1928

THE NEW ZEALAND GAZETTE

No. 47

(f.) “Consumer’s wires” means any electric lines on the consumer’s premises which are connected with the said Council’s electric lines.

(g.) “Street” includes road.

(h.) “Telegraph” includes telephone.

1. Supply shall be on the following systems:—

(a.) For general supply, three-phase 50 cycle alternating current, at 230 and 400 volts, four-wire system.

(b.) For special motor supply, 550 volts direct current.

(c.) For street lighting, constant-current alternating-series system up to a maximum of 3,000 volts, and direct current 550 volts from trolley-wire.

(d.) For supplying outlying districts, single-phase alternating current, 50 cycles, transmitted at a pressure of from 2,300 to 2,500 volts and transformed to 230 volts for distribution.

2. The said Council shall, before the erection or construction of any part of the work hereby authorized is begun, submit for the approval of the Minister such plans and other information showing and describing such work as he may require. In the case of any alteration involving departure from the method of construction shown on the deposited-plans, the said Council shall submit plans showing such alterations for the Minister’s approval, and with such approval the alterations may be duly carried out.

The neutral wire of the three-phase system shall be earthed at the power-station, and otherwise insulated throughout its length. The earth connection shall be made through a low-reading ammeter, the readings of which shall be recorded daily.

3. At the generating-station a properly equipped non-inflammable switchboard mounted upon a substantial iron frame shall be provided. All conductors must be so guarded that no unauthorized person can under any circumstances come in contact therewith.

4. The distribution may be carried out either by underground or overhead conductors; provided that if at any time it is deemed by the Minister to be detrimental to the public safety for the conductors or any particular class of conductors to be overhead, they shall, on receipt of notification to that effect from the Minister, and within nine months of such notification, be laid underground, and all consequent and necessary alterations made by and at the cost of the said Council.

Transformers shall be placed either on poles or in sub-stations. The cases of all transformers shall be earthed by means of a copper conductor at least ·022 square inch in section. Within sub-stations all high-tension conductors shall be thoroughly insulated, or otherwise protected from accidental contact; the walls shall be lined with sheet asbestos or other insulating material. A substantial insulating rubber mat and rubber gloves shall be supplied, and the sub-station shall be entirely inaccessible to unauthorized persons.

5. Overhead conductors shall be of stranded hard-drawn copper or aluminium wire of not less than 0·012 square inches in sectional area, provided that service wires of short span may be not less than 0·007 square inches in sectional area.

All wires at a pressure over 600 volts shall be concentric, and shall be suspended from suitable steel bearer-wires. The outer conductor shall be triple braided, and shall be earthed at the generating-station.

All wires at a pressure below 600 volts shall be covered with a triple braiding of jute thoroughly impregnated with insulating compound; provided that the neutral conductor of the three-phase system may be bare.

The stress in overhead conductors shall not exceed 28,000 lb. per square inch for copper and 15,000 lb. per square inch for aluminium in the extreme case of a temperature of 12° Fahr. and a wind-pressure of 18 lb. per square foot of diametrical plane occurring simultaneously. The span between supports and the sag shall be determined to conform with the above limiting stresses.

No overhead electric lines shall come within 3 ft. of any other aerial wires or cables, except where it may be permitted to pass the lines between other wires at a pole or support.

6. All overhead wires shall be carried at a minimum height of 20 ft. over road crossings, and 18 ft. elsewhere.

All aerial wires shall be attached to suitable insulators carried on cross-arms of suitable material and cross-section, and they shall be so attached to the insulators or guarded that they cannot fall away from the support. Conductors covered with insulating material shall be so attached that their insulation will not be impaired where they are secured to the insulator.

Every support for an aerial line shall be of durable material and properly strengthened against force due to wind-pressure, change of direction of line, and unequal length of span. The factor of safety of such supports shall be at least 4 if of iron, steel, or reinforced concrete, and 6 if of wood, taking into consideration all possible stresses, including wind-pressure at 30 lb. per square foot on plane surfaces and 18 lb. per square foot of diametrical plane for cylindrical surfaces.

7. Except by permission of the Minister of Telegraphs, all overhead electric-light pole lines shall be placed on the opposite side of the streets to that on which any telegraph lines exist, and where the erection of the electric-light wires necessitates the alteration of any existing telegraph wires, and such alteration is approved by the Minister of Telegraphs, the expense of the alteration shall be borne by the said Council.

Where the electric-light wires are on one side of the street and the telegraph wires on the other, and service is required to be given from either to the other side of the street, the said Council and the Minister of Telegraphs shall give to each other reasonable facilities as far as possible to effect supply.

In running the lines authorized by this license through streets where no telegraph line exists the said Council shall keep to the one side of the street, and in running wires to the opposite side of the street the said Council shall arrange so as to interfere as little as possible with the route of any future telegraph line.

8. Where electric lines cross telegraph lines they shall be insulated and protected in such manner as is required by the Minister of Telegraphs.

Where wires are run on the telegraph poles the number of such wires shall be limited to one circuit of not more than four wires. Wires shall be supported as far as possible on a bracket-arm on one side of the pole. Where the wires are placed on both sides of the pole a space of 3 ft. in the clear shall be left between the group of wires on the one side of the pole and the group of wires on the other side of the pole. The neutral wire shall be placed nearest the pole. Wires at a pressure of 600 volts and under shall be covered with a triple braiding of jute thoroughly impregnated with insulating compound. Wires at a pressure of over 600 volts shall be concentric, and shall be suspended from suitable steel bearer-wires. The outer conductor shall be triple braided, and earthed at the generating-station. The neutral conductor of the three-phase system may be bare.

Notice of any change or alteration to be made to the electric lines shall be given to the District Engineer of the Telegraph Department. If required, by notice in writing from the District Engineer of the Telegraph Department, to remove any electric line or lines from any telegraph pole, the Council shall remove such line or lines within thirty days of the receipt of such notice.

9. If the Minister of Telegraphs so requires, efficient guard-wires shall be erected in a manner to meet with the approval of that Minister at all crossings and places where either transmission or distribution electric-lighting wires intersect telegraph wires. The said Council shall bear the expense of such guard-wires in all cases where an electric-lighting wire intersects a telegraph wire previously existing.

10. Where any portion of an electric line or any support for an electric line is exposed in such a position as to be liable to injury from lightning, it shall be efficiently protected against such liability.

11. Service lines from aerial lines 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. Every portion of any service line which is outside a building but is within 7 ft. from any part of the building shall be rubber-insulated.

12. No work of any nature shall be erected or constructed in pursuance of this license upon, over, or under any part of the New Zealand Government railways until the said Council has obtained the consent of the Minister of Railways thereto, as required by section 4 of the Government Railways Amendment Act, 1910 (No. 2).

13. Every aerial line, including its supports, its conductors, and their insulating covering, and all the structural parts and electrical appliances and devices belonging to or connected with the line, shall be duly and efficiently supervised and maintained as regards both electrical and mechanical conditions.

14. An aerial line shall not be permitted to remain erected after it has ceased to be used for the supply of energy, unless the said Council intends within a reasonable time again to take it into use.

15. All metal pipes or coverings containing any electric line or wire shall be efficiently connected with earth, and shall be so jointed as to make good electrical connection throughout their whole length.

16. Underground conductors shall be thoroughly insulated, and shall be protected from mechanical damage by a wooden boxing or earthenware or stoneware conduit. They shall be laid wherever possible under the footpaths,