The International Marine Contractors Association (IMCA) has published guidance on ‘Offshore vessel high voltage safety’ (IMCA SEL 031/IMCA M 217).

“As the demand for electrical power increases on vessels, especially on large offshore construction vessels with diesel electric propulsion installations, the supply current becomes too high for efficient and practical use of the usual shipboard 3-phase voltage supply of 440 Volts (V) AC,” explains IMCA’s Technical Director, Jane Bugler. “To reduce the level of running currents and fault current levels, it is necessary to specify a higher system voltage for the higher power-rated equipment.

“In marine practice, voltages below 1kV AC are considered LV (low voltage); HV (high voltage) is any voltage above 1kV. Typical marine HV system voltages are 3.3kV, 6.6kV and 11kV.”

Tags: International Marine Contractors Association (IMCA)