Year: 20XX Language: English Author: Antwerp Maritime Academy Genre: Guide Publisher: Antwerp Maritime Academy Format: PDF Quality: eBook Pages count: 159 Description: Important considerations in marine electrical installations Marine installations almost always have a floating ground (Isolated neutral or high impedance earthing). We have to take into consideration the vibrations on a ship. Technical spaces can be very small. The temperature is most of the time high but can also be very cold. We can have a humidity of near to 100 pro cent. A ship is completely constructed out of steel which is a excellent conductor for electricity and heat. An electrical network in ship application is called an island network or isolated network meaning that the electrical power is generated, distributed and consumed in a closed area, the ship. If failure occurs in the island network only consumers connected to that network suffer the consequences. The exception is the shore to ship connection. Shore to ship arrangements will increase in the future due to stricter port emission rules. Figure 2: Low voltage cable tray Why High Voltage on Board of Ships As the demand for electrical power increases on vessels the supply current ratings becomes too high for the usual 3 phase 440 V. To reduce the size of both steady state and fault current levels it is necessary to specify a higher power system voltage at the higher power ratings. In marine practice voltages below 1000 V are considered LV (low voltage). HV (high voltage) is any voltage above 1 KV. Typical marine HV system voltages are 3.3 KV and 6.6 KV. 11 KV Systems are emerging with the still increasing power demands. Low voltage side of the network the voltage levels are 440V, or 680V. By generating electrical power at 6.6 KV instead of 440 V the distribution and switching of power levels above about 6 MW becomes more practicable and manageable.
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High Voltage Safety
Language: English
Author: Antwerp Maritime Academy
Genre: Guide
Publisher: Antwerp Maritime Academy
Format: PDF
Quality: eBook
Pages count: 159
Description: Important considerations in marine electrical installations Marine installations almost always have a floating ground (Isolated neutral or high impedance earthing). We have to take into consideration the vibrations on a ship. Technical spaces can be very small. The temperature is most of the time high but can also be very cold.
We can have a humidity of near to 100 pro cent. A ship is completely constructed out of steel which is a excellent conductor for electricity and heat. An electrical network in ship application is called an island network or isolated network meaning that the electrical power is generated, distributed and consumed in a closed area, the ship. If failure occurs in the island network only consumers connected to that network suffer the consequences. The exception is the shore to ship connection.
Shore to ship arrangements will increase in the future due to stricter port emission rules. Figure 2: Low voltage cable tray Why High Voltage on Board of Ships As the demand for electrical power increases on vessels the supply current ratings becomes too high for the usual 3 phase 440 V. To reduce the size of both steady state and fault current levels it is necessary to specify a higher power system voltage at the higher power ratings. In marine practice voltages below 1000 V are considered LV (low voltage). HV (high voltage) is any voltage above 1 KV. Typical marine HV system voltages are 3.3 KV and 6.6 KV. 11 KV Systems are emerging with the still increasing power demands. Low voltage side of the network the voltage levels are 440V, or 680V. By generating electrical power at 6.6 KV instead of 440 V the distribution and switching of power levels above about 6 MW becomes more practicable and manageable.
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