SHRI GOVINDRAM

SEKSARIA INSTITUTE OF
SCIENCE AND
TECHNOLOGY
ELECTRICAL WORKSHOP
POWER POINT PRESENTATION ON:

ELECTRICAL WIRINGS-DOMESTIC &

INDUSTRIAL
SUBMITTED TO: SUBMITTED BY:
ASHUTOSH SIR
AAKASH LILHORE- 0801EE141001
AAYUSHI KHADIKAR- 0801EE141002
AISHWARYA KAUSHAL- 0801EE141006
AYUSHI JAIN- 0801EE141020

TABLE OF CONTENTS

Electrical wiring
Types of wiring according to use
Factors affecting the choice of wiring
Domestic Wiring- 1.Types of wirings
2.Conditions for domestic
installations
Colour coding
Industrial Wiring
Forms of Wires
Conclusion

ELECTRICAL WIRING
Electrical wiring is generally refers to
insulated conductor used to carry
current and associated device. This
presentation describes general
aspects of electrical wiring as used to
provide power in buildings and
structures, commonly referred to as
building wiring. Building wiringis
the electrical wiring and associated
devices such as switches, meters and

TYPES OF
WIRING
ACCORDING TO
USE:
DOMESTIC WIRING

FACTORS AFFECTING THE CHOICE OF

WIRING:
Type of wiring selected should conform
to
standard specifications, so that it is
durable i.e.
without being affected by the
weather conditions,
fumes , etc.
2. SAFETY:
The wiring must provide safety against
leakage ,
shock and fire hazards for the
operating
personnel.
3. APPEARANCE: Electrical wiring should give an aesthetic
appeal
to the interiors.
4. COST:
It should not be prohibitively expensive.
5. ACCESSIBILTY:
The switches and plug points
provided should be
easily accessible. There must
be provision for
further extension of the wiring
system, if
necessary.
6. MAINTENANCE COST: The maintenance cost should be a
minimum.
7. MECHANICAL SAFETY: The wiring must be protected
1. DURABILITY:

DOMESTIC

DOMESTIC WIRING
TYPES OF WIRINGS :

1. Cleat wiring
2. CTS wiring or TRS wiring
or
batten wiring
3. Metal sheathed wiring or
lead sheathed wiring
4. Casing and capping
5. Conduit wiring

1. Cleat wiring:
In this type of wiring, insulated conductors (usually VIR, Vulcanized Indian
Rubber) are supported on porcelain or wooden cleats. The cleats have two
halves one base and the other cap. The cables are placed in the grooves
provided in the base and then the cap is placed. Both are fixed securely on
the walls by 40mm long screws. The cleats are easy to erect and are fixed 4.5
15 cms apart. This wiring is suitable for temporary installations where cost
is the main criteria but not the appearance.

Advantages:
Easy installation
Materials can be retrieved for reuse
Flexibility provided for inspection, modifications and expansion.
Relatively economical
Skilled manpower not required.

Disadvantages:

Appearance is not good

Open system of wiring requiring regular cleaning.
Higher risk of mechanical injury.

2. CTS ( Cable Tyre Sheathed) / TRS

( Tough Rubber Sheathed ) / Batten
wiring:
In this wiring system, wires sheathed in tough rubber are used which
are quite flexible. They are clipped on wooden battens with brass
clips (link or joint) and fixed on to the walls or ceilings by flat head
screws. These cables are moisture and chemical proof. They are
suitable for damp climate but not suitable for outdoor use in sunlight.
Advantages:
TRS
is suitable
for lighting in low voltage installations.
Easywiring
installation
and is durable
Lower risk of short circuit.
Cheaper than casing and capping system of wiring
Gives a good appearance if properly erected.

Disadvantages:
Danger of mechanical injury.
Danger of fire hazard.
Should not be exposed to direct sunlight.
Skilled workmen are required.

3. Metal Sheathed or Lead

Sheathed wiring :
The wiring is similar to that of CTS but the conductors (two or three)
are individually insulated and covered with a common outer leadaluminium alloy sheath. The sheath protects the cable against
dampness, atmospheric extremities and mechanical damages. The
sheath is earthed at every junction to provide a path to ground for
the leakage current. They are fixed by means of metal clips on
wooden battens. The wiring system is very expensive. It is suitable
for low voltage installations.

Precautions to be taken during installation:

The clips used to fix the cables on battens should not react with the
sheath.
Lead sheath should be properly earthed to prevent shocks due to
leakage currents.
Cables should not be run in damp places and in areas where

Advantages:
Easy installation and is aesthetic in appearance
Highly durable
Suitable in adverse climatic conditions provided the joints
are not exposed.

Disadvantages:
Requires skilled labor
Very expensive
Unsuitable for chemical industries

4. Casing and Capping:

It consists of insulated conductors laid inside rectangular, teakwood
or PVC boxes having grooves inside it. A rectangular strip of wood
called capping having same width as that of casing is fixed over it.
Both the casing and the capping are screwed together at every 15
cms. Casing is attached to the wall. Two or more wires of same
polarity are drawn through different grooves. The system is suitable
for indoor and domestic installations.

Advantages:
Cheaper than lead sheathed and conduit wiring.
Provides good isolation as the conductors are placed apart reducing
the risk of short
circuit.
Easily accessible for inspection and repairs.
Since the wires are not exposed to atmosphere, insulation is less
affected by dust, dirt and climatic variations.

Disadvantages:
Highly inflammable.
Usage of unseasoned wood gets damaged by termites.

5. Conduit wiring:
In this system PVC (polyvinyl chloride) or VIR cables are run through
metallic or PVC pipes providing good protection against mechanical
injury and fire due to short circuit. They are either embedded inside
the walls or supported over the walls, and are known as concealed
wiring or surface conduit wiring (open conduit) respectively. The
conduits are buried inside the walls on wooden gutties and the wires
are drawn through them with fish (steel) wires. The system is best
suited for public buildings, industries and workshops.
Advantages:
No risk of fire and good protection against mechanical injury.
The lead and return wires can be carried in the same tube.
Earthing and continuity is assured.
Waterproof and trouble shooting is easy.
Shock- proof with proper earthing and bonding
Durable and maintenance free
Aesthetic in appearance
Disadvantages:
Very expensive system of wiring.

CONDITION FOR DOMESTIC

INSTALLATION

Height of switch board must be 1.3m to 1.75m

from floor
level.
Height of distribution board must be 1.5m to
1.75m from floor level.
The bottom of ceiling fan should have minimum
clearance of 2.75m.
All lamp should be fitted with a minimum
clearance of 2.75m above floor level.
For load above 4KW,3 phase supply must
arrange load should be equally shared.
In any building light wiring and power wiring
should be kept separate.
Power per circuit may take it as 800W or 1000W.

COLOUR CODING

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 typicalelectrical
code, some colour-coding is mandatory,

INDUSTRIAL
WIRING

INDUSTRIAL WIRING:
Every type of machine has unique requirements when it comes to
operator safety. From an electrical standpoint, industrial machine
equipment and tools - from drill presses to multi-motored automatic
machines - can present special fire and shock hazards.
You must identify conductors at each termination so they match the
identification markings on the diagrams attached to the machine.

Equipment-grounding conductors -- You

must use the colour green, with or without one or more yellow
stripes, to identify the equipment-grounding conductor (where
insulated or covered). International and European standards require
the use of a bicolour green-and-yellow for this purpose . You can use
conductors of other colours, provided the insulation or cover is
appropriately identified at all access points.
For grounded control circuits, you may use a green (with or without
one or more yellow stripes) or a bare conductor to connect the
transformer terminal to a grounding terminal on the control panel.

Other colours for the purpose of

identification as follows:
Black represents ungrounded line, load and control conductors at
line voltage.
Red represents ungrounded AC control conductors, at less than
line voltage.
Blue represents ungrounded DC control conductors.
Yellow represents ungrounded control circuit conductors that may
remain energized when the main disconnecting means is in the
OFF position. These conductors must be yellow throughout the
entire circuit, including wiring in the control panel and the external
field wiring. International and European Standards require you to
use orange for this purpose.
White or natural gray represents a grounded circuit conductor.
White with blue stripe represents a grounded DC current-carrying
circuit conductor. International and European standards require you
to use light blue for the neutral conductor .
White with yellow stripe represents grounded AC current-carrying
control circuit conductors that remain energized when the
disconnecting means is in the OFF position. For additional circuits
powered from different sources that remain energized when the

SPLICES
You are required to run conductors and cables from terminal to terminal
without splices. However, an exception allows you to install a splice in leads
attached to electrical equipment, such as motors and solenoids.

PANEL WIRING

This section requires you to support conductors in panels to keep them in

place. You're permitted to use wiring channels if they're made of a flameretardant insulating material. If you're working with back-connected control
panels, you must provide access doors or swing out panels that swing about
a vertical axis. Multiple-device control panels must have terminal blocks or
attachment plugs and receptacles to terminate and connect all outgoing
control conductors.

MACHINE WIRING
You must totally enclose conductors and their connection external to the
control panel enclosure in suitable raceways or enclosures. Unless used for
flexible connections involving small or infrequent movements, or connections
to normally stationary motors, limit switches and other externally mounted
devices, fittings used with raceways or multiconductor cables must be liquid
tight.

Wire connectors and connections

You are required to use pressure connectors to connect conductors to
devices with lug-type terminals that are not equipped with saddle
straps or equivalent means of retaining conductor strands. Under
certain conditions of use, the standard allows you to use solder
connections and wire-wrapped connections.

Raceway fill
The combined cross-sectional area of all conductors and cables is not
permitted to exceed 50% of the interior cross-sectional area of the
raceway. The fill provisions are based on the actual dimensions of the
conductors or cables used.

Junction and pull boxes

When constructing junction boxes and pull boxes, you must be
careful to exclude materials such as dust, flyings, oil and coolant.
After you complete all wiring operations, you must seal all unused
knockouts or openings.

FORMS OF WIRES

Solid wire
Solid wire, also called solid-core or single-strand wire, consists of one
piece of metal wire. Solid wire is useful for wiring breadboards. Solid
wire is cheaper to manufacture than stranded wire and is used where
there is little need for flexibility in the wire. Solid wire also provides
mechanical ruggedness; and, because it has relatively less surface
area which is exposed to attack by corrosives, protection against the
environment friendly.
Stranded wire
StrandedcopperwireStranded wire is composed of a number of small gauge wire bundled
or wrapped together to form a larger conductor. Stranded wire is
more flexible than solid wire of the same total cross-sectional area.
Stranded wire tends to be a better conductor than solid wire because
the individual wires collectively comprise a greater surface area.
Stranded wire is used when higher resistance tometal fatigueis
required.

Braided wire
A braided wire is composed of a number of small strands of wire
braided together. Similar to stranded wires, braided wires are better
conductors than solid wires. Braided wires do not break easily when
flexed. Braided wires are often suitable as an electromagnetic shield
in noise-reduction cables.
Number of strands
The more individual wire strands in a wire bundle, the more flexible,
kink-resistant, break-resistant, and stronger the wire is. But more
strands increase cost.
The lowest number of strands usually seen is 7: one in the middle, 6
surrounding it. The next level up is 19, which is another layer of 12
strands on top of the 7. After that the number varies, but 37 and 49
are common, then in the 70 to 100 range (the number is no longer
exact). Even larger numbers than that are typically found only in very
large cables.
For application where the wire moves, 19 is the lowest that should be
used (7 should only be used in applications where the wire is placed
and then does not move), and 49 is much better. For applications with
constant repeated movement, such as assembly robots
andheadphonewires, 70 to 100 is mandatory.

CONCLUSION
Modern electrical machine tool equipment
may vary from that of a single-motor
machine (such as a drill press that performs
simple, repetitive operations) to very large,
multimotored automatic machines, which
contain highly complex electrical control
systems. Typically, these machines are
especially designed, factory-wired, tested
by the builder and then erected in the plant.
You must install, support, and protect

THANK YOU