Marine fans are a new type of ventilation equipment manufactured from corrosion-resistant fibreglass reinforced plastic (FRP), classified as axial flow fans. Utilising a corrosion-resistant FRP outer casing, their operating principle employs negative pressure ventilation to achieve air circulation, ventilation, and cooling. 1. Starting the fan at full voltage or reduced voltage Marine fans can be started at either full voltage or reduced voltage. However, certain precautions apply. Specifically: - When starting at full voltage, the starting current should be 5-7 times the rated current. - When starting at reduced voltage, the starting torque is proportional to the square of the voltage. 2. Requirements for trial operation runs Are there requirements for the number of trial operation runs?