Section 2 Electrical Equipment

201. Earthing of non-metallic craft

1. Non-metallic yachts are to comply with the following requirements.

(1) To minimize the risk of fire, structural damage, electrical shock and radio interference due to lightning strike or electrostatic discharge, all metal parts of the craft are to be bonded together, in so far as possible in consideration of galvanic corrosion between dissimilar metals, to form a continuous electrical system, suitable for the earth return of electrical equipment and to connect the craft to the water when water-borne. The bonding of isolated components inside the struc- ture is not generally necessary, except in fuel tanks.

(2) Each pressure fueling point is to be provided with a means of bonding the fueling equipment to the craft.

(3) Metallic pipes capable of generating electrostatic discharges, due to the flow of liquids and gas- es, are to be bonded so as to be electrically continuous throughout their length and they are to

be adequately earthed.

(4) Primary conductors for lightning discharge currents are to have a minimum cross section of 70

mm in copper, or an equivalent surge carrying capacity in aluminium.

(5) Secondary conductors provided for the equalization of static discharges, bonding of equipment, etc., but not for carrying lightning discharges, are to have a minimum cross section of 5 mm

copper or an equivalent surge current carrying capacity in aluminium.

(6) The electrical resistance between bonded objects and the basic structure is not to exceed 0.02 ohms except where it can be demonstrated that a higher resistance will not cause a hazard. The bonding part is to have sufficient cross-sectional area to carry the maximum current likely to be imposed on it without excessive voltage drop.

202. Emergency electrical equipment

1. The emergency source of electrical power in craft is to be capable of supplying simultaneously at least the following services for the periods specified, having regard for starting currents and the

transitory nature of certain loads, this requirement substitutes for Pt

if they depend upon an electrical source for their operation and

6, Ch 1, 1402. 2 of the Rules for Classification of Steel Ships.

(1) For a period of 12 hours, emergency lighting

(A) At the stowage positions of life-saving appliances.

(B) At all escape routes such as alleyways, stairways, exits from accommodation and spaces, embarkation points, etc.

(C) In the public spaces, if any.

service

(D) In the machinery spaces and main positions.

(E) In control stations.

(F) At the stowage positions for fireman's

(G) At the steering gear.

emergency generating spaces including their control

outfits, and

Pt 6 Electrical Equipment and Control Systems

Ch 1 Electrical Equipment Pt 6, Ch 1

(2) For a period of 12 hours

(A) The navigation lights and other lights required by the International Regulations for Preventing Collisions at Sea in force.

(B) Electrical internal communication equipment for announcements during evacuation.

(C) Fire detection and general alarm system and manual fire alarms, and

(D) Remote control devices of fire-extinguishing system, if electrical type.

(3) For a period of 4 hours of intermittent operation

(A) The daylight signalling lamps, if they have no independent supply from their own accumu- lator battery, and

(B) The craft‘s whistle, if electrically driven.

(4) For a period of 12 hours

(A) The navigational equipment as required by chapter 13 of HSC code. Where such provision

is unreasonable or impracticable, the Society may waive this requirement for yachts of less than 5,000 tons gross tonnage,

(B) Essential electrically powered instruments and controls for propulsion machinery, if alternate

sources of power are not available for such devices,

(C) One of the fire pumps required by Pt 7, Ch 2, 304. 1,

(D) The sprinkler pump and drencher pump, if fitted,

(E) The emergency bilge pump required by Pt 5 and all the equipment essential for the oper- ation of electrically powered remote controlled bilge valves, and

(F) Craft radio facilities and other loads as set out in 14.12.2 of HSC code.

(5) For a period of 10 minutes

Power drives for directional control devices including those required to direct thrust forward and astern, unless there is a manual alternative acceptable to the Society, in consideration of size, design, speed limitation or other necessary factor.

2. The emergency generator and its prime mover and any emergency accumulator battery are to be so designed and arranged as to ensure that they will function at full rated power when the craft is upright and when the craft has an expected list or trimming or is in any combination of angles within those limits.

3. As the substitute requirement for Pt 6, Ch 1, 1401. 2 of the Rules for Classification of Steel Ships, the emergency source of electrical power, associated transforming equipment, if any, transi- tional source of electrical power, emergency switchboard and emergency lighting switchboard are to be located above the waterline in the final condition of damage as referred to in chapter 2 of HSC code, operable in that condition and readily accessible. The location of the emergency source of electrical power, associated transforming equipment, if any, the transitional source of emergency power, the emergency switchboard and the emergency electrical lighting switchboards in relation to the main source of electrical power, associated transforming equipment, if any, and the main switchboard are to be such as to ensure that a fire or other casualty in spaces containing main source of electrical power, associated transforming equipment, if any, and the main switchboard or in any machinery space will not interfere with the supply, control and distribution of emergency electrical power.

4. Where the main source of electrical power is located in two or more compartments which are not contiguous, each of which has its own self-contained systems, including power distribution and con- trol systems, completely independent of each other and such that a fire or other casualty in any one of the spaces will not affect the power distribution from the others, or to the services required

by Par 1, the

requirements of Par 3 and Pt 6, Ch 1, 1401. 1 and 4 of the Rules for

Classification of Steel Ships may be considered as met without an additional emergency source of

electrical power,

provided that

(1) There is at least one generating set, meeting the requirements of Par 2 above and each with sufficient capacity to meet the requirements of Par 1, in each of at least two non-contiguous spaces,

(2) The arrangements required by (1) above in each such space are to be equivalent to those re- quired by Pt 6, Ch 1, 1403. (1), 1405. and 1406. 1 to 3 of the Rules for Classification of Steel Ships so that a source of electrical power is available at all times to the services required by Par 1, and

(3) The generator sets referred to in (1) above and their self-contained systems are to be installed so as to maintain operation condition even if any one space is damaged or flooded.

150 Guidance for Large Yachts 2014

203. Stabilization system of craft

1. Where stabilization system of a craft is essentially dependent on one device as with a single rudder or pylon, which is itself dependent on the continuous availability of electric power, it should be served by at least two independent circuits, one of which is to be fed either from the emergency source of electric power or from an independent power source located in such a position as to be unaffected by fire or flooding affecting the main source of power. Failure of either supply is not to cause any risk to the craft or passengers during switching to the alternative supply. These circuits are to be provided with short circuit protection and an overload alarm.

2. Protection against excess current may be provided, in which case it is to be for not less than twice the full load current of the motor or circuit so protected, and is to be arranged to accept the ap- propriate starting current with a reasonable margin. Where three-phase supply is used, an alarm is to be provided in a readily observed position in the craft's operating compartment that will indicate failure of any one of the phases.

3. Where such systems are not essentially dependent on the continuous availability of electric power but at least one alternative system, not dependent on the electric supply is installed, then the elec- trically powered or controlled system may be fed by a single circuit protected in accordance with Par 2.

4. Stabilization system of craft (hereinafter refer to as "stabilization system") it is to be complied with as following requirements;

(1) Definition

(A) "Stabilization control system" is a system intended to stabilize the main parameters of the crafts attitude : heel, trim, course and height and control the yacht's motions : roll, pitch, yaw and heave. This term excludes devices not associated with the safe operation of the yacht, e.g. motion reduction or ride control systems in order to improve a great convenience.

The main elements of a stabilization control system may include the following.

(a) devices such as rudders, foils, flaps, skirts, fans, water jets, tilting and steerable pro- pellers, pumps for moving fluid, etc.

(b) power drives actuating stabilization devices ; and

(c)

stabilization equipment for accumulating and processing data for making decisions and giving commands such as sensors, logic processors and automatic safety control.

(B) "Self-stabilization" is stabilization ensured solely by the yacht's inherent characteristics.

(C) "Forced stabilization" is stabilization achieved by

(a)

an automatic control system ; or

(b) a manually control assisted system ; or

(c)

a combined system incorporating elements of both automatic and manually assisted con- trol systems

(D) "Augmented stabilization" is a combined of self-stabilization and forced stabilization.

(E) "Stabilization device" means a device as given in (A) (a) with the aid of which forces for controlling the yacht's position are generated.

(F) "Automatic safety control" is a logic unit for processing data and making decisions to

put the craft into the displacement or other safe mode if a condition impairing safety arises.

(2) Lateral and height control systems

(A) Yacht with an automatic control system should be provided with an automatic safety control

plan. Probable malfunctions should have only minor effects on automatic control system op- eration and should be capable of being readily counteracted by the operating crew.

(B) The parameters and levels at which any automatic control system gives the command to de-

crease speed and put the craft safety into the displacement or other safe mode should take account of the safety level and of the safe values of motions appropriate to the particular craft and service.

(3) Performance verification

(A) The limits of safe use of any of the stabilization control system devices should be based on demonstration and verification process in accordance with HSC Code 16.4.1

(B) Demonstration in accordance with HSC Code 16.4.1 should determine any adverse effects upon safe operation of the yacht in the event of an uncontrollable total deflection of any

one control device. Any limitation on the operation of the yacht as may be necessary to en-

sure that the redundancy or safeguards in the systems provide equivalent safety should be included in the craft operating manual.

Pt 6 Electrical Equipment and Control Systems

Ch 2 Control Systems Pt 6, Ch 2