Electricity Supply.
Arc lighting.
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ground.
35. Arc lamps used in any street for public lighting shall be so fixed as not to be in any part at a less height than ten feet from the ground.
be guarded.
36. 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 in situations where there is any danger of the presence of explosive dust or gas.
Connexion of circuits with earth.
37. Where the pressure of a supply between the adjacent conductors of a three-wire system of mains exceeds 125 volts the intermediate conductor shall be connected with earth in accordance with the following conditions—
(a) the connexion with earth of the intermediate conductor shall be made at one point only on each distinct circuit, namely at the generating station, sub-station or transformer, and the insulation of the circuit shall be efficiently maintained at all other parts;
(b) the current from the intermediate conductor to earth shall be continuously recorded and if it at any time becomes excessive steps shall be immediately taken to improve the insulation of the system.
Connexion with earth of other circuits.
38. The company shall not connect any other circuit with earth except with the approval of the Director of Public Works and subject to such conditions as he may prescribe.
Extra high pressure.
regulations as to extra high pressure.
39. (1) This regulation shall have effect in the case of a supply at extra high pressure, and shall be in addition to and not in substitution for the obligations imposed by the foregoing regulations.
(2) An extra high pressure main shall not be brought into use unless, after it has been placed in position and before it is used for the purposes of supply, the insulation of every part thereof has withstood the continuous application, during half an hour, of pressure exceeding the maximum pressure to which it is intended to be subject in use, that is
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