Letters used to designate the different services are
The color coding of conductors in power and light
shown in table 2-4.
cables is shown in table 2-3. Neutral polarity,(), where
it exists, is always identified by the white conductor.
Voltages below 100 volts are designated by the
actual voltage, for example, 24 for a 24-volt circuit. The
Cable Markings
number "1" is used to indicate voltages between 100 and
199; "2" for voltages between 200 and 299; "4" for
voltages between 400 and 499; and so on. For a three
Metal tags embossed with the cable designation are
wire (120/240), dc system or a three-wire, three-phase
used to identify all permanently installed shipboard
system, the number used indicates the higher voltage.
electrical cables. These tags, when properly applied,
make it easy to identify cables for maintenance and
The destination of cables beyond panels and
replacement purposes.
switchboards is not designated except that each circuit
alternately receives a letter, a number, a letter, and so on
The marking system for power and lighting cables
progressively, each time it is fused. The destination of
consists of three parts in sequence: source, voltage, and
service. Where practical, the destination of the cable is
power cables to power consuming equipment is not
shown as well. Each of the parts are separated by
Table 2-4.--Cable service designation letters
hyphens.
Table 2-3.--Color Code for Power and Lighting Cable
Conductor
2-12
