Electricity Act

Electricity (Safety of Low Voltage and Medium Voltage Electrical Installations) Regulations 2004

[GN 74 of 2004 – 1 July 2006] [Section 49]

1. These regulations may be cited as the Electricity (Safety of Low Voltage and Medium Voltage Electrical Installations) Regulations 2004.

2. In these regulations –

"circuit" means an assembly of electrical equipment supplied from the same origin and protected against over current by the same protective device;

"earth" means the conductive mass of the earth, whose electric potential at any point is conventionally taken as zero;

"earth electrode" means a conductor or a group of conductors in intimate contact with, and providing an electrical connection to, earth;

"electrical appliance" means equipment using low voltage or medium voltage electricity other than a luminaire or an independent motor;

"electrical installation" means an assembly of associated electrical equipment with co-ordinated characteristics which fulfils a specific purpose;

"extraneous conductive part" means a conductive part liable to introduce an electric potential but not forming part of an electrical installation;

"final circuit" means a circuit connected directly to an equipment using electricity, a socket outlet or other outlet point for the connection of that equipment;

"mains" means the main switchboard of a building;

"new consumer" means a consumer who is supplied with electrical energy by the Board on or after 1 October 2004;

"over current protective device" means a mechanical switching device or association of devices intended to cause the opening of the contacts when the current in a circuit attains or exceeds the rated value of the circuit;

"residual current" means leakage of electrical current in a circuit flowing to earth or to any extraneous conductive part;

"residual current device" means a mechanical switching device or association of devices intended to cause the opening of the contacts when the residual current attains a given value under specified conditions;

"switchboard" means an assembly of protective devices used for the operation, regulation, protection or control of an electrical installation;

"TN system" means a system having one point of the source of electrical energy directly earthed, the exposed conductive parts of the installation being connected to that point by protective conductors;

"TT system" means a system having one point of the source of electrical energy directly earthed, the exposed conductive parts of the installation being connected to earth electrodes electrically independent of the earth electrodes of the source.

3. These regulations shall apply to low voltage and medium voltage electrical installations in all buildings.

4. (1) Every electrical installation in a building shall be fitted at the mains with a residual current device which shall have –

 (a) an operating electrical current of 30 milliamperes or less; and

 (b) an operating time of 40 milliseconds or less at 150 milliamperes.

(2) Notwithstanding paragraph (1), a residual current device of a higher rating than those specified in paragraph (1) may be installed at the mains, provided that the final circuit of the electrical installation is protected by a residual current device of ratings specified in paragraph (1).

5. (1) Subject to paragraphs (2) and (3), every circuit of a TT or TN system to which an electrical appliance is connected shall be protected by an over current protective device and a residual current device.

(2) No residual current device shall be used in the circuit of a TN system where the neutral and the protective functions of that circuit are combined in one conductor.

(3) A single device performing the functions of both an over current device and a residual current device may be used to protect the circuit of a TT or TN system to which an electrical appliance is connected.

6. Every residual current device used in any circuit shall disconnect both the phase and the neutral conductors.

7. (1) The Board shall not supply electricity to any new consumer unless the electrical installation on the premises of that consumer meets the requirements specified in regulation 4.

(2) The Board shall not be liable civilly or criminally by reason only of having supplied electricity to any new consumer in breach of paragraph (1).

8. 

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Electricity Regulations 1939

[GN 31 of 1939 – 21 July 1939] [Section 49]

1. Short title

These regulations may be cited as the Electricity Regulations 1939.

2. Interpretation

"Act" means the Electricity Act;

"alternate fixture" means 2 electric lamps controlled by one or more switches in such a manner that only one of the 2 lamps can be supplied with electric energy at a time;

"apparatus" –

(a) means electric apparatus; and

(b) includes all machines, apparatus and fittings in which conductors are used or of which they are a part;

"authorised person" means a person employed, appointed or selected by a user, an undertaking, a consumer or jointly in cases where any electric lines or apparatus are in the joint charge of an undertaking and another person, to carry out duties incidental to the generation, transformation, distribution or use of energy, where the person is competent for the purposes of the regulation in which the term is used;

"circuit" means an electrical circuit forming a system or a branch of a system;

"conductor" means a wire used for the supply of energy and arranged to be electrically connected to a system;

"connected with earth" means connected with the general mass of earth in such a manner as will ensure, at all times, an immediate and safe discharge of energy;

"consumer's terminals" means –

(a) supply terminals; and

(b) the point or points on the consumer's premises at which the supply of energy is delivered to the consumer from the service line;

"consumer's wiring" means the electric lines situate on the consumer's side of the supply terminals;

"dead" means at or about earth potential and disconnected from any live system;

"Director" has the same meaning as in the Utility Regulatory Authority Act;

"domestic electric appliance" means an electric appliance such as a cooker, heater, flat iron, kettle, wash boiler, water heater, vacuum cleaner, fan, wireless set or sterilizer which may be used for household services or for personal comfort;

"electrical equipment" means an installation or part of an installation;

"feeder" means an electric line to which service lines are not normally connected;

"final sub-circuit" –

(a) means an outgoing circuit connected to one way on a distribution fuse board and intended to supply energy at one or more points to current using appliances without the intervention of a further distribution fuse board; and

(b) includes all branches and extensions which are derived from that particular way on the board;

"fixed lamp" means a lamp so connected to the consumer's installation that it can be supplied with electric energy therefrom without the restrictions associated with alternate fixtures;

"installation" means –

(a) the operation of erecting and connecting up the necessary plant and equipment for the application of electricity on any particular premises or for a specific purpose;

(b) the complete plant and equipment necessary for the application of electricity on any particular premises or for a specific purpose;

"insulation" means a non-conducting material enclosing, surrounding or supporting a conductor of such quality and thickness as to be suitable for the purposes of the article in which the term is used;

"lamp" means an electric lamp used for illumination purposes in which metal, carbon, composite or other filament or gas is rendered incandescent by the passage of an electric current;

"lighting fixture" means a fixed lamp or an alternative fixture;

"line conductor" means a conductor forming part of a system and used for the transmission or supply of energy, including so much of any service line as may be under the control of an undertaking;

"live" means electrically charged;

"metal structure" means metal earth guards, metal or part metal line supports, stay wires, metal parts of buildings, and all metal parts not ordinarily intended to conduct energy;

"month", unless otherwise specified, means, for the purposes of these regulations and of any other regulations or orders made under the Act, the period between the regular monthly watt-hour meter reading and the next regular monthly watt-hour meter reading;

"order" means a direction in writing or printing or part in writing and part in printing;

"overhead line" means an electric line which is placed above ground and in the open air;

"permanently and solidly earthed" means an efficient electrical connection to the general mass of the earth and, in the case of a line conductor at least as often as once in every half-mile length of the conductor and without a fuse-link, switch, circuit breaker, resistor, or impediment in the earth connection, so that the total resistance between any such electrical connection and the earth shall not at any time exceed 10 ohms;

"permanently and solidly earthed wire" means a wire that is permanently and solidly earthed but which does not form part of a system;

"power factor" means the ratio of the total watts to the total equivalent volt-amperes;

"public road" means any street, road, thoroughfare, avenue or square;

"switchboard" –

(a) means an assemblage of switch gear or fuses, conductors, and other apparatus, with or without instruments, for controlling the distribution of energy, or for controlling or protecting electrical circuits, machines, and current-using appliances; but

(b) does not apply to a group of local switches on a final sub-circuit where each switch has it own insulating base;

"switch station" –

(a) means any premises or enclosure, large enough to admit the entrance of a person after the apparatus therein is in position, containing apparatus for switching, controlling or otherwise regulating energy at a voltage above medium voltage but not for transforming or converting energy (other than transforming or converting solely for the operation of switch gear or instruments); and

(b) includes the apparatus therein;

"town" means Port Louis, Curepipe, Quatre Bornes, Beau Bassin-Rose Hill and Vacoas-Phoenix;

"undertaking" has the same meaning as in the Utility Regulatory Authority Act;

"user" means the occupier of premises containing an installation;

"voltage" means electric pressure and electro-motive force, and in particular the voltage, as measured by a suitable voltmeter, between any pair of conductors forming part of a system or between any point of either conductor and the earth;

3. Application of regulations

These regulations shall apply to every undertaking and installation for the generation, transformation, distribution and use of energy for public and private purposes:

Provided that they shall not apply to any process or apparatus used exclusively for electrochemical or electrothermal or testing or research purposes where the process is worked, the apparatus is constructed and protected and such special precautions as may be necessary to prevent danger are taken in a manner approved
by the Director.

4. Electric line supports

Electric line supports, unless otherwise authorised in writing by the Director, and subject to the conditions of such authorisation, shall be confined to one side only of every public road and railway:

Provided that this regulation shall not apply to supports used for the purpose of carrying service lines from one side to the other of a public road or railway, unless the supports interfere with the wires of other public services.

5. Material of line conductors

Line conductors shall be of copper, cadmium copper, aluminium, bronze, or other material approved by the Director.

6. Minimum size of line conductors

(1) The minimum permissible size for copper and other line conductors (other than service lines and permanently and solidly earthed line conductors) shall be such as to have an actual breaking load of not less than 1,237 pounds, the equivalent minimum cross-sectional area and weight per mile for copper being –

Conductor

Cross-sectional area, square inches

Weight per mile lbs

No. 8 British Standard Wire Gauge

0.0201

409

Provided that the minimum permissible size for copper and other line conductors erected outside a town for service lines and permanently and solidly earthed line conductors shall be such as to have an actual breaking load of not less than 816 pounds, the equivalent minimum cross-sectional area and weight per mile of copper being –

Conductor

Cross-sectional area, square inches

Weight per mile lbs

No. 10 British Standard Wire Gauge

0.0129

262

Provided that permanently and solidly earthed line conductors and service lines connected thereto, which do not cross a public road may have an actual breaking load of not less than 500 pounds, the equivalent cross-sectional area and weight per mile of copper being –

Conductor

Cross-sectional area, square inches

Weight per mile lbs

No. 12 British Standard Wire Gauge

0.0085

160

(2) Where required by the Director, line conductors which are permanently and solidly earthed shall be of the same material and cross-section as the unearthed line conductors of the same circuit.

(3) Paragraphs (1) and (2) shall apply to electric lines erected or reconstructed on or after 1 July, 1943.

(4) The minimum permissible size for copper and other line conductors, and of service lines and permanently and solidly earthed line conductors which cross public roads, shall be such as to have an actual breaking load of not less than 816 pounds, the equivalent cross-sectional area and weight per mile of copper being as follows –

Conductor

Cross-sectional area, square inches

Weight per mile lbs

No. 10 British Standard Wire Gauge

0.0129

262

Provided that service lines and permanently and solidly earthed line conductors which do not cross public roads and have a distance between any 2 adjacent supports not exceeding 100 and 75 feet, and which consist of such material and are erected in such manner that the actual breaking load of the said line conductors and service lines, including attachments therefor is not less than 330 pounds, may be used, the equivalent cross-sectional area and weight per mile for copper of the wire used being as follows –

Conductor

Cross-sectional area, square inches

Weight per mile lbs

No. 14 British Standard Wire Gauge

0.005

102

[Reg. 6 amended by s. 3 of Act 70 of 1951 w.e.f. 20 December 1951.]

7. Line conductors to be inaccessible

(1)Line conductors shall be rendered inaccessible to any person from any building or other place without the use of a ladder or other special appliance.

(2) Regard shall be had to the normal use by the public or the occupier of any premises or land and where necessary the height of the line conductors shall be increased to provide sufficient clearance for safety in accordance with such use.

8. Line conductors crossing a public road or railway or crossing, or in proximity to or mounted on the same pole as other line conductors, telegraph wires, or metallic structures

(1) Where a line conductor crosses a public road or railway, or crosses over, or under, or is in proximity to any other line conductor, or telegraph wire, or any metal structure, precautions shall be taken to prevent danger so far as practicable, and also to prevent contact due to breakage or otherwise, between the line conductor and the other line conductor, telegraph wire, or metal structure.

(2) The precautionary means to be adopted shall be –

 (a) the use of conductors of ample mechanical strength, widely spaced cross arms, short spans, double or extra heavy cross arms, extra heavy metal pins or other metal insulator supports, extra heavy insulators, wires and poles properly supported and stayed, sufficient clearance between line conductors and metal structure, and, if required by the Director, wires terminated at each end of the span where the crossing occurs or where such line conductors are in proximity to any other line conductor, telegraph wire or metal structure;

 (b) the clearance between telegraph wires, and medium or low voltage line conductors, shall not, under conditions of maximum sag, be less than 2 feet:

Provided that where telegraph wires are not erected on the same pole as the medium or low voltage line conductors, the medium or low voltage line conductors shall be placed out of reach of a lineman who may be working on any part of a pole supporting such telegraph wires;

 (c) telegraph wires, when required to cross line conductors, shall be placed below them:

Provided that telegraph wires may be placed above medium or low voltage line conductors, provided the telegraph wires have a breaking load not less than 320 pounds, and they are efficiently protected by a covering of durable insulating material or by an earth wire run immediately above the said line conductors for the length of the span;

 (d) line conductors shall not be placed on the same cross arm with telegraph wires, neither shall high voltage line conductors be placed on the same cross arm as medium or low voltage line conductors;

 (e) where the line conductors forming part of systems at different voltages, or line conductors and telegraph wires are erected on the same pole, adequate provisions shall be made to guard against danger to linemen and from the lower voltage system or telegraph wires being charged above their normal voltage due to leakage from the higher voltage system;

 (f) any other means approved in writing by the Director.

9. Supports

Line conductors shall be attached to suitable insulators carried on supports of iron, steel or reinforced concrete, or, subject to the approval of the Director, on supports of wood. Special precautions shall be taken to prevent the corrosion of all metal work above, at and below the surface of the ground.

10. Strength of supports

(1) The supports, in conjunction with stays or struts, if provided, shall withstand without damage and without movement in the ground the longitudinal, transverse and vertical loads which occur. In no case shall the strength of a support in the direction of the overhead line be less than one-quarter the required strength in a direction transverse to the line.

(2) The following factors of safety shall apply to each support –

Material

Factor of Safety

Iron or steel

2.5

Wood

4.5

Reinforced concrete

3.5

(3) The factors of safety shall be calculated on the assumption that all line conductors, cables and wires carried by the supports are at a temperature of 50 degrees Fahrenheit, and that together with the supports they are subjected to a wind pressure of 20 pounds per square foot at right angles to the line, calculated on the whole of the projected area.

(4) The wind pressure on the lee side members of lattice steel or other compound structures, including A and H poles, shall be taken as one-half of the wind pressure on the windward side members.

(5) The factor of safety shall be calculated on the crippling load of struts and upon the elastic limit of tension members.

(6) –

11. Climbing on supports to be prevented

Adequate provisions, such as the use of tubular or rail poles erected so that the line conductors cannot be easily reached from any building, etc., or of anti-climbing spikes, shall be made to prevent unauthorised climbing of overhead line supports.

12. Factor of safety of steel or iron stay rods and stay wires

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