Firstly, the certification standards are different.
Land-based generator sets only need to meet the conventional mechanical and electrical industry standards, without mandatory ship inspection requirements. While regular marine generator sets must pass the CCS (China Classification Society) certification, with all components having ship inspection certificates, and all performance and safety indicators passing strict tests. Generator sets without ship inspection certificates cannot legally operate on ships.
Secondly, the cooling systems are completely different.
Most land-based generator sets use water tank fans for air-cooling, relying on the machine room air for cooling. The ship's cabin space is narrow and the ventilation conditions are poor. Marine generator sets mainly use sea-water heat exchangers, using seawater to remove heat, with internal freshwater circulation to isolate seawater corrosion, and suitable for the installation environment of a sealed ship cabin.
Thirdly, the environmental protection grades differ significantly.
The air in the sea contains a large amount of salt fog, which is very likely to cause metal rusting and circuit board short circuits. Marine generator sets use marine anti-corrosion coatings for the entire machine, choose stainless steel for fasteners, seal the electrical box to prevent moisture, and conduct three-proof encapsulation treatment for the windings, allowing them to operate stably in high humidity and salt fog environments for a long time. At the same time, the generator sets must pass the tilt and sway test. When the ship experiences a certain angle of lateral or longitudinal inclination, the lubrication and fuel supply systems must not exhibit abnormality. Ordinary land-based generator sets are prone to oil supply interruption and shutdown failures when the ship experiences swaying.
Fourth, the safety configurations have been specially upgraded.
Marine generator sets are equipped with double-layer high-pressure oil pipes, fuel leakage alarms, and complete reverse power protection functions. The ship cabin is a sealed and dangerous space, and the control standards for fuel leakage and electrical sparks are extremely high. In addition, most ships require multiple generator sets to be connected for power supply, and marine control screens come with mature parallel operation functions to meet the requirements for coordinated operation of the ship's power station. These are functions that ordinary land-based generator sets rarely have.
In summary, land-based generator sets are designed for land-based emergency backup and occasional short-term operation; marine generator sets are often the main power supply on ships, requiring long-term continuous full-load operation, and have higher reliability requirements. Never entertain the idea of taking a chance and installing the land-based equipment on the ship. Once there is a sudden failure at sea,the repair and rescue are difficult, directly threatening the safety of the entire ship.