Hong Kong Regulations

ELECTRICITY SUPPLY REGULATIONS - REGULATION 2

Pressure of supply to consumers

Caution: This is a past version. See the current version here.

GENERAL

The pressure of a supply delivered to any consumer shall not exceed the limit
of low pressure except for special purposes, for which a medium pressure
supply may be given on the consumer undertaking to comply with the following
conditions-

   (a)  where the supply is for power purposes-

        (i)    the frame of every electric motor shall be efficiently 
               connected with earth;

        (ii)   the consumer's wires forming the connections to motors, or
               otherwise in connection with the supply, shall be, as far as
               practicable, completely inclosed 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;

        (iii)  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
               connected 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;

        (iv)   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 inclosed 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;

        (v)    a notice shall be fixed in a conspicuous position at every
               motor and switch board in connection with the supply forbidding
               unauthorized persons to touch the motors or apparatus;

   (b)  where the supply is for arc lamps in series-

        (i)    the consumer's wires forming the connections to the arc lamps,
               or otherwise a connection with the supply, shall be, as far as
               practicable, completely inclosed 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;

        (ii)   the supply to every arc lamp 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 arc lighting, and
               connected so that by its means all pressure can be cut off from
               the arc lamp itself and from any regulating switch, resistance
               or other device in connection therewith: Provided that where
               the arc lamps are connected in series across the outer
               conductors of a three-wire system, it shall be sufficient if 1
               such switch be provided for each series of arc lamps;

        (iii)  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 inclosed 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 Electrical and Mechanical Services otherwise allows- (L.N.
        76 of 1982; L.N. 298 of 1982)

        (i)    the consumer's wires forming the connections to the
               incandescent lamps, or otherwise in connection with the supply,
               shall be completely inclosed in strong metal casing and this
               casing together with the switches and lamp holders, if
               metallic, shall be efficiently connected  with earth;

        (ii)   switches, efficient fuses or other automatic cut-out shall be
               provided, so as to protect the circuits from excess of current,
               and all switches and cut-outs shall be so inclosed 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 action;

   (d)  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 prescribe.