Marine cable, also known as marine power cable, is a kind of wire and cable used for power, lighting and general control of various ships and offshore oil platforms in rivers and seas.
Main application: It is used for power, lighting and general control of various ships in rivers and seas, offshore oil platforms and other water buildings. The executive standard is the executive standard of marine power cable: IEC60092-350 IEC60092-353 or GB9331-88.
The main parameters of marine power cable include model, specification, number, combustion characteristics, rated voltage, temperature, nominal sectional area, etc.
Marine cables can be divided into the following categories according to their applications:
1. Cables for lighting and power circuits.
2. Cables for control and communication loops.
3. Cable for telephone loop.
4. Cables for distribution boards.
5. Cables for mobile equipment.
6. Cables for internal wiring of control equipment.
7. Cables for other special devices.
Steps and principles for cable selection:
The selection steps and principles of cables in the ship’s power system are as follows:
1. Select the appropriate cable model according to the purpose, laying position and working conditions of the cable.
2. Select appropriate cable section according to equipment working system, power supply type, cable core and load current.
3. According to the calculation results of the system short circuit current, whether the short circuit capacity of a piece of cable meets the requirements.
4. Correct the rated current carrying capacity of the cable according to the ambient temperature, and then judge whether the allowable current of the cable is greater than the load current.
5. According to the correction factor of bundle laying, the rated current carrying capacity of the cable is corrected, and then it is judged whether the allowable current of the cable is greater than the load current.
6. Check the line voltage drop and judge whether the line voltage drop is less than the specified value.
7. Judge whether the cable is coordinated with the protection device according to the setting value of the protection device; In case of incongruity, judge whether the appropriate protective device or setting value can be changed; otherwise, select the appropriate cable load surface again.
There are many kinds of marine cables, so we should pay attention to the matching cables when selecting them, otherwise it is easy to cause great danger. When selecting cables, pay attention to the following principles: according to the use, this is generally used to distinguish power, lighting and radio communication; When selecting according to the laying position, environmental factors should be considered, such as the dryness and humidity of the air, the high and low temperature and shielding requirements; When selecting according to the working conditions, it is necessary to consider many requirements such as location, number of pipes to be threaded and whether they can be moved.
Post time: Oct-25-2022