Because attenuation (power loss) in a line
(SHIPALTs). Before work is begun on a new cable
increases with its length, keep cables as short as
installation, cableway plans should be available. If
practicable. With the use of short lengths of cable,
repairs to a damaged section of installed cable
are to be made, information on the original
high-temperature locations, sharp bends, and strain on
installation can be obtained from the plans
the cable can be avoided.
of the ship's electrical system. These plans
Keep the number of connectors to a minimum to
are normally on file in the engineering department
reduce line losses and maintenance problems.
office (legroom) aboard ship. If a ship alteration
is to be accomplished, applicable plans not
Flexible cables are flexible only in the sense that
already on board can be obtained from
they will assume a relatively long bend radius. They are
the naval shipyard listed on the authorization
not intended to be stretched, compressed, or twisted;
for the SHIPALT at the planning yard for the
they are to be installed with this in mind. The flexibility
ship.
of cables can be expressed by their minimum bend
radius.
The measurement point for minimum radius of
Installing the Cables
bend should be that surface of the cable that is on
the innermost portion of the cable bend. Dimensions
Before installing new cable, you should survey
listed in the C a b l e C o m p a r i s o n H a n d b o o k
the area to see if there are spare cables in existing
(MIL-HDBK-299(SH)) are approximately 8 times
wireways and spare stuffing tubes that can be
the overall diameter of the cable or cord. During
used in the new installation. The following
the installation process, the minimum radius
considerations should be made when planning the cable
should be about 12 times the cable diameter for
run:
conduit bends, sheaves, and other curved surfaces
around which the cable or cord may be pulled under
Locate the cable so damage from battle will
tension.
be minimized, to include running cables along
Fabricated straps are used for holding the cables.
different well-separated paths to reduce the
They are snug, but not too tight. Back straps (used
probability of battle damage to several cables
to keep the cable away from a surface) are used for
simultaneously.
cable runs along masts or in compartments that are
Locate the cable run so physical and electrical
subject to sweating. In more recent installations,
interference with other equipment and cables will be
semicontour straps and cable bands are used for certain
avoided
applications.
Locate the cable so maximum dissipation of
The exact methods that you should use to
internally generated heat will occur.
install cables are included in the Electronics Installation
and Maintenance Book, NAVSEA 0967-000-0110.
Do not run cables on the exterior of
The
Cable Comparison Guide, N A V S E A
the deckhouse or similar structures above the
0981-052-8090, contains information about all types of
main deck, except where necessary because of the
electrical shipboard cable that was installed before
location of the equipment served, structural
1986.
interferences, or to avoid hazardous conditions or
locations.
For elementary and isometric blueprints of ship's
electrical cable wiring diagrams, their care and stowage,
Where practicable, route vital cables along
and the correction of blueprints after modification of
the inboard side of beams or other structural
their circuits, refer to Blueprint Reading and Sketching,
members. This location will give maximum protection
NAVEDTRA 12014.
against damage by flying splinters or machine-gun
strafing.
Cable Ends
When running cables, avoid
possible
high-temperature locations, if possible.
When connecting a newly installed cable to a unit
Run pulse cables separately, when possible, to
of electrical equipment, the first thing you should
determine is the proper length of the cable. Then, you
reduce coupling and interference.
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