2728

THE NEW ZEALAND GAZETTE.

[No. 73

44. LIGHTNING-ARRESTERS.
    Where any portion of any electric line, or support for an
    electric line, is exposed in such a position as to be liable to
    injury from lightning it shall be effectively protected against
    injury by suitable lightning arresters.
    Earth-wires for circuits or equipments shall not be utilized
    for also earthing lightning-arresters, for which a separate
    earth-connection must be provided.

45. TRANSFORMERS.
    Where transformers are placed on poles they shall be fitted
    with watertight cases, and either thoroughly protected against
    interference or attached to the poles at such a height as to
    make them inaccessible except by means of a ladder or other
    special appliance. Where pole-platform type of construction
    is adopted a substantial railing shall be built around the
    platform. Where transformers are placed within a building
    or enclosure the same shall be inaccessible except to authorized
    persons; all high-pressure or extra-high-pressure
    conductors therein shall be screened and protected against
    accidental contact. Each pole-transformer shall be equipped
    with primary fuses. The cases of all transformers, whether
    within or without a substation, shall be earthed by a copper
    conductor in accordance with the rules for earthing. Pole-steps shall not be placed less than 9 ft. above the ground-level.

46. MOTOR, GENERATOR, AND ELECTRIC COOKING-RANGE INSTALLATIONS.
    The frames of fixed motors, generators, and electric cooking-ranges shall be earthed in accordance with the rules of the
    Institution of Electrical Engineers of Great Britain for earthing.
    All metal casings of switches, resistances, fuses, cables,
    and wires shall be earthed also in accordance with such rules.
    The earth-wire shall be of sufficient current-carrying capacity
    for the protection of the apparatus to which it is connected.
    The minimum sectional area shall be 0·003 square inches (No.
    16 S.W.G.), and the maximum shall be 0·028 square inches
    (No. 6 S.W.G.) Reliance on partial or variable insulators
    (such as concrete foundations) between the frame and adjacent
    grounded parts does not offer suitable protection either
    for equipment or attendants.
    Every motor must be controlled by a quick-break protected
    switch conveniently placed so that the person in charge of
    the motor can cut off the supply from the motor and from
    all auxiliary devices connected therewith.
    Fuses or other automatic cut-out must be provided to protect
    effectively the conductors in each circuit from excess of
    current.
    Every precaution shall be taken in choosing positions for
    and in wiring and setting-up of motors, generators, and electric
    cooking-ranges, and the necessary devices in connection therewith, so as to eliminate all risk of fire or shock.
    Terminals of motors, generators, and electric cooking-ranges
    must be so guarded that they cannot be accidentally touched
    or short-circuited.
    The insulation resistance to earth of each motor, generator,
    and electric cooking-range circuit, including all auxiliary
    devices, shall not be less than 1 megohm.

47. ARC LAMPS.
    All arc lamps shall be so guarded as to prevent pieces of
    ignited carbon or broken glass falling from them, and shall
    not be used where there is any danger arising out of the
    presence of explosive dust or gas.
    Arc lamps or any part thereof used in any street for public
    lighting shall be at least 10 ft. from the ground.
    Arc lamps used in any street for private lighting shall be
    at least 8 ft. from the ground, and shall be so screened as
    to prevent risk of contact with persons.
    Arc lamps must be insulated from earth, and be fixed so
    that they cannot swing into contact with any substance,
    metallic or otherwise, that might connect them with earth.
    Every precaution must be taken against the danger of
    shock during trimming of arc lamps.
    Resistances for the regulation of arc lamps, if exterior to
    the lamp, shall be mounted on incombustible bases, shall be
    so placed that they cannot by conduction or radiation set
    fire to any contiguous material, and shall be of ample size
    to carry with safety the maximum current that normally
    flows through them.
    Each arc-lamp circuit, if wholly insulated, shall be provided
    with a fuse on each pole, but if one terminal is connected
    to an earthed neutral or intermediate conductor a fuse shall
    not be inserted in the connection to the neutral or intermediate
    conductor.

48. UNDERGROUND CONDUCTORS.
    Underground conductors shall be thoroughly insulated, and
    shall be protected from mechanical damage by steel armouring, wooden boxing, or earthenware, stoneware, concrete,
    iron, or fibre conduits or pipes. They shall be laid, wherever
    possible, under the footpaths, and with a cover of at least
    9 in. from the surface of the pavement. Where laid under
    the roadway this cover shall be not less than 2 ft.

Except by permission of the Minister of Telegraphs, all
underground electric lines must be placed on the same side
of the street as overhead electric lines, and on the opposite
side of the street to that on which underground or overhead
telegraph-lines exist.
All conduits, pipes, casings, and street-boxes used as receptacles for electric lines shall be constructed of durable
material, and shall be of ample strength to prevent damage
from heavy traffic; and reasonable means shall be taken to
prevent the accumulation of gas in such receptacles.
Where any underground electric line crosses or is in
proximity to any metallic substance, special precaution shall
be taken by the licensee against the possibility of any electrical
charging of the metallic substance from the electric line, or
from any metallic conduit, pipe, or casing enclosing such line.
Where any underground electric line is brought through
the surface of the ground to connect with overhead electric
lines it shall be completely enclosed in an effectively earthed
metal pipe for a height of at least 12 ft. above the ground.
Electric lines placed in a tunnel or subway not in the sole
occupation of the licensee must be insulated and protected
by a metallic sheath or enclosed in a metal pipe, both being
effectively earthed.
When any high or extra-high pressure electric line is laid
beneath the surface of the ground efficient means shall be
taken to render it impossible that the surface of the ground,
or any other electric line or conductor, shall become charged
by leakage from the high or extra-high pressure electric line.
A high or extra-high pressure electric line shall not be used
for the supply of energy before it has been completely laid,
properly jointed, examined, and tested.

49. STREET-BOXES.
    The covers of street-boxes shall be so secured that they
    cannot be opened except by means of a special appliance;
    and such boxes shall be inspected from time to time for the
    presence of gas, and suitable action shall be taken to check
    the influx and accumulation of gas.

50. EARTHING CONDUITS.
    All metal conduits, pipes, or casings containing high or
    extra-high pressure electric lines shall be effectively earthed,
    and shall be so jointed and connected across all street-boxes
    and other openings as to make good electrical contact throughout their whole length.

51. INSULATION OF ELECTRIC LINES.
    Every low-pressure electric line, after having been placed
    in position and before it is used for the purpose of supply,
    shall be tested for insulation at a pressure of at least 500 volts,
    and the licensee shall keep a record of the results of such
    tests.
    A high or extra-high pressure electric line shall not be
    brought into use until it has withstood the continuous application for half an hour of the maximum pressure for which
    the electric line is to be used. A record of such test shall
    be kept by the licensee.
    The insulation of every complete circuit used for the supply
    of energy, including all machinery, apparatus, and devices
    forming part of or in connection with such circuit, shall be
    so maintained that the leakage-current shall not under any
    condition exceed one-thousandth part of the maximum supply-current. Suitable steps shall be taken to promptly locate
    such leakage, and every such leakage shall be remedied without delay.

52. ELECTRIC-SERVICE LINES.
    Service connections from aerial lines shall be taken direct
    from insulators, and shall not be tapped off the aerial lines
    between supports. They shall be led as directly as possible
    to insulators firmly attached to some portion of the consumer's premises which is not accessible to any person without the use of a ladder or other special appliance. Service leads must not be brought out through the roof or attached to
    insulators fixed on the roof of a building. The portion of
    any low-tension electric-service line passing over a street shall
    be not less than 18 ft. above the crown of the road. Within
    the boundary of the consumer's property the height of the
    low-tension electric-service lines shall be not less than 14 ft.
    above the ground-level; provided that if the conductors other
    than earthed conductors are bare such height shall be not
    less than 16 ft. High-pressure or extra-high-pressure service
    lines shall be of a height not less than those specified in
    clause 33.
    Every portion of any electric-service line, except an earthed
    neutral or intermediate conductor, which is outside a building
    shall be effectively protected by triple braiding or rubber
    insulation in the span between the pole and the building.

53. SERVICE CONNECTIONS.
    The licensee shall be responsible for all electric lines, wires,
    fittings, and apparatus, belonging to it or under its control
    which may be upon a consumer's premises, being erected and
    maintained in a safe condition and in all respects fit for
    supplying energy.