Section 6 Electrical and control equipment
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Ships, July 2022 - Part 7 Other Ship Types and Systems - Chapter 8 Positional Mooring and Thruster-Assisted Positional Mooring Systems - Section 6 Electrical and control equipment

Section 6 Electrical and control equipment

Parent topic: Chapter 8 Positional Mooring and Thruster-Assisted Positional Mooring Systems

6.1 General

6.1.1 The electrical installation is to be designed, constructed and installed in accordance with the relevant requirements of Pt 6, Ch 2 Electrical Engineering.

6.1.2 Control, alarm and safety systems are to be designed, constructed and installed, in accordance with the relevant requirements of Pt 6, Ch 1 Control Engineering Systems, together with the requirements of Pt 7, Ch 8, 6.2 Control stationsto Pt 7, Ch 8, 6.4 Controls.

6.2 Control stations

6.2.1 The operation of winches, windlasses and associated brakes, chainstoppers and pawls is to be controlled locally from weather-protected control stations which provide good visibility of the equipment and associated anchor handling operations.

6.2.2 A central control station, which may be located on the bridge or a separate manned control room, is to be provided from which brakes, chainstoppers and pawls can be remotely released.

6.2.3 For each anchor winch, the respective local control station is to be provided with a means of indicating the following:

  1. Line tension.

  2. Length of line paid out.

  3. Line speed.

6.2.4 The indication required by Pt 7, Ch 8, 6.2 Control stations 6.2.3 and Pt 7, Ch 8, 6.2 Control stations 6.2.3.(b) is to be repeated to the central control station and, in addition, a means of indicating the following is to be provided at this position:

  1. Mooring patterns and anchor line catenaries.

  2. Status of winch operation.

  3. Position and heading, see also Pt 7, Ch 8, 6.4 Controls 6.4.6.

  4. Gangway angle and extension, when applicable.

  5. Riser angle, when applicable.

  6. Wind speed and direction, see also Pt 7, Ch 8, 6.4 Controls 6.4.9.

6.2.5 Means of voice communication are to be provided between the central control station, each local control station and anchor handling vessels, when applicable.

6.3 Alarms

6.3.1 Alarms are to be provided at the local and central control stations for the following fault conditions:

  1. Excessive line tension.

  2. Loss of line tension.

  3. Excessive gangway angle and extension, when applicable.

  4. Excessive riser angle, when applicable.

6.3.2 Alarms are to be provided adjacent to the winches and windlasses to warn personnel prior to and during any remote operation.

6.3.3 Alarms are to be provided at the central control station for the following fault conditions:

  1. When the ship deviates from its predetermined area of operation.

  2. When the ship deviates from its predetermined heading limits.

These alarms are to be adjustable, but should not exceed specified limits. Arrangements are to be provided to fix and identify their set points.

6.4 Controls

6.4.1 Adequate controls are to be provided at the local control station for satisfactory operation of the winch(es).

6.4.2 The braking system is to be arranged so that the brakes, when applied, are not released in the event of a failure of the normal power supply.

6.4.3 Standby power is to be provided to enable winch brakes to be released within 15 seconds in an emergency. The release arrangements are to be operable locally at each winch and from the central control position, and are to be such that the entire anchor line can be lowered in a controlled manner.

6.4.4 The standby power is to be such that, during lowering of the anchor line, it is possible to apply the brakes once and then release them again in a controlled manner.

6.4.5 Standby power is to be provided, so that any anchor line stoppers or pawl mechanisms may be released from either the local or central control stations up to a line tension equal to the minimum rated break strength of the anchor line. These mechanisms are to be capable of release at the maximum angles of heel and trim under the damage stability and flooding conditions for which the ship is designed.

6.4.6 At least one position reference system and one gyrocompass or equivalent is to be provided, when applicable, to ensure the specified area of operation and heading deviation can be effectively monitored.

6.4.7 Position reference systems are to incorporate suitable position measurement techniques which may be by means of acoustic devices, radio, radar, taut wire, riser angle, gangway extension and angle or other acceptable means depending on the service conditions for which the ship is intended.

6.4.8 A vertical reference sensor is to be provided, if applicable, to measure the pitch and roll of the ship.

6.4.9 Means are to be provided to ascertain the wind speed and direction acting on the ship.

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