Normally underground power cable contain one or more conductor which is covered with insulation. Most of underground cables are used for high electric power distribution purposes under urban areas. There are different types of cables mostly constructed to handle a certain range of voltages. Each of the cable type has its own pros & cons. The underground cables have several merits over the overhead lines; they have smaller voltage drops, low chances of developing faults and have low maintenance costs. We Bore It, a leading directional & boring service provider always prefer underground wiring whenever they get request for installing wires in illinois or other regions.

1. Cables and their Implications in Underground Wiring
Underground wiring technique has been around for many years
now and is widely implemented by various drilling and boring
companies. It is a technique that involves replacement of the
overhead cables with underground cables. Underground wiring is
mainly used for applications where overhead setup is dangerous or
not feasible. The two important benefits of underground wiring
system are - protection of power lines from external hazards; all of
the interconnections and cable mess goes underground – not
visible to the human eyes. This type of wiring system is promoted
for use in densely populated (urban) areas and factories.

2. Cables and their Implications in Underground Wiring
Underground wiring or undergrounding technique uses different
types of underground cables varying according to their
applications. These cables, just like overhead cables, act as
conductors for transmission of electrical power. However, the
interference with amenities is comparatively less, thus, ensuring
better safety of the public. Underground cables are classified into
different categories on the basis of two criteria: type of insulating
material used for construction and voltage capacity.
Cable Classification on the basis of voltage capacity
This type of categorization is popularly prefered by the
underground wiring service providers. Below mentioned are all
the categories in ascending order of the voltage capacity.
• Low Tension (L.T) cables with maximum 1000V capacity
• High Tension (H.T) cables with maximum 11000V capacity.
• Super Tension (S.T) cables ranging from 22000V to 33000V
capacity
• Extra-high tension cables ranging from 33000V to 66000V

3. Cables and their Implications in Underground Wiring
capacity
• Extra Super Voltage cables with minimum capacity of
132000V
Cable Classification on the basis of insulation material
Normally, underground cables are used to deliver three-phase
power and to serve the purpose, three core cable is usually
prefered. There are three main types in this category which are
specified below.
• Belted cables (maximum voltage 11KVA)
The cores in this cable are insulated with the help of an
impregnated paper. To utilize the available space in a better way,
the shape of these cores is designed non-circular. In case of a three
core cable, the cores are grouped together and belted with a paper
belt. A fibrous material, like jute, is inserted in the gaps formed
between the conductors and paper insulation. To protect the paper
belt from moisture and provide mechanical strength, a lead sheath
is used. At last, the sheath is layered with armor materials and an

4. Cables and their Implications in Underground Wiring
outer cover.
• Screened cables (maximum voltage 66KVA)
This type of cable is further classified into subtypes : H type and
S.L type
H Type
In a three core H type screened cable, each of the core is
insulated with an impregnated paper and then covered with a
pierced or perforated aluminium foil (or other metallic
screen). The arrangement of these screens is such that they
can make contact with each other.
SL Type
The construction of SL type is similar to the H type except
each insulated core is covered with its separate lead sheath.
However, it does not have an overall lead sheath.
• Pressure cables (maximum voltage more than 66 KVA)
These type of cables have a different construction where the
gap is eliminated by increasing the pressure of compound;
hence the name pressure cables. The two major types used

5. Cables and their Implications in Underground Wiring
are oil-filled and gas-pressure cables.
There are various underground wiring solution providers in USA
like hoerr, thomasnet, we bore it, etc who give reliable
underground wiring services. These companies have years of
experience and deliver timely undergrounding services. Opting for
the most affordable and dependable excavating company is the
need of the hour to avoid accidents. Rely only on experienced
companies for best results.