1. A cable is most often two or more wires running side by side and bonded,
twisted, or braided together to form a single assembly, but can also refer to a
heavy strong rope.
2. MAIN CABLE COMPONENTS
• An electric cable is made up of a conductor, which channels the electricity flow, and
an insulation that contains this electricity flow in the conductor. Moreover, other
auxiliary elements can be included which ensure its longevity.
• The conductor is where the electric current is actually transmitted, with copper
being generally the most used material.
• The insulation is the layer of polymer, plastic or elastomer which surrounds the
conductor and insulates it from external contact.
3. COLOR CODE
•To enable wires to be easily and safely identified, all common wiring
safety codes mandate a colour scheme for the insulation on power
conductors. In a typical electrical code, some colour-coding is
mandatory, while some may be optional. Many local rules and
exceptions exist. Older installations vary in colour codes, and colours
may shift with insulation exposure to heat, light, and aging.
•Many electrical codes now recognize (or even require) the use of wire
covered with green insulation, additionally marked with a prominent
yellow stripe, for safety grounding (earthing) connections. This growing
international standard was adopted for its distinctive appearance, to
reduce the likelihood of dangerous confusion of safety grounding wires
with other electrical functions, especially by persons affected by red-
green colour blindness.
4. PROPERTIES
Electric Properties:
- dielectric strength
- insulation resistance
- insulation power factors
- charging current
- arc resistance
-tracking susceptibility
Mechanical Properties:
- toughness and flexibility
- tensile, elongation and crushing strengths
- resistance to abrasion or moisture
-Brittleness
Chemical Properties:
- moisture absorption
- resistance to oil, gas, acids and alkalis
-stability when exposed to sunlight, ozone, or flames
Thermal Properties:
- expansion and contraction
- softening and flow temperature
- compatibility with operating, ambient, or emergency overload and short circuit
conditions
5. CONDUCTOR
MATERIALS
Copper
•The principal electrical conductor due to its excellent conductivity and
reasonable cost.
Aluminum
•61% the conductivity and .3027 times the weight of copper. Used in power
cables, overhead (ACSR), and some building wire.
Copper weld
•A thin coating of copper fused to a steel core. Used in line wire, cable
messengers and stranded with copper for strength or extending flex life.
Alum weld
•A thin coating of aluminum fused to a steel core. Used in line wire and cable
messengers.
Tinsel
•Flat ribbons of bronze, silver, or copper alloy spiraled around a textile core of
cotton, nylon, etc. Used in telephone and electronics applications as conductors
in line cords, microphone cords, and retractile cords.
Thermocouple
•Special matched Alloy Conductors. Used in temperature measuring
applications
6. TYPES OF CABLES
Coaxial Cable: Coaxial cable is made up of a copper conductor
surrounded by a layer of flexible insulation. The center conductor can
also be made of tin plated aluminum cable allowing for the cable to be
manufactured inexpensively. Over this insulating material is a woven
copper braid or metallic foil that acts as the second wire in the circuit
and as a shield for the inner conductor. This second layer, or shield also
reduces the amount of outside electromagnetic interference. Covering
this shield is the cable jacket. Cable television uses coaxial cable.
7. TYPES OF CABLES
Shielded Twisted Pair : STP cable uses cancellation, shielding, and
twisted wires. The twisted wires and shielded twisted-pair cables allow
for more cancellation of electrical interference than the unshielded
twisted-pair cables. Each pair of wires is wrapped in metallic foil and
those four pairs of wires are wrapped in an overall metallic foil.
8. TYPES OF CABLES
Unshielded Twisted Pair : UTP is a four-pair wire medium used in a
variety of networks. Each of the eight copper wires in the UTP cable is
covered by insulating material. In addition, each pair of wires is twisted
around each other. This type of cable relies on the cancellation effect
produced by the twisted wire pairs to limit attenuation3 caused by
electromagnetic interference and radio frequency interference.
10. 600V SINGLE CONDUCTOR CABLE
It consists of an insulation ,magnetic shield
and rubber jacket. Many thin conductors are
kept together which acts like a single
conductor.
11. ARMORED CABLE
Steel wire armored cable, commonly
abbreviated as SWA, is a hard-
wearing power cable designed for the
supply of mains electricity.
13. CONTROL CABLE
Control Cable is a flexible instrumentation cable designed for
measuring, control or regulation in the field of process automation.It is
a highly flexible multicore cable, with (class 5) copper conductors and
a galvanised steel wire braid (GSWB) for mechanical protection. The
cable is typically manufactured with PVC insulation, bedding and a
transparent PVC sheath.The transparent sheath means signs of
deterioration, damage or corrosion can be detected with ease.
15. COPPER CABLE
Copper wire is used in power
generation, power transmission,power
distribution, telecommunications, electro
nics circuitry
16. LOW VOLT INDUSTRIAL CABLE
These cables are generally
used in low voltage
applications in industry. It is
used in industrial wiring.
17. POWER CABLE
These cables are used to transmit
electricity from power station to
consumers over long distances.
Overhead lines use this type of cables.
18. MEDIUM VOLTAGE POWER CABLE
These cables are used in
medium voltage applications
like supply cables in a
residential area.
20. SHIELDING POWER CABLE
A shielded cable is an electrical cable of one or more insulated
conductors enclosed by a common conductive layer.
The shield may be composed of braided strands of copper (or
other metal, such as aluminium), a non-braided spiral winding
of copper tape, or a layer of conducting polymer.
21. PORTABLE CABLE
Portable cable is a cable with
multiple conductors used for functions
requiring flexibility. The cord can be
employed for power in a range of
applications, such as operating motors in
small and large tools, equipment, power
extensions, home
appliances and machinery.
Portable cords may be used in commercial,
industrial and residential applications. They
work well on job sites where resistance
to oil, chemicals and abrasion is vital and
also perform well in extreme environments
- both the heat and the cold, outside or
inside.
22. TELEPHONE CABLE
As the name suggests it used in
telephones. It consists of a thin copper
conductor surrounded by
insulation.One telephone cable
contains three to four of these
conductors.