the switchboard. Then, it can be used exclusively for
of the casualty power system. This system provides the
casualty power purposes.
means for making temporary connections to vital
circuits and equipment. The casualty power distribution
system is limited to those facilities that are necessary to
RIGGING CASUALTY POWER
keep the ship afloat and permit it to get out of the danger
area. It also provides a limited amount of armament,
To eliminate the necessity of handling live cables,
such as weapons systems and their directors to protect
and to reduce the hazards to personnel and equipment,
the ship when in a damaged condition.
there are definite procedures that must be followed and
safety precautions that must be observed in rigging
Optimum continuity of service is ensured in ships
casualty power.
provided with ship's service, emergency, and casualty
power distribution systems. If one generating plant
Only qualified Electrician's Mates should do the
should fail, a remote switchboard can be connected by
actual connecting; however, the portable cables maybe
the bus tie to supply power from the generator or
laid out by other repair party personnel. The repair party
generators that have not failed
electrician must wear rubber gloves, rubber boots, and
stand on a rubber mat while making connections. Each
If a circuit or switchboard fails, the vital loads can
casualty power riser or bulkhead terminal must be tested
be transferred to an alternate feeder and source of ship's
with a voltage tester before a connection can be made to
service power by means of a transfer switch near the
that terminal. It is the duty of the repair party
load
Electrician's Mate to determine that all sources of power
If both the normal and alternate sources of the ship's
to the equipment concerned are de-energized before
service power fail because of a generator, switchboard,
rigging casualty power. The portable cable connections
or feeder casualty, the vital auxiliaries can be shifted to
for casualty power should always be made by first
an emergency feeder that receives power from the
connecting the load and then working back to the source
emergency switchboard.
of power.
If the ship's service and emergency circuits fail,
On large ships, casualty power runs involve more
temporary circuits can be rigged with the casualty power
than one repair party. All repair parties should rig
distribution system and used to supply power to vital
simultaneously, but the rule of "rig from load to source"
auxiliaries if any of the ship's service or emergency
should always be observed. Each repair party must
generators can be operated.
report its section rigged from riser or bulkhead terminal
number to riser or bulkhead terminal number to damage
The casualty power system includes suitable
control central (DCC).
lengths of portable cable stowed on racks throughout the
ship. Permanently installed casualty power bulkhead
In all instances of rigging and energizing any part
terminals form an important part of the casualty power
of the casualty power system, only the damage control
system. They are used for connecting the portable
assistant, with the authority of the chief engineer, has
cables on opposite sides of bulkheads, so that power
the authority to order the system energized.
may be transmitted through compartments without loss
In making casualty power connections at a load
of watertight integrity; also included are permanently
where there are no circuit breakers or transfer switches
installed riser terminals between decks. The vital
to interrupt the incoming feeder cable, the load must be
equipment selected to receive casualty power will have
disconnected or cut at the equipment. It is quite possible
a terminal box mounted on or near the equipment or
that the feeder cable may be damaged by the casualty
panel concerned and connected in parallel with the
that caused the loss of power. A damaged cable, if
normal feeder for the equipment.
energized, would probably trip the casualty power
Sources of supply for the casualty power system are
circuit breakers. If not disconnected, this incoming
provided at each ship's service and emergency generator
feeder cable may be re-energized and present a hazard
switchboard. A casualty power riser terminal is
to personnel handling the casualty power cables.
installed on the back of the switchboard or switchgear
To keep the phase sequence correct in ac systems,
group (fig. 3-45) and connected to the busses through a
exercise care in making all connections. The riser
225- or 250-ampere AQB circuit breaker. This circuit
terminals, bulkhead terminals, and portable cable ends
breaker is connected between the generator circuit
are marked to identify the A-, B-, and C-phases. You
breaker and the generator disconnect links. By opening
can make the identification visually by color cede. In
the disconnect links, you will isolate the generator from
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