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THE HONGKONG GOVERNMENT GAZETTE, MAY 19, 1911.
Introduc tion of three-wire system into consumer's premises.
Minimum size of conductors.
Insulation
test of low
medium
(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. (e.) Where the supply is for incandescent lamps in series, unless the Director of Public Works otherwise allows,-
(1.) The consumer's wires forming the connec- tions to the incandescent lamps, or otherwise in connection with the supply, shall be com- pletely enclosed in strong metal casing and 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 a three-wire system exceeds 250 volts and the three wires of the system or two pairs of wires are brought into a consumer's premises, the supply shall be given to two pairs of terininals 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 other than low tension 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. 22 standard wire gauge, and the sectional area of every wire in a strand forming any such conductor shall not be less than that gauge, and where such stranded conductor is erected it shall be suspended from a suitable bearer wire. In the case of low tension conductors in any elec tric line the sectional area shall not be less than that of a single wire of No. 16 standard wire gauge efficiently insulated.
This regulation shall not apply in the case of an electric line placed in a lamp-post.
5. Every low pressure and medium pressure main, after having been placed in position, and before it is used pressure and for the purposes of supply, shall withstand a pressure equal to the maximum pressure to which it is intended to be subjected in use, and in any case at least 200 võlts, and further, before being used as aforesaid, it shall be tested for insulation, and the company shall duly record the results of the tests of each main or section of a main.
pressure mains.
Testing of insulation of all parts of high pressure
circuit.
Mainten- ance of insulation.
6. A high pressure circuit shall not be brought into use unless the insulation of every part thereof has with- stood the continuous application, during one hour, in the case of every electric line, of a pressure equal to the full working pressure to which it is intended to be subjected in use, and, in the case of every machine, device, or apparatus, of a pressure equal to the full working pressure to which it is intended to be subjected. The company shall duly record the results of each test.
7. There shall be maintained by the company at each station or sub-station as may be necessary a leakage. indicator of approved pattern and so arranged that the leakage on each main feeder can be readily ascertained at any time and a weekly test recorded. If at any time
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