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ELECTRICAL INSTALLATIONS





ELECTRICAL INSTALLATIONS
General
      (1)        In every ship the electrical installation shall be such that –
(a)   all electrical auxiliary services necessary for maintaining the ship in normal operational and habitable conditions will be ensured without recourse to the emergency source of electrical power; and
(b)   the electrical services essential for safety will be ensured under emergency conditions.
(2)            The electrical equipment and installations, including any electrical means of propulsion, shall be such that the ship and all persons on board are protected against electrical hazards.

Main source of electrical power and main switchboard
     (1)        Every ship in which electrical power is the only power for maintaining auxiliary services essential for the propulsion or safety of the ship shall be provided with two or more generating sets of such power that these services can be operated when any one of the sets is out of service.
(2)            Load shedding or other equivalent arrangements shall be provided to protect the generators required by subregulation (1) against sustained overload.
Additional requirements for ships constructed on or after 1 September 1984
(3)   (a)  A main source of electrical power shall be provided in every such ship with sufficient capacity to supply all the services required by regulation 48(1)(a) and (b) and this main source of electrical power shall consist of at least two generating sets.
(b)   The main source of electrical power shall be arranged so that such services can be maintained regardless of the speed and direction of rotation of the propulsion machinery or shafting.
(4)            The arrangement of the generating sets required by subregulation (3) shall be such that with any one of the sets out of service –
(a)   normal operational conditions of propulsion and safety of the ship and minimum comfortable conditions of habitability including those for cooking, heating, domestic refrigeration, mechanical ventilation, sanitary and fresh water can be maintained; and
(b)   from a dead ship condition, the remaining sets are capable of providing the electrical services necessary to start the main propulsion plant and the emergency source of electrical power may be used for this purpose if it is capable of simultaneously supplying the emergency supplies required by Part 3 in the Twelfth Schedule, or it is capable of supplying such services when combined with any other source of electrical power.
(5)            Any transforming equipment supplying an electrical system referred to in this regulation shall be arranged to ensure the same continuity of supply as that required for generating sets by this regulation.
(6)   (a)  The main switchboard shall be located in the same main fire zone and watertight compartment as the main generating sets in any ship with only one generating station.

(b)   Where there is more than one generating station and only one main switchboard, that switchboard shall be located in the same main fire zone and watertight compartment as one of the generating stations.

(c)   The Administration may permit other arrangements where other essential features of the ship render the application of this requirement impracticable subject to such alternative provisions as it may require.

(d)   For the purposes of this subregulation an environmental enclosure for the main switchboard such as a machinery control room within the main boundary of the space, does not provide separation between the generating sets and switchboards.

(7)   (a)  The main busbars shall be subdivided in every ship in which the total installed electrical power of the main generating sets exceeds 3 megawatt.
(b)   Each section of the busbars shall be interconnected by removable links or other suitable means such that the main generating sets and any supplies to duplicated services which are directly connected to the busbars are, so far as it is practicable, equally divided between the sections.
(c)   The Administration may permit other arrangements which provide equivalent system redundancy.
Additional requirements for ships constructed on or after 1 July 1998
(8)   (a)  Where the main source of electrical power is necessary for propulsion and steering of the ship, the system shall be so arranged that the electrical supply to equipment necessary for propulsion and steering and to ensure safety of the ship will be maintained or immediately restored in the case of loss of any one of the generators in service.
(b)   Where the main source of electrical power is necessary for propulsion of the ship, the main busbar shall be subdivided into at least two parts which shall normally be connected by circuit breakers or other approved means and so far as is practicable, the connection of generating sets and other duplicated equipment shall be equally divided between the parts.
(9)            A ship complying with subregulation (8) need not comply with subregulation (7).
Requirements for ships constructed on or after 1st September 1984

Lighting systems
     (1)        The main source of electrical power in every ship shall be capable of illuminating any part of the ship normally accessible to and used by the passengers or the crew.
(2)            The emergency electric lighting shall be arranged so that a fire or other casualty in spaces containing the emergency source of electrical power, the associated transformers, if any, the emergency switchboard and the emergency lighting switchboard will not render inoperative the main electric lighting system as required by subregulation (1).
(3)            Lighting fittings shall be arranged to prevent rises in temperature which would be damaging to the fitting or the electric wiring or which would result in a risk of fire.
Emergency and transitional sources of electrical power and emergency switchboards
53.       (1)        Every ship shall be provided, in a position above the uppermost continuous deck and outside the machinery casings, with a self-contained emergency source of electrical power so arranged as to ensure its functioning in the event of fire or other casualty causing failure of the main electrical installation.
(2)            The emergency and transitional source of electrical power and emergency switchboards shall be in accordance with the provisions of the Twelfth Schedule.
Additional requirements for ships constructed on or after 1 July 1998
(3)            Where electrical power is necessary to restore propulsion, the capacity shall be sufficient to restore propulsion to the ship in conjunction with other machinery, as appropriate, from a dead ship condition within 30 minutes after blackout.
Requirements for ships constructed on or after 1 September 1984

Location and construction of cables
54.   (1)   (a)  All electrical cables external to equipment shall be flame retardant and shall be installed so that their flame retarding or equivalent properties are not impaired.
(b)   The Administration may permit installation of cables which do not comply with the foregoing for particular purposes, such as radio frequency cables, where compliance would be impracticable.
(2)            Cables shall be installed and supported in such a manner as to avoid chafing and other damage and all metal sheaths and metal armour of electric cables shall be electrically continuous and shall be earthed except that the Administration may permit such earthing to be omitted for particular purposes.
(3)            Cables serving emergency services shall not, so far as is practicable, be routed through galleys, laundries, machinery spaces of Category A and their casings or other high risk areas except insofar as it is necessary to provide emergency services in such areas and cables connecting fire pumps to the emergency switchboard shall be of a fire resistant type where they pass through high fire risk areas.
(4)            Cables serving emergency services shall, where practicable, be installed in such a manner as to preclude them being rendered unserviceable by the effect of a fire in an adjacent space and subsequent heating of the dividing bulkhead.
(5)            The electrical, mechanical, flame retarding and, where applicable, fire resisting properties of the terminations and joints in any conductor shall be at least equivalent to those of the conductor.
Requirements for ships constructed on or after 26 May 1965

General precautions against shock, fire and other hazards

.       In every ship all electrical equipment shall be constructed and installed so that it will not cause injury when handled or touched in a proper manner. The precautions to be taken shall at least be in accordance with those set out in the Thirteenth Schedule.
Requirements for ships constructed on or after 1st September 1984

Electrical equipment in hazardous areas and spaces

      Electrical equipment shall not be installed in any hazardous area except in accordance with the requirements set out in the Fourteenth Schedule.


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1 comments:

Switchboard upgrades Brisbane said...

Electricity needs a little care. So, we have to hire licensed commercial & domestic electricians, local industrial electricians for electricity. Along with of that, we have to use good Quality of products of electricity, as well.

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