Ship normal lighting system, also known as the main lighting system, is distributed in various living and working places inside and outside the ship, providing sufficient illumination for each cabin and workplace.

The characteristics of the system are as follows: the lighting bus on the main distribution board directly supplies power to each lighting distribution box, and then the lighting distribution box supplies power to the lighting lamps in the adjacent cabin or area;

The lighting voltage is generally 110 V or 220 V AC or DC;

Different cabins and places have different illumination requirements; all lighting lamps are equipped with control switches.

Normal lighting is the main lighting of the whole ship. It is powered by the main generator of the ship. It should be illuminated wherever the ship lives and works.

Normal lighting includes:

(1) Cabin main lighting, such as most of the ceiling lights;

(2) Local or auxiliary lighting, such as bed lamp, wall lamp, toilet lamp, etc;

(3) Loading and unloading strong lighting;

(4) Lighting of more than half of indoor and outdoor walkways;

(5) All cabins must be provided with sockets, etc.

Non important equipment with a rating of 0.25 kW or less, such as electric fans, refrigerators and cabin electric heaters, can also be included in the normal lighting system.