,
• equipment providing ground-fault protection mounted in locations that are not readily accessible must provide remote indication of ground faults,
• the remote indication required above must be
  • clearly labelled as to its purpose,
  • annunciate the status of the system to persons monitoring it, and
  • continue signalling until the condition has been corrected.
• Solidly grounded renewable energy dc supply systems must be connected to a grounding electrode by means of a grounding conductor according to Rule 64-068.

Rule 64-066 provides requirements for permitting ungrounded renewable energy power systems, including:

• providing overcurrent protection for all source and supply circuit insulated conductors with the exceptions contained in Rule 64-214,
• conspicuous, legible, and permanent warning labelling at each junction box and a suitable disconnecting means where the ungrounded circuits can be exposed during service,
• suitability of inverters or charge controllers for this use,
• provision of a ground fault protection device or system that detects, indicates, and interrupts a ground fault by disconnecting the dc circuit, the inverter, or the charge controller supplying the faulted circuit, or
• use with ungrounded battery systems that comply with Rule 64-800,
• the disconnecting means required by this Rule must not be connected in any solidly grounded conductor if the operation of that disconnecting means would cause the grounded conductor to be in an ungrounded and energized state.

Rule 64-068 outlines requirements for the installation of grounding electrodes and conductors for AC and DC renewable energy power systems required to be grounded and includes:

• connection of ac and dc grounding conductors to a single electrode, with separate grounding conductors, sized as required by Rules 10-114,
• connection of the dc grounding conductor between the identified dc grounding point and a separate dc electrode, and by bonding the dc grounding electrode to the ac grounding electrode as per Rule 10-104 b), or
• installing a combined dc grounding conductor and ac equipment bonding conductor as per Rule 10-116 and sized as per Rules 10-114 or 10-616 (choose the larger) (diagrams in Appendix B outline these methods).

Rule 64-070 requires the equipment bonding connection between exposed conductors surfaces and the renewable energy source or supply equipment following Section 10.

Rule 64-072 specifies marking all interactive system(s) points of interconnection with other sources with the rated ac operating voltage and current be provided at the disconnecting means for each interconnecting power source.

Rule 64-074 contains the requirements for warning notices and diagrams and outlines providing conspicuous, legible, and permanent warning notices, directories, and diagrams:

• on a building or structure to mark that it contains a stand alone electrical power system, and the location of the disconnecting means,
• on or near each disconnecting means, indicating the location of all other service boxes supplying power to the building, as per Rule 6-102 3), where the building or structure contains both a utility supply service and a renewable energy system, and it is not practical to group the disconnecting means as per Rule 6-102 2),
• at each service equipment location and the supply authority meter location, and
• at the location of the service disconnecting means of the premises that contains a renewable energy power system that stores electrical energy.

Rule 64-076 provides requirements for the interconnection to other circuits. It specifies that switching equipment controlling a renewable energy system, not intended to be interconnected with a supply authority, be constructed or arranged to render it impossible to switch on one source before the other has been disconnected.

Rule 64-078 requires that on the loss of interactive power:

• an interactive renewable energy system be provided with a means of detecting when the electrical production and distribution network has de-energized, and
• prevents the feeding of renewable energy into the other supply system until the normal voltage and frequency have been restored,
• the renewable energy system may continue to operate as a stand-alone system supplying loads that have been disconnected from the other supply system.

(Note: Appendix B has additional information on the general requirements rules.)

Inverters

Rule 64-100 outlines maximum circuit loading, including:

• the maximum current of the inverter output circuit is the inverter continuous output current rating,
• the maximum current of a stand-alone inverter input circuit is the stand-alone continuous inverter input current rating when the inverter is producing rated power at the lowest input voltage, and
• renewable energy system maximum current ratings are based on continuous

Rule 64-102 outlines requirements for Stand-alone systems and specifies that they comply with the applicable Rules of the Code with the following exceptions:

• the ac inverter output may supply ac power to the building or structure, disconnecting means at current levels below the rating of that disconnecting means, provided that the inverter output rating is equal to or greater than the connected load of the largest single utilization equipment connected to the system.
• The circuit conductors between the inverter output and the building or structure disconnecting means must be sized based on the output rating of the inverter and provided with overcurrent protection located at the output of the inverter per Section 14, and
• the inverter output may supply 120 V to single-phase, 3-wire, 120/240 V service equipment or distribution panels, provided that:
  • there are no 240 V loads,
  • there are no multi-wire branch circuits,
  • the rating of the overcurrent device connected to inverter output does not exceed the rating of the neutral bus in the service equipment, and
  • the equipment is conspicuous, legible, and permanently marked, with a warning not to connect it to multi-wire branch circuits.

Rule 64-104 specifies that interactive inverters mounted in locations that are not readily accessible may be mounted on roofs or other not readily accessible exterior areas provided that:

• a dc and ac disconnecting means is provided per Rule 64-060,
• an additional ac disconnecting means for the inverter is provided as per Rule 84-020, and
• a diagram is installed following Rule 84-030.

Rule 64-106 requires that only inverters and ac modules marked as interactive may have a connection to other sources in interactive systems.

Rule 64-108 stipulates that

• the inverter output rating and the maximum load connected between the neutral and any one ungrounded conductor must not exceed the ampacity of the neutral conductor, where an inverter with a single-phase, 2-wire output is connected to the neutral and only one ungrounded conductor, a single-phase, 3-wire system; or a three-phase, 4-wire wye-connected system, and
• a conductor used solely for instrumentation, voltage detection, or phase detection, and connected to a single-phase or three-phase interactive inverter, must be sized at less than the ampacity of the other current-carrying conductors but in no case smaller than the bonding conductor required by Rule 10-616.

Rule 64-110 addresses unbalanced interconnections and requires that:

• Single-phase inverters for renewable energy systems and ac modules in interactive renewable energy systems must not be connected to three-phase systems unless the interactive system is designed such that under normal operating conditions, the resulting three-phase system voltages are balanced within the limits of supply authority requirements, and comply with Rules 84-008 and 84-018, and
• Three-phase inverters and three-phase ac modules in interactive systems must have all phases automatically de-energized upon loss of the system voltage in one or more phases.

Rule 64-112 provides requirements for the interactive point of connection

• The output of an interactive inverter or power conditioning unit must be connected to the supply authority system as per Section 84 to protect against back feeds into a supply authority system fault.
• The output of an interactive inverter described in this Section must be connected to the supply side of the service disconnecting means, except the output may be connected to the load side of the service disconnecting means of the other source or sources at any distribution equipment on the premises provided that:
  • where distribution equipment such as switchboards or panelboards located on the premises is supplied simultaneously by a primary power source and one or more interactive inverters, and
  • where the distribution equipment connected is capable of providing multiple branch circuits or feeders, or both, the provisions for interconnection between the primary power supply source and the interactive inverter or inverters must comply with the following conditions:
    • each source interconnection must be made at a dedicated circuit breaker or fusible disconnect,
    • each panelboard, busbar, or conductor supplied by the multiple sources in the interactive system must be provided with:
      • suitable warning signs adjacent to each source disconnect to indicate that all of the disconnects must be opened to ensure complete de-energization of the equipment per Rule 14-414,
      • the point of connection must be positioned at the opposite (load) end from the input feeder location or main circuit location, where the panelboard is rated less than the sum of the ampere ratings of all overcurrent devices in source circuits supplying the panelboard, and
      • a permanent warning label at the distribution equipment to indicate that the overcurrent device must not be relocated.
    • Notwithstanding Section 14, the sum of the ampere ratings of the overcurrent devices in source circuits supplying power to a busbar or conductor may exceed the busbar or conductor rating to a maximum of 120% of the rating of the busbar or conductor.
    • Notwithstanding Section 14, for a dwelling unit, the sum of the ampere ratings of the overcurrent devices in source circuits supplying power to a busbar or conductor may exceed the busbar or conductor rating to a maximum of 125% of the rating of the busbar or conductor,
    • Notwithstanding the above, the sum of the ampere rating of the overcurrent devices may exceed the rating of the busbar or conductor, where means are provided to limit the input and output current of the interconnected systems to ensure the busbar or conductor cannot be overloaded.
    • The interconnection point must be made on the line side of all ground-fault protection equipment, except the interconnection point may be made on the load side of ground fault protection equipment, provided that there is ground-fault protection for equipment from all ground-fault current sources, and
    • ground fault protection devices used with supplies connected to the load side terminals are suitable for back-feeding.

Solar photovoltaic systems

Rule 64-200 provides additional marking requirements given in Rule 64-072 and specifies that:

• a permanent marking be provided at an accessible location at the disconnecting means for the photovoltaic output circuit, specifying the rated operating current and voltage, the maximum photovoltaic source circuit voltage calculated in accordance with Rule 64-202 and the rated short-circuit current,
• a photovoltaic system with rapid shutdown as per Rule 64-218 be provided with a permanent marking in an accessible location at the disconnecting means for the photovoltaic output circuit stating that the photovoltaic system is equipped with rapid shutdown, and
• a warning sign for a photovoltaic system in capital letters with a minimum height of 9.5 mm, in white on a red background.

Rule 64-202 provides requirements for voltage of solar photovoltaic systems and specifies:

• The maximum photovoltaic source and output circuit voltage are:
  • the rated open-circuit voltage of the photovoltaic power source multiplied by 125%, or
  • the maximum photovoltaic source and output circuit voltage may be calculated using the rated open-circuit voltage of the photovoltaic power source, the difference between 25 °C and the lowest expected daily minimum temperature, and the voltage temperature coefficient as specified by the manufacturer.
• The maximum photovoltaic source and output circuit voltage must be used to determine the voltage ratings of insulated conductors, cables, disconnects, overcurrent protection, and other equipment in photovoltaic source or output circuits.
• Photovoltaic source and output circuits installed in or on dwelling units may have a voltage not exceeding 600 V dc between any two conductors and between any conductor and ground, provided that:
  • all energized parts in the photovoltaic source and output circuits over 150 volts-to-ground are accessible only to qualified persons; and
  • the insulated conductors for photovoltaic source and output circuits over 30 V located inside the building are contained in metallic raceways, metal enclosures, or cables with a metal armour or metal sheath.

Rule 64-204 provides limits for voltage drop and specifies that notwithstanding the requirements of Rule 8-102, photovoltaic output circuit and photovoltaic source

circuit conductors meet one of the following requirements:

• the voltage drop must be considered acceptable where the conductors are rated not less than 125% of the maximum available short-circuit current of the solar photovoltaic system,
• the voltage drop must not exceed 5% of the rated operating voltage,
• the rated operating voltage drop must not exceed the percentage calculated by multiplying 50% of the rated current of the photovoltaic source circuit under consideration divided by the rated current of the entire array connected to the power conditioning unit or directly connected loads, or
• the resistance must be sufficiently low to facilitate the operation of the overcurrent device protecting the circuit in the event of a short-circuit.

Rule 64-206 provides the ampere rating of photovoltaic source and output circuits and requires the ampere rating of a photovoltaic source, and output circuit be

• the ampere rating of the overcurrent device protecting the circuit or
• the ampacity of the conductors, whichever is less, and
• not less than 125% of the rated short-circuit current of that photovoltaic source’s circuit.

Rule 64-208 outlines the photovoltaic module application class use and requires that:

• Photovoltaic modules marked with application Class A or C must be permitted to be installed in a location accessible to the public, and
• Photovoltaic modules marked with an application Class B must not be permitted for installations accessible to the public.

Rule 64-210 provides the wiring method for solar photovoltaic systems and includes:

• Notwithstanding Rule 12-102 3), flexible cords suitable for extra-hard usage may be used for the interconnection of photovoltaic modules within an array.
• Notwithstanding Rule 12-202, cables included as part of photovoltaic modules are permitted for the interconnection of photovoltaic modules within an array, provided that
  • the photovoltaic source and output circuits operate at a maximum system voltage of 30 V or less, or
  • greater than 30 V where the array is not installed in readily accessible locations.
• Notwithstanding Rule 12-202, Type RPVU cables are permitted for the interconnection of photovoltaic modules within an array, provided that the installation is serviced only by qualified persons and the installation is inaccessible to the public.
• Insulated conductors and cables installed in accordance with the above must be adequately protected against mechanical damage during and after installation and supported by straps or other devices located within 300 mm of every box or connector and at intervals of not more than 1 m throughout the run.
• Where the dc arc-fault protection referred to in Rule 64-216 is not located at the module, photovoltaic source circuit insulated conductors and cables installed on or above a building and installed following the above rules are to be provided with mechanical protection in the form of an enclosed raceway or other acceptable material to protect against damage from rodents.
• Notwithstanding Rule 12-2202, Type RPVU cables may be installed in a cable tray for the interconnection of the solar photovoltaic system.
• Type RPV conductors installed in a raceway are permitted for the interconnection of the solar photovoltaic system.
• Cables used for solar photovoltaic installations on or above a building must meet the flame spread requirements of the National Building Code of Canada or local building legislation.
• Type RPV insulated conductors and Type RPVU cables installed inside a building or structure must be contained in a raceway.
• Notwithstanding Rules 12-904 and 12-3030, junction boxes, enclosures, fittings, and raceways or compartments of multiple-channel raceways are permitted to contain insulated conductors of a single renewable energy system that are connected to different sources of voltage where:
  • all conductors are insulated for at least the same voltage as that of the circuit having the highest voltage; and
  • a suitable warning notice is placed at each enclosure and junction box giving access to the insulated conductors, indicating where multiple photovoltaic source circuits and photovoltaic output circuits are available within the junction boxes, enclosures, and raceways or compartments of a multiple-channel raceway.

Rule 64-212 provides the insulated conductor marking or colour coding specifications and includes:

• Notwithstanding Rule 4-032, dc photovoltaic output circuit insulated conductors, and photovoltaic source circuit insulated conductors installed between a module and the power conditioning unit of the dc system, must be coloured or coded, or both, as follows:
  • for a 2-wire circuit, red for positive and black for negative, or black insulated conductors manufactured with permanent surface printing indicating the polarity on the insulated conductor; and
  • for a 3-wire circuit (bipolar circuit), white or white with a coloured stripe for the mid-wire (identified as the centre tap), red for positive, black for negative, or black insulated conductors manufactured with permanent surface printing indicating the polarity on the conductor insulation.
• The requirements above must not be met by field marking or labelling.
• Notwithstanding the above, insulated conductor colour coding for multi-conductor cables is permitted to be made through suitable field labelling or marking permanently.
• The insulated conductor labelling and marking permitted must:
  • be made at every point where the separate insulated conductors are rendered accessible and visible by removal of the outer jacket of the cable;
  • be made by painting or other suitable means; and
  • not render the manufacturer’s numbering of the insulated conductors illegible.

Rule 64-214 provides requirements for overcurrent protection for apparatus and conductors, including:

• Notwithstanding Rules 64-058 and 64-066, individual overcurrent protection devices are required where the sum of the available short-circuit currents from all photovoltaic source circuits connected to the same power conditioning unit is not greater than the rated ampacity of the apparatus or conductors.
• Where overcurrent protection is required by Rule 64-058 for a photovoltaic source circuit, each photovoltaic source circuit must be protected by an individual overcurrent device rated or set at
  • not more than the allowable ampacity of the conductors of the photovoltaic source circuit or
  • the maximum overcurrent protection indicated on the photovoltaic module nameplate, whichever is less.
• For 2-wire photovoltaic circuits that are not solidly grounded, conductors of each source circuit or the conductors of each output circuit may be protected by an overcurrent device that interrupts the current in only one conductor of the circuit.
• Where overcurrent protection devices are used to protect photovoltaic source or output circuits, all overcurrent devices must be placed in conductors of the same polarity for all circuits within a photovoltaic system.
• Where the value as specified above does not correspond to the standard rating of an overcurrent device, the next higher standard rating can be used.
• Overcurrent devices for photovoltaic source circuits must be accessible and grouped where practicable.

Rule 64-216 requires photovoltaic dc arc-fault circuit protection as follows:

• Solar photovoltaic systems with a dc source or dc output circuit voltage of 80 V or greater, when calculated in accordance with Rule 64-202, must be protected by a dc arc-fault circuit interrupter or other system equipment that provides equivalent protection.
• The protection required above must:
  • detect and interrupt arcing faults resulting from a failure in the intended continuity of a conductor, connection, photovoltaic module, or another system component in the dc photovoltaic source and output circuits,
  • not have the capability of being automatically restarted,
  • have annunciation, without an automatic reset, that provides a visual indication that the circuit interrupter has operated; and
  • disable or disconnect inverters or charge controllers connected to the faulted circuit when the fault is detected, or the photovoltaic dc source circuits or dc output circuits either within the combiner, at the module junction box, or at the module cable connectors.

Rule 64-218 provides for photovoltaic rapid shutdown as follows:

• Photovoltaic rapid shutdown must be provided for a photovoltaic system installed on or in buildings where the photovoltaic source or output circuit insulated conductors or cables installed on or in buildings are more than 1 m from a photovoltaic array.
• Notwithstanding the above, photovoltaic rapid shutdown is not required for ground-mounted photovoltaic system circuits that enter a building whose sole purpose is to house photovoltaic system equipment.
• Photovoltaic rapid shutdown must limit photovoltaic source or output circuits located more than 1 m from the photovoltaic array to not more than 30 V within 30 s of rapid shutdown initiation.
• A device used to initiate photovoltaic rapid shutdown must be readily accessible and located for single dwelling units, at the supply authority meter location, for other than single dwelling units, and stand-alone systems at the consumer’s service equipment or supply authority meter location, and
  • at a permanent access to a building roof where an array(s) is installed; or
  • within sight and within 9 m of the array(s).
• The location of the device used to initiate photovoltaic rapid shutdown must be shown on the diagram required in Rule 84-030 2).
• A label indicating that the photovoltaic system is equipped with photovoltaic rapid shutdown must be installed at the supply authority meter and at the consumer’s service equipment locations.

Rule 64-220 applies to attachment plugs and similar wiring devices as follows:

• Attachment plugs and similar wiring devices are permitted to connect cables between photovoltaic modules or between dc photovoltaic source and photovoltaic output circuits, where:
  • there are no exposed energized parts, whether the devices are connected or disconnected,
  • the devices are polarized,
  • the devices have a configuration that is not interchangeable with receptacles or attachment plugs of other systems on the premises,
  • the devices are of the locking type,
  • the devices are rated for the voltage and current of the circuit in which they are installed,
  • the devices provide strain relief,
  • the devices are a mated pair, and
  • the attachment plugs and similar wiring devices are compatible with the types of cables used.
• Where attachment plugs and similar wiring devices installed as above are readily accessible and used in circuits operating at over 30 V, they must be of a type that requires a tool to open the connector.
• Attachment plugs and similar wiring devices must be rated for interrupting current without hazard to the operator or be of a type that requires a tool to open them and be marked “Do Not Disconnect Under Load” or “Not for Interrupting Current.”
• A single-pole attachment plug or similar wiring device designed for dc use may be used as a dc isolation means.
• A multi-pole attachment plug or similar wiring device may be used as an ac isolation means, provided that it complies with the above requirements

Rule 64-222 provides the requirements for photovoltaic module bonding and includes:

• Exposed, non-current-carrying metal parts of photovoltaic modules must be bonded as per Section 10.
• Module bonding connections must be as specified in the module installation manual.
• Notwithstanding the above, bonding connectors intended for bonding photovoltaic modules and installed in accordance with the manufacturer’s instructions may be used.
• The connections to a photovoltaic module must be arranged, so that removal of a single photovoltaic module from a photovoltaic source circuit does not interrupt bonding continuity to the inverter or controller.
• The connections to an inverter or controller must be arranged, so that removal of either the inverter or controller does not interrupt bonding continuity.

Small wind systems

Rules 64-300 to 64-320 apply to small wind systems and include requirements for:

• Providing marking at the disconnecting means of the wind turbine output circuit, specifying:
  • overcurrent protection values,
  • short-circuit current rating,
  • a system description, including the type of generator,
  • rated output current,
  • rated output voltage, and
  • instructions for disabling the turbine.
• Permit the maximum output voltage and accessibility only to qualified personnel.
• Determining the current and temperature rating of supply insulated conductors.
• Wiring methods.
• Provision, rating and location of overcurrent protection for apparatus, power transformers, and conductors.
• Installation, rating, type and location of disconnecting means for circuits and equipment, and in accordance with Rule 84-024.
• Methods of bonding to ground, non-current carrying metal parts of towers, turbine nacelles, other metallic equipment, guy wires, conductor enclosures and metal buildings, in accordance with Section 10.
• Protection of maintenance receptacles with a GFCI, Class A type.
• Installation of lightning protection grounding conductors and electrodes, following Rules 10-706 and 10-702.
• Use of diversion load controllers, and
• Installation and location of surge protective devices.

Large wind systems

Rules 64-400 to 64-414 apply to large wind systems and include requirements for:

• Providing marking at the base of the tower (entrance) of the wind turbine specifying:
  • overcurrent protection values,
  • short-circuit current-interrupting capacity rating for protective devices,
  • a system description, including the type of generator, rated output current, rated output voltage,
  • a warning notice and diagram as per Rule 84-030, and electrical shock and arc flash labels on the wind turbine access door.
• Determining current and temperature rating of supply conductors.
• Provision, rating and location of overcurrent protection for apparatus, power transformers and conductors.
• Installation, rating, type and location of disconnecting means for circuits and equipment and in accordance with Rule 84-020.
• Methods of bonding to ground non-current carrying metal parts of towers, turbine nacelles, other metallic equipment, guy wires, conductor enclosures and metal buildings in accordance with Section 10.
• Installation of station ground electrodes in accordance with Section 36.
• Protection of maintenance receptacles with a GFCI, Class A type.
• Installation of lightning protection grounding conductors and electrodes in accordance with Rules 10-706 and 10-702, and
• Provision of a diagram indicating the demarcation between customer-owned and supply authority systems.

Micro-hydropower systems

Rules 64-500 to 64-512 apply to micro-hydropower systems and include requirements for:

• Providing marking at the disconnecting means of the micro-hydropower system output circuit specifying:
  • the system description,
  • rated power,
  • type of generation system; and
  • rated ballast load voltage and current.
• Determining current and temperature rating of supply conductors.
• Wiring methods.
• Provision, rating and location of overcurrent protection for apparatus, power transformers and conductors.
• Installation, rating, type and location of disconnecting means for circuits and equipment, and in accordance with Rule 84-020.
• Providing for a stand-alone system:
  • an electronic governor,
  • diversion load and identified conductor with a rating equal to the installed capacity, and
  • if battery-based comply with Rules 64-800 to 64-814, and
• Bonding to ground all structures with a minimum No.6 AWG.

 

Hydrokinetic power systems

 

Rules 64-600 to 64-612 apply to hydrokinetic power systems and include requirements for:

• Providing marking for each piece of electrical equipment, in accordance with Rule 2-100, at the disconnecting means or the hydrokinetic turbine electrical system output circuit, including:
  • system description,
  • rated power,
  • type of generation, and
  • rated diversion load voltage and current.
• Determining current, temperature rating and voltage drop of supply conductors.
• For a stand-alone system, an electronic governor, diversion load and identified conductor with a rating equal to the installed capacity, and if battery-based, comply with Rules 64-800 to 64-814.
• Provision, rating and location of overcurrent protection for apparatus, power transformers and conductors.
• Wiring methods.
• Installation, rating, type and location of disconnecting means for circuits and equipment, and in accordance with Rule 84-020.
• Bonding to ground all non-current-carrying metal parts of the turbine, including extra-low-voltage turbines, in accordance with Section 10.

 

Stationary fuel cell systems

 

Rules 64-700 to 64-716 apply to Stationary fuel cell systems and include requirements for:

• Providing marking in accordance with Rule 2-100 at the disconnecting means specifying:
  • the overcurrent protection values provided by the output,
  • short-circuit current-interrupting capacity for protective devices,
  • system description,
  • warning of the storage of electrical energy, and
  • location of the manual fuel shut-off.
• Determining the current temperature rating of supply conductors.
• Provision, rating and location of overcurrent protection for circuit conductors.
• Installation, rating, type and location of disconnecting means for circuits and equipment and in accordance with Rule 84-020.
• Bonding to ground of hydrogen and fuel containers, associated piping, flanges, and hydrogen vent systems with a minimum No. 6 AWG copper bonding conductor, except as required for cathodic protection.
• Location, area classification, and installation in accordance with manufacturers instructions and Section 18, and not located in clothes closets, bathrooms, stairways, high ambient rooms, hazardous locations, or any similar undesirable places.
• Maintaining adequate airflow into or exhaust out of the stationary fuel cell system and suitability for installation in an outdoor location.
• Marking as suitable for indoor installations.
• Installation of dry type transformers in rooms containing fuel cell power systems.
• Providing interlocked mechanical ventilation that provides alarm and shut down of the fuel cell power system upon loss of ventilation.
• Providing an automatic shut-off valve located outdoors, interlocked with indoor combustible gas detection for fuel cell power systems fuelled by a non-odorized gas.
• Provision of interconnection to fuel supply shut off with an automatic fire suppression system.

 

Storage batteries

Rules 64-800 to 64-814 apply to storage batteries and include requirements for:

• Installation in dwelling units and in accordance with the provisions of

Rule 26-540, or as required by the manufacturer.

• Provision of current-limiting overcurrent devices in each battery circuit, where the available short-circuit current from a battery, or battery bank, exceeds the interrupting or withstand ratings of other equipment in that circuit.
• Installation of flooded, vented, lead-acid batteries in non-conductive cases or racks and near other conductive materials.
• Provision of disconnects for maintenance, for series connected strings and grounded circuit conductors for batteries, subject to field servicing, and operating at more than 48 v nominal.
• Operation of battery systems of more than 48 V nominal, with ungrounded conductors, provided:
  • source and output circuits comply with Rule 64-066,
  • dc and ac loads are grounded,
  • all main ungrounded battery circuit conductors are provided with disconnecting means, over current protection, and a ground fault detector and indicator.
• Battery interconnections with hard-service use and moisture-resistant, flexible cables.
• Provision of charge control equipment accessible only to qualified persons.
• Providing additional, independent means to prevent overcharging, where the sole means of regulating the battery charging is a diversion charge controller.
• Determining the diversion load’s current, voltage and power rating, conductor ampacity, and the over-current device for the diversion charge controller.
• Providing an independent means of controlling the battery charging process for systems using interactive inverters to divert excess power into the utility system when the utility is not present or the primary charge controller fails.

In the next installment, we will discuss Section 66 — Amusement parks, midways, carnivals, film and TV sets, TV remote broadcasting locations and travelling shows.

 

^[i] William (Bill) Burr is an associate member of the Canadian Electrical Code, Part 1, Technical Committee and formerly Chair of the Canadian Advisory Council on Electrical Safety (CACES), Chief Electrical and Elevator Inspector for the Province of BC & the Northwest Territories, Director of Electrical and Gas Standards Development and Director of Conformity Assessment at CSA Group. Bill can be reached at Burr and Associates Consulting billburr@gmail.com..