CHAPTER 4
SHIPBOARD LIGHTING
LIGHTING DISTRIBUTION
As an Electrician's Mate, you are responsible for
SYSTEMS
maintaining the lighting distribution system aboard
naval ships. This system comprises the ship's service
The lighting distribution system in naval ships is
general lighting, and navigation and signal lights,
designed for satisfactory illumination, optimum
including searchlights.
operational economy, maximum continuity of service,
and the minimum vulnerability to mechanical and battle
The lighting system must maintain the continuity of
damage. Most ships have the following sources of
power to selected vital lighting circuits. This is done by
lighting available:
means of separate power sources and switching
equipment that selects, in an orderly fashion, a power
A normal (ships' service) supply from the ship's
source suitable for proper system operation.
service bus
An emergency (or alternate) source of power to
LEARNING OBJECTIVES
supply a designated number of fixtures
Relay-operated battery-powered hand lanterns
Upon completion of this chapter you will be able to:
1. Identify the purpose of both the normal and
SHIPS' SERVICE LIGHTING
emergency lighting distribution system.
DISTRIBUTION SYSTEM
2. Recognize the operation of the automatic bus
The ships' service lighting distribution system is
transfer (ABT) switch.
designed to meet the illumination needs of any activity
3. Identify the classification of lamps according to
throughout the ship. It is set up in such a manner as to
bulb shape, finish, and base.
provide a balanced load on each of the three phases
while providing power to both the ship service lighting
4. Identify the operating characteristics of
system and the 120-volt auxiliaries. These auxiliaries
incandescent and fluorescent lamps and
include hotel services such as coffee makers, drinking
fixtures.
fountains, toasters, and small tools.
5. Identify the various navigation and signal lights
It consists of feeders from the ship's service or
used aboard ship.
emergent y power switchboards, switchgear groups, or
6. Identify the maintenance requirements for the
load centers to distribution panels or feeder distribution
various lighting fixtures in use aboard ships
points, which supply power to local lighting circuits.
today.
The lighting supply circuits are 450-volt, three-phase,
At times you will be directed to install new lighting
60-hertz, three- wire circuits supplied from the power
circuits or equipment and may find yourself without
distribution system to 450/120-volt transformer banks.
installation plans or drawings. Other times you will be
correcting deficiencies found while conducting PMS
EMERGENCY LIGHTING
checks, routine tests, or inspections. For these and
DISTRIBUTION SYSTEM
various other reasons you should be very familiar with
The emergency or alternate lighting distribution
the lighting system aboard your ship. Always refer to
system is designed to provide a suitable distribution
the applicable blueprints, drawings, and Ship
system that, upon failure of the ships' service lighting
Information Book, volume 3, "Power and Lighting
system, will assure continuity of lighting in vital spaces
Systems," before attempting repairs on the system.
Additional information is found in Naval Ships'
and inboard watch stations. Continuous illumination is
Technical Manual (NSTM), chapters 300, 320, 330, 422,
essential in these areas because of functional
requirements, and when personnel are required to
and 583, and "Lighting on Naval Ships," NAVSEA
remain on duty.
0964-000-2000.
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