Lighting on ships. General Requirements

In all rooms, spaces and locations of the ship where lighting is ne cessary to ensure the safety of navigation, operating of machinery and equipment, as well as accommodating and evacuation of passengers and crew, stationary fixtures of main lighting are to be installed.

Lighting fixtures installed in rooms and spaces, where mechanical damage is possible to the glass hoods are to be provided with' protect ing gratings.

Lighting fixtures are to be installed in such a manner as to prevent heating of cables and adjacent materials up to a temperature exceeding the permissible level.

Permanently-installed lighting fixtures in holds are to take their po wer supply from a special switchboard. Apart from the fuses and swit ches this switchboard is to be provided with visual signals to monitor individual lighting circuits.

In rooms or places illuminated with luminiscent lamps where visible rotating parts of machinery are located, all measures to be taken to prevent stroboscope effect.

When using d-c, a label indicating the voltage level is to be fitted on switchboards feeding the discharge lamps.

Capacitors

The capacity of a capacitor is measured in farads. A capacitor has a capacity of 1 farad when a charge of 1 coulomb increases the potential, between its plates, by 1 volt.

The capacity depends on four things: a) the higher the voltage used to charge the capacitor the more energy it will store; b) the larger the sizes of plates and the greater their number the more energy will be stored; c) the closer are the positive and negative plates the greater is the charge; d) some insulators store greater charge than others.

Capacitor in A-C Line

When a capacitor is connected into a circuit through which alternat ing current is flowing, the plates of the capacitor are charged negatively or positively.

In order to show the action of a capacitor, in an a-c line, connect a capacitor in series with a lamp and plug into the a-c lighting. The lamp will glow provided its resistance does not prevent. Then connect another capacitor in parallel and the lamp will glow brighter. 

Connecting more capacitors and increasing the capacity we increase the glow. Thus, capacitors oppose the flow of current.