Schedule 3—Requirements for substations
(regulation 51)
Building Code of Australia means the Building Code of Australia as published from time to time;
ground type substation means a substation that is a semi‑enclosed, free‑standing substation connected to a high voltage aerial line or underground line;
kiosk padmount type substation means a substation that is a totally enclosed, free‑standing, self‑contained substation not designed for bodily entry, generally operated from door openings;
listed standards means the standards (both national and international), codes, guides and other documents, as published from time to time, listed in the Appendix at the end of this Schedule.
2—Design
(1) Substations must be designed so that—
(a) buildings and enclosures are secure; and
(b) plant, equipment and lines have safe levels of electrical insulation; and
(c) plant, equipment and lines will carry electrical load currents for which they are designed without failure; and
(d) plant, equipment and lines will carry short circuit currents which will enable the correct operation of protective devices,
so as to comply with the listed standards or achieve, to the satisfaction of the Technical Regulator, the same or better safety and technical outcomes.
(2) In determining electrical service conditions and the physical environment under which the line will operate, due care must be given to the consideration of extremes that may occur, the likelihood of their occurrence and the associated risks.
3—Plant and equipment
All substation plant and equipment must conform to the listed standards or achieve, to the satisfaction of the Technical Regulator, the same or better safety and technical outcomes.
4—Clearances to live equipment and lines
(1) Substations must be designed to provide safe operating and working clearances from live equipment and lines.
(2) Clearances between live equipment to structures and buildings and the provision of safe operating and working clearances must be determined in accordance with the listed standards.
5—Containment of insulating liquids
Buildings must be designed in respect of the containment of insulating liquids in an enclosure or in an area in which the equipment is housed so as to comply with the listed standards or achieve, to the satisfaction of the Technical Regulator, the same or better safety and technical outcomes.
6—Security of substation buildings and enclosures
(1) Buildings and enclosures must be secured so as to prevent entry by unauthorised persons.
(2) Buildings and enclosures must have signs on all entrances prohibiting unauthorised entry and warnings of the danger associated with unlawful entry.
(3) The ventilation system of buildings and enclosures must be designed so to prevent the intrusion of foreign objects into the building or enclosure likely to interfere with the safe operation of the electrical equipment.
7—Kiosk padmount type substations
The installation design of a kiosk padmount type substation must ensure that no part of the kiosk enclosure is within 1.2 m of any part of a building or wall that has a fire rating less than 3 hours as determined by the Building Code of Australia.
8—Ground type substations
(1) The calculations for the design of structures supporting aerial lines in ground type substations must, in addition to allowing for the maximum loading in accordance with Schedule 1, also allow for forces under short circuit conditions.
(2) Walls and fences enclosing a ground type substation must be designed—
(a) so that the minimum horizontal clearances from any building or structure (including fences or walls which are not solid) within the boundary, or forming the boundary of the ground type substation to any live and bare equipment is sufficient to ensure safe operating conditions;
(b) to be constructed of a substantive material (such as brick, masonry, wood, sheet metal or galvanised chain‑wire mesh with an aperture dimension of not more than 0.05 m) and be a minimum height of 2.5 m.
(3) The top 0.5 m of a wall or fence enclosing a ground type substation may consist of securely supporting barbed wire, or razor wire, with a maximum separation of the strands of 0.15 m or tiger tape flat loops.
(4) Clearances between any building or structure within the boundary of the ground type substation and any live equipment must be determined so as to comply with the listed standards or achieve, to the satisfaction of the Technical Regulator, the same or better safety and technical outcomes.
9—Pole mounted substations
Pole mounted substations must be designed so that—
(a) the calculations for the design of structures supporting aerial lines and busbars in substations, in addition to allowing for the maximum loading in accordance with Schedule 1, also allow for forces under short circuit conditions;
(b) all parts of supporting platforms and equipment which are mounted on or attached to the pole or cross arms, except for conductors, are at height not less than that set out in Table 1;
(c) any equipment mounted at a height less than that prescribed in paragraph (b), is less than 0.2 m from the surface of the pole and at least 0.5 m from the vertical projection of the kerb line of any road.
TABLE 1: Heights of supporting platforms and mounted equipment
Outside 0.5 m of the vertical projection of the kerbline (on the non road side) of any road
Elsewhere
Height above ground surface
3.6 m
4.6 m
10—Installation
Substations must be installed to the requirements of a design that complies with the requirements of this Schedule.
11—Maintenance
(1) Substations, substation enclosures, associated plant, components and lines must be maintained in a safe operating condition.
(2) A system of maintenance must be instituted for substation buildings and enclosures and associated plant, equipment and lines, including—
(a) predetermined processes to confirm the safe state of components; and
Appendix—Standards, codes, guides and other documents relating to substations
(a) IEC means International Electrotechnical Commission;
(b) IP Code means International Protection Code.
Electrical design
Switchgear assemblies & ancillary equipment for alternating voltages above 1 kV
Circuit breakers and ancillary equipment
High voltage ac switchgear and controlgear - Circuit breakers for rated voltages above 1 000 V
AS 2006
Switchgear assemblies and ancillary equipment
High voltage switches - Switches for rated voltages above 1 kV and less than 52 kV
AS/NZS 60265
High voltage, ac switchgear and controlgear - Switches and switch‑disconnectors - For rated voltages of 52 kV and above
AS 1025
High voltage ac switchgear and controlgear - Disconnectors (isolators) and earthing switches
AS 1306
High voltage ac switchgear and controlgear - Switch‑fuse combinations
AS 2024
Common specifications for high‑voltage switchgear and controlgear standards
AS/NZS 2650
AC metal‑enclosed switchgear and controlgear for rated voltages above 1 kV and up to and including 72.5 kV
AS 2086
AC insulation‑enclosed switchgear and controlgear for rated voltages above 1 kV and up to and including 38 kV
AS 2264
Insulating liquids - Specifications for unused mineral insulating oils for transformers and switchgear
AS 1767
Control equipment
Low voltage switchgear and controlgear - General rules
Low voltage switchgear and controlgear - Switches, disconnectors, switch‑disconnectors and fuse combination units
AS/NZS 3947
Low voltage switchgear and controlgear - Contactors and motor starters: Electromechanical contactors and motor starters
Low voltage switchgear and controlgear - Circuit control devices and switching elements - Electromechanical control circuit devices
Low voltage switchgear and controlgear - Control circuit devices and switching elements - Proximity switches
Insulating panels
Sheets and boards for electrical purposes - Classification and general requirements
AS 1795
Sheets and boards for electrical purposes - Dimensions of switchboard panels
AS 1795
Power transformers
Power transformers - General
Power transformers - Temperature rise
Power transformers - Insulation levels and dielectric tests - General requirements
Power transformers - Insulation levels and dialectric tests - External clearances in air
Power transformers - Ability to withstand short circuit
Power transformers - Determination of transformer and reactor sound levels
Insulating liquids - Specification for unused mineral insulating oils for transformers and switchgear
AS 1767
Bushings
Bushings for alternating voltages above 1 000 V
AS 1265
Surge arresters
Surge arresters (diverters) - Silicon carbide type for ac systems
AS 1307
Surge arresters - Metal‑oxide surge arresters without gaps for ac systems
AS 1307
Batteries
Stationary batteries - Lead‑acid - Vented type
AS 4029
Stationary batteries - Lead‑acid - Valve‑regulated type
AS/NZS 4029
Stationary batteries - Lead‑acid - Pure lead positive pasted plate type
AS 4029
Insulation coordination
Insulation coordination - Definitions, principles and rules
AS 1824
Insulation coordination (phase‑to‑earth and phase‑to‑phase, above 1 kV) - Application Guide
AS 1824
Insulation coordination for equipment within Low Voltage systems: Principles, requirements and tests
IEC 60664
Safety clearances
Buildings and enclosures
Building Code of Australia
Fixed platforms, walkways, stairways and ladders: Design construction and installation
AS 1657
The use of ventilation and air conditioning in buildings - Ventilation design for indoor air contaminant control
AS 1668
The use of ventilation and air conditioning in buildings - Fire and smoke control in multi‑compartment buildings
AS/NZS 1668
The storage and handling of flammable and combustible liquids
AS 1940
Oil containment
Environment Protection Authority
Electrical installations - Secondary batteries installed in buildings - Vented cells
AS 3011
Electrical installations - Secondary batteries installed in buildings - Sealed cells
AS 3011
Switchyard structures, footings and foundations
Structural design actions - General principles
Structural design actions - Permanent, imposed and other actions
Structural design actions - Wind actions
Minimum design loads on structures (known as the SAA Loading Code) - Earthquake loads
AS 1170
Design of steel lattice towers and masts
AS 3995
Steel structures
AS 4100
Concrete structures
AS 3600
Guide to maintenance and supervision of insulating oils in service
AS 1883
Maintenance of electrical switchgear
AS 2467
Guide to the installation, maintenance, testing and replacement of secondary batteries in buildings - Vented cells
AS 2676
Guide to the installation, maintenance, testing and replacement of secondary batteries in buildings - Sealed cells
AS 2676