PUBLIC RECORD OFFICE
Reference :-
THCO. 882
9
PUBLIC RECORD OFFICE, LONDON
ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC-
COPYRIGHT PHOTOGRAPH—NOT TO
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3,000 volts, the supply shall be deemed a high pressure supply; and (d.) Where the conditions of the supply are such that the pressure exceeds 3,000 volts, the supply shall be deemed an extra high pressure supply. Where these regulations require any metallic body to be "efficiently connected with earth." it shall be connected with the general mass of earth in such manner as will ensure at all times an immediate and safe discharge of electrical energy.
tieneral.
consumere.
2. The pressure of a supply delivered to any consumer Pressure of shall not exceed the limit of low pressure, except for supply to special purposes, for which a medium pressure supply may be given on the consumer undertaking to comply with the following conditions :--
(4.) Where the supply is for power purposes-
(1.) The frame of every electric motor shall be
efficiently connected with earth.
(2.) The consumer's wires forming the connections to motors, or otherwise in connection with the supply, shall be, as far as practicable, completely enclosed in strong metal casing efficiently connected with earth, or they shall be fixed in such a manner that there shall be no danger of any shock.
(3.) The supply to every motor shall be controlled by means of an efficient cut-off switch, placed in such a position as to be easily handled by the person in charge of the motor, and con nected so that by its means all pressure can be cut off from the motor itself, and from any regulating switch, resistance or other device in connection therewith.
(4.) Switches, efficient fuses or other automatic circuit-breakers shall be provided, so as to protect the circuits from excess of current, and all switches and cut-outs shall be so enclosed and protected that there shall be no danger of any shock being obtained in the ordinary handling thereof, or of any fire being caused by their normal or abnormal action. (5.) A notice shall be fixed in a conspicuous position at every motor and switch board in connection with the supply forbidding un- authorised persons to touch the motors or apparatus.
(b) Where the supply is for arc lamps in series-
(1.) The consumer's wires forming the connections to the arc lamps, or otherwise in connection with the supply, shall be, as far as practicable, completely enclosed in strong metal casing efficiently connected with earth, or they shall be fixed in such a manner that there shall be no danger of any shock.
(2.) The supply to every arc lamp shall be con- trolled by means of an efficient cut-off switch, placed in such a position as to be easily handled by the person in charge of the arc lighting, and connected so that by its means
Introduc-
tion of
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all pressure can be cut off from the arc lamp itself, and from any regulating switch, resist- ance or other device in connection therewith. Provided that where the arc lamps are con. nected in series across the outer conductors of a three-wire system, it shall be sufficient if one such switch be provided for each series of are lamps.
(3.) Switches, efficient fuses or other automatic cut-outs shall be provided, so as to protect the circuits from excess of current, and all switches and cut-outs shall be so enclosed and protected that there shall be no danger of any shock being obtained in the ordinary handling thereof, or of any fire being caused by their normal or abnormal action.
(c.) Where the supply is for incandescent lamps in series, [unless the Director of Public Works other. wise allows,]-
(1.) The consumer's wires forming the connections
to the incandescent lamps, or otherwise in connection with the supply, shall be com- pletely enclosed in strong metal casing an this casing together with the switches and lamp holders, if metallic, shall be efficiently connected with earth.
(2.) Switches, efficient fuses or other automatic cut-outs shall be provided, so as to protect the circuits from excess of current, and all switches and cut-outs shall be so enclosed and protected that there shall be no danger of any shock being obtained in the ordinary handling thereof, or of any fire being caused by their normal or abnormal action.
Where the supply is for any special purpose other than those above-mentioned, or where the pressure of the supply exceeds the limits of medium pressure it shall be subject to such other regulations as the Governor in Council may from time to time prescribe.
3. When the pressure between the outer conductors of three-wire a three-wire system exceeds 250 volts and the three wires system into of the system or two pairs of wires are brought into a consumer's consumer's premises, the supply shall be given to two pairs
premises.
Minimum
sise of
conductors.
Insulation
and
medium
of terminals arranged in such a manner that there shall be no danger of any shock, and the wiring from those terminals shall be kept distinct.
4. The sectional area of the conductor in any electric line laid or erected in any street after the date of these regulations shall not be less than that of a strand of seven wires, each of which is of No. 20 standard wire gauge, and the sectional area of every wire in a strand forming any such conductor shall not be less than that'
This regulation shall not apply in the case of an electric line placed in a lamp-post.
gauge.
5. Every low pressure and medium pressure main chall test of low be tested for insulation after having been placed in position premare and before it is used for the purposes of supply, the testing pressure being the maximum pressure to which it is intended to be subjected in use, and in any case at least 200 volts, and the company shall duly record the results of the tests of each main, or section of a main.
pressure
mains.
لله يام الرسة في لي