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ship electrical standards...distribution

11.1 In passenger ships, distribution systems shall be so arranged that fire in any main fire zone will not interfere with essential services in any other main fire zone.

11.2 The requirement of subsection 11.1 is met if the main and emergency feeders passing through any zone are separated both vertically and horizontally as widely as is practicable.

11.3 If, in any passenger ship, two or more generating sets can be in operation at the same time for maintaining the auxiliary services essential for the propulsion or safety of the ship:

1. provision shall be made for the sets to operate in parallel; and


2. means shall be provided so that in the event of overload or a partial failure of the supply, the services not essential to the propulsion and safety of the ship will be cut out first, the services essential for those purposes being retained in circuit with such of the generators as may remain in service.

11.4 Distribution systems employing a single wire with hull return shall not be used for power, heating or lighting; this does not preclude the use of impressed current cathodic protective systems, limited and locally grounded systems, or insulation level monitoring devices where the circulating current is less than 30 mA.

11.5 Every current-consuming appliance shall be connected to either:

1. a main switchboard;


2. an emergency switchboard;


3. a distribution centre; or


4. a panelboard;

11.6 Each branch circuit shall be protected against short-circuit and, subject to subsection 11.10, shall also be protected against overload.

11.7 Each branch circuit operating at voltages of 55 volts or over shall be provided with a switch or circuit breaker with a pole for each conductor; any switch or circuit breaker fitted shall operate simultaneously in the grounded conductor and the insulated conductor.

11.8 No fuse, non-linked switch or non-linked circuit breaker shall be inserted in a grounded conductor.

11.9 Each circuit shall be permanently indicated together with the rating or setting of the appropriate overload protective device.

11.10 Where the steering gear is operated by two independent electrically powered mechanisms and an approved alternative means of steering is not provided, two independent sets of supply cables shall be provided which shall be:

1. connected to the main switchboard, except that where there is an emergency generator, one set shall be connected to the main switchboard via the emergency switchboard, in accordance with the requirements of the Marine Machinery Regulations Schedule (VII),


2. Separated throughout their length as widely as practicable,


3. Together with the motors, protected by fuses, circuit breakers or other similar devices against short-circuit; no other overload device or fuse that will open the steering motor power circuit is to be provided in the motor control circuit and the steering control circuits to the bridge; and



4. Short circuit protection only shall be provided for the control circuits of the bridge steering control systems; the protection shall be instantaneous and rated at 300 percent of the current carrying capacity of the smallest control system conductor.

11.11 Each steering gear motor starter shall be equipped with a thermal overcurrent relay that shall operate an alarm when the motor is overloaded.

11.12 Each steering gear motor is to be provided with the following monitoring devices at the main machinery control position and at the steering control station on the bridge:

1. running and stop indication for each steering gear motor;


2. audible alarm and visual lamp indication for the following:
   
   
   
   1. overcurrent,
   
   
   2. main power supply failure;
   
   
   
   3. control power failure;
   
   
   4. where a steering gear hydraulic fluid reservoir is fitted it shall be provided with a low level alarm,
   
   
   5. phase failure alarm on the load side of the starter.
   
   


3. dimming devices may be fitted in accordance with section 3 (23),


4. remote steering control stations shall include items (a) and (b); the audible device may be omitted if the bridge alarm can be heard at the remote steering positions.

11.13 The supply for each steering gear remote control system shall have its own individual circuit supplied from the respective steering gear power circuit, or directly from the switchboard busbars adjacent to the steering gear power circuit in addition the steering gear power circuit shall also supply each of the monitoring devices required in Section 11.12 (a) and (b).

11.14 Where the steering gear is electrically operated by remote control from the bridge, or from other remote steering control stations there shall be provided two independent electric control systems.

11.15 Where fitted, “jog” steering control handles shall be of a type that requires a positive action to initiate operation.

11.16 The control of each steering gear motor is to be such that the motor will restart automatically upon restoration of voltage after a power failure.

11.17 Means shall be provided to effectively communicate between the bridge and steering gear compartment.

11.18 Steering gear motors are to be controlled from the bridge, the steering gear compartment; control may also be provided at other control stations; however when control from more than one position is provided, the over-riding control shall be at the bridge while the vessel is under way.

11.19 Machinery space ventilation fans, boiler fans, fuel oil transfer pumps, fuel oil pressure pumps and lube oil transfer and purifiers shall be provided with a means for stopping from a position outside the machinery space which will always be accessible in the event of fire in the space, in passenger vessels the accommodation and vehicular ventilation fans shall be provided with a means of stopping and motor indication at the main fire control station.

11.20 The emergency means for stopping machinery space ventilation fans, accommodation ventilation fans and vehicular space ventilation fans shall be separate and completely independent of each other.

11.21 The means provided for remote stopping of the electrical equipment required by subsection 11.19 shall be so arranged that a separate power source is not required to accomplish remote emergency stopping; the source of power provided in order to accomplish remote emergency stopping shall be:

1. provided from each individual motor control circuit; or


2. from a dedicated source of power feeding an individual motor, or group of motors connected to a motor control centre for a particular space, shunt trip arrangements shall not be permitted.

11.22 The activation of a remote emergency stop circuit, manually initiated, shall continue until it is manually reset.

11.23 Together with the manually initiated stopping devices for the galley ventilation fans located in the galley, the range/fryer gas smothering system shall also initiate a galley ventilation shut down

11.24 Where refrigerated lockers of the walk-in type can be locked so that they cannot be opened from inside, a “locked-in” alarm system shall be provided and shall comprise:

1. an on-off switch located inside at the exit of each such space,


2. a visual and audible alarm located in the galley or other space where persons are normally present or employed; and


3. a nameplate for both the actuator and the alarm to designate the function.

11.25 A branch circuit having a current rating not exceeding 15 amps may supply any number of lighting points; the total connected load of the sub-circuit shall not exceed 80% of the set current of the final sub-circuit protective device unless the final sub-circuit protective device is certified and marked for continuous operation at 100% of its rating.

11.26 When the total connected load is not known, a branch circuit having a current rating not exceeding 15 amps may supply any number of lighting points up to the following maxima:

1. at voltages up to and including 50V-10 points;


2. from 51V up to and including 130V-14 points; or


3. from 131V up to and including 230V-18 points.

11.27 A branch circuit of rating exceeding 20 amperes is not to supply more than one point.

11.28 Where two or more distribution panels or panel-boards are connected to a cable and the cable is looped from board to board without passing through a protective device, the cable conductors shall be of the same cross-sectional area throughout except where the length between panels is less than 2 metres.

11.29 Where an automatic sprinkler system is installed in accordance with the Fire Detection and Extinguishing Equipment Regulations:

1. there shall be not less than two independent sources of power supply for the sprinkler seawater pump and automatic alarm and detection system,


2. one supply for the pump shall be taken from the main switchboard and one from the emergency switchboard by separate feeders reserved solely for that purpose,


3. the feeders shall be arranged so as to avoid galleys, machinery spaces and other enclosed spaces of high fire risk except insofar as it is necessary to reach the appropriate switchboards and shall be run to an automatic change-over switch situated near the sprinkler pump; this switch shall permit the supply of power from the main switchboard so long as a supply is available therefrom and be so designed that, upon failure of that supply, it will automatically change-over to the supply from the emergency switchboard;



4. the switches on the main switchboard and the emergency switchboard shall be clearly labelled and normally kept closed; no other switch shall be permitted in the feeders concerned; and


5. one of the sources of power supply for the alarm and detection system shall be an emergency source.

11.30 Where an automatic fire alarm and fire detection system is required the system shall be in accordance with Section 21.6.

11.31 Separate branch circuits shall be provided for every motor required for an essential service and for every motor rated at 1.25 kW or more.

11.32 Lighting circuits shall be supplied by branch circuits separate from those for heating and for power requirements; this does not preclude the supply from lighting circuits of cabin ventilating fans, wardrobe heaters, anti-condensation heaters or small power consumers up to 600 watts.

11.33 If a ship is divided into fire zones, at least two separate circuits for lighting shall be provided in each zone, one of which may be the circuit for the emergency lighting.

11.34 A lighting circuit in a bunker or hold shall be provided with an isolating switch and visual indication outside the space which shall be accessible only to authorized personnel and provision shall be made for the complete isolation and locking in the “off” position of the means of control of every such circuit.

11.35 Electric lighting in main propelling machinery spaces, other large machinery spaces and on passenger ships, in alleyways and stairways leading to boat decks and in public rooms shall be supplied from at least two final sub-circuits, one of which may be the emergency circuit, in such a way that failure of any one of the circuits does not reduce the lighting to an inadequate level; lighting circuits shall be arranged so as to provide an adequate level of illumination on the fronts of switchboards and control panels; circuits and fittings for this purpose may form an integral part of the switchboard or control panel.

11.36 Where single-phase ac branch circuits are connected into three-phase or three-phase, 4-wire or single-phase, 3-wire distribution panels, the circuits shall be so disposed that the load will be balanced within 15% at the individual distribution panel; for dc branch circuits connected into 3 wire dc distribution panels, the circuits shall be similarly arranged.

11.37 Navigation lights shall be connected by means of a length of heavy duty flexible cable to a watertight receptacle outlet located adjacent thereto and each lamp shall be connected to it’s branch circuit conductors by means of an individual heavy duty portable cable and a watertight receptacle plug or may be wired direct:

1. electric side, masthead, anchor and stern lights shall be controlled by an indicator panel located in an accessible position under the control of the officer of the watch;


2. each such light shall be controlled and protected in each insulated pole by a switch and fuses or circuit breaker mounted on the indicator panel referred to in paragraph (a),


3. each such light shall be provided with an automatic indicator which gives aural or visual warning, or both, in the event of extinction of the light and if:
   
   
   
   1. an aural device alone is used, shall be connected to a separate source of supply; or
   
   
   2. a visual signal is used which is connected in series with the light, means shall be provided to prevent the extinction of the light due to the failure of the visual signal,
   
   
   
   3. on small vessels where the condition of the navigation light can be observed from the manoeuvring position automatic failure of the lamp indicator need not be fitted.
   
   


4. for vessels 15 metres or greater the indication light panel shall be provided with a means to transfer a navigation light to the respective alternate lamp by means of a suitable selector switch located in the indicator panel;


5. provision shall be made on the bridge to select an alternative main supply circuit by means of a transfer switch located at the indicator panel,


6. the feeders supplying a navigation light panel shall be protected by over-current devices rated or set at not less than twice the rating of the line protection in the navigation light panel: the navigation panel shall be fitted with main over-current devices rated or set greater than the maximum load including spares of the panel for each feeder and with branch protection rated or set at not less than 3 amperes in each conductor, for voltages under 55 volts refer to section 51.7; and


7. the period of time required for the alternate supply to the navigation lights control panel shall be in accordance with the applicable group in Schedule 1.

11.38 The wiring between the indicator panel and the watertight duplex receptacle at the side, masthead, anchor and stern lights shall be in duplicate and may be either two, 2-conductor cables or one 4-conductor cable.

11.39 Where arrangements are made for the supply of electric power from an external source on shore or elsewhere, a suitable connection box shall be installed in a position in the ship suitable for the convenient reception of flexible cables from the external source, having terminals of ample size and suitable shape to facilitate a satisfactory connection:

1. except for single-phase shore power arrangements fitted in accordance with paragraph (e), all shore power connections shall be provided with a ground connection terminal for connecting the vessel’s hull to the shore ground,


2. the shore connection shall be provided with an indicator at the main switchboard in order to show when the cable is energized,


3. means shall be provided for checking the polarity for dc and single-phase ac systems and the phase sequence for three-phase ac of the incoming supply in relation to the ship’s system; and


4. bolts, nuts and washers used to maintain contact on bus and connection bars shall be of non-ferrous material or of steel rendered corrosion-resistant by zinc-electroplating or an equivalent process,


5. for vessels that may experience excessive induced electrolysis as a result of a shore power installation fitted in accordance with paragraph (a), an alternative shore power connection arrangement may be fitted as follows:
   
   
   
   1. provided with an isolating transformer that has the transformer case electrically isolated from the transformer core,
   
   
   
   2. the isolating transformer case grounded to the vessel’s hull or to the continuous ground conductor for vessels constructed of wood or composite materials,
   
   
   3. the exterior of the shore power cable connection plug on the vessel must be effectively encapsulated and insulated; and
   
   
   4. a series of sketches, depicted in figures 11-1 and 11-2 are provided for reference.
   
   

11.40 Vessels that utilize a grounded distribution system are to be provided with a suitable means to prevent the flow of load current through the hull or the grounding hardware while connected to shore power facilities.

11.41 Transformers for power and lighting shall be protected in accordance with Section 26, Part I of the Canadian Electrical Code.

11.42 Automatic changeover switches, relays and circuit breakers shall not be operated by a separate, remote or auxiliary power source.

11.43 Magnetic switches used for automatic bus transfer shall be of the latched type with coils energized only at the moment of operation.

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