CAP. 103]
Electricity Supply.
[r. 39 cont.] being charged to any pressure beyond the limits of pressure
for which those mains are intended.
(14) In delivering the energy to a sub-station at extra high pressure the company shall exercise all due precautions so as to avoid risk of causing fire on the premises.
(15) All extra high pressure electric lines and apparatus placed in a sub-station shall be highly insulated and thoroughly protected against injury to the insulation or access of moisture, and any metal forming part of the electric circuit shall not, unless efficiently connected with earth, be exposed so that it can be inadvertently touched. All such lines shall be so fixed and protected as to prevent the possibility of electrical discharge to any adjacent metallic substance.
(16) The Director of Public Works shall be entitled to enter at all times any of the generating stations or sub-stations of the company supplying or supplied at an extra high pressure, and to make any such examination and tests of the mains, machines, transformers or other apparatus in use in those stations as may appear to him necessary, and the company shall afford all due facilities for examination and tests.
(17) Where any extra high pressure circuit is connected with earth the connection shall be made at one point only, namely at the generating station, sub-station or transformer, and the insulation of the circuit shall, except at that point, be efficiently maintained throughout.
(18) (a) The neutral point of the star winding of each distinct three-phase circuit, used for extra high pressure, may be connected with earth or may be insulated. If connected with earth through a resistance, that resistance shall be sufficiently low to ensure that the fuse or automatic circuit-breaker in the mains shall act.
(b) If the neutral point is not connected with earth a separate electro-static voltmeter placed in a conspicuous position in the generating station shall be connected between each circuit and earth; and if the indications of the voltmeters show that the insulation of any of the circuits is faulty, immediate steps shall be taken to restore the insulation.
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