Contents:- #What is Grounding or Earthing? #Symbol #Earthing cable #History #How Earthing works? #Difference between Earth & Neutral #Importance of Earthing #Components of earthing system #Types of Earthing

1. EARTHING
What is Grounding or Earthing?
 The term Grounding or Earthing means connecting the electrical equipment to the general mass of the earth
such that there is always an immediate discharge of energy taking place without any danger of electric shock.
 In other words, to connect the metallic parts of electric machinery and devices to the earth plate or earth electrode
(which is buried in the moisture earth) through a thick conductor wire (which has very low resistance) for safety
purpose is known as Earthing or Grounding.
 Earthing can be said as the connection of the neutral point of a power supply system to the earth so as to avoid or
minimize danger during discharge of electrical energy.

2. SYMBOL
OR

3. EARTHING CABLE
Earthing cable mostly comes in two colors:-
Green Green-Yellow

4. HISTORY
 Long distance electromagnetic telegraph systems from 1820 onwards used two or more wires to carry the signal &
return currents.
 It was then discovered, probably by German Scientist Carl August Steinheil in 1836-1837 that ground could be
used as the return path to complete the circuit, making the wire unnecessary.

5. HOW EARTHING WORKS?
 In any electrical installation, if the metallic part of the electrical appliance such as the metallic frame, metal
covering of cables, etc. comes in direct contact with a live wire, the metal will begin to get charged since it is a
good conductor of electricity.
 A common reason behind the metallic part of the appliance coming in contact with the live wire is breakdown of
insulation.
 With the metallic part now charged, if a person comes in contact with it, he will get a severe shock.
 The moment at which the metallic part is earthed, the charge that had accumulated on it due to the failure of
insulation, would immediately be transferred to the earth. In this way, people can be saved from getting an
electrical shock.

6. DIFFERENCE BETWEEN EARTH & NEUTRAL
Earth(Ground) Neutral
• Earth or Ground in a mains(AC
power) electrical wiring system is a
conductor that provides low
impedance path to the earth to prevent
hazardous voltages from appearing on
equipment & brings back the fault
current.
• Ground is not neutral
• Color of earth wire is green or green-
yellow mixture
• Neutral is a circuit conductor that
normally carries current back to the
source, and is connected to
Earth(Ground) at the main electrical
panel.
• Neutral can be grounded
• Color of neutral wire is black

7. IMPORTANCE OF EARTHING
 To protect human lives as well as provide safety to electrical devices and appliances from leakage current.
 To keep voltage as constant in the healthy phase (If fault occurs on any one phase).
 To protect electric system and buildings form lighting.
How?

8. A lightning rod /lightning conductor/lightning arrestor is a metal rod or metallic object mounted on top of an elevated
Structure, such as a building, a ship , or even a tree, electrically bonded using a wire or electrical conductor to
interface with Ground or Earth through an electrode , engineered to protect the structure in the event of lightning
strike.
If lightning hits the structure, it will preferentially strike the rod and be conducted to ground through the wire,
instead of passing through the structure, where it could start fire or cause electrocution.
 To serve as a return conductor in electric traction system and communication.
 To avoid the risk of fire in electrical installation systems.
 To get earth’s healing energy.
How?
Human beings evolved in connection with the earth’s energy. We walked barefoot and we slept in contact with the
earth never realizing that its surface contained limitless, natural, healing energy. We live indoors much of the time
and when we go outside we wear rubber soled shoes which creates an insulation between the earth and us. Rubber is
not conductive, but our bodies are!
The earth is basically a six sextillion metric ton battery that is continually being replenished by solar radiation,
lightning and heat from its deep-down molten core. So, earthing is simply reconnecting to the earth’s healing energy.
Why not use it? It’s totally free!

9. COMPONENTS OF EARTHING SYSTEM

10. Earth: The proper connection between electrical installation systems via conductor to the buried plate in the earth is known
as Earth.
Earth Electrode: When a conductor (or conductive plate) buried in the earth for electrical earthing system. It is known
to be Earth Electrode. Earth electrodes are in different shapes like, conductive plate, conductive rod, metal water pipe
or any other conductor with low resistance.
Earthing Lead: The conductor wire or conductive strip connected between Earth electrode and Electrical installation
system and devices in called Earthing lead.
Earth Continuity Conductor: The conductor wire, which is connected among different electrical devices and appliances
like, distribution board, different plugs and appliances etc. in other words, the wire between earthing lead and
electrical device or appliance is called earth continuity conductor. It may be in the shape of metal pipe (fully or partial),
or cable metallic sheath or flexible wire.

11. TYPES OF EARTHING
 Pipe Earthing

12. Pipe earthing is best form of earthing and it is cheap also in this system of earthing a GI pipe of 38 mm diameter and
2meters length is embedded vertically in ground to work as earth electrode but the depth depend upon the soil
conditions, there is no hard and fast rule for this.
But the wire is embedded upto the wet soil.
The earth wire are fastened to the top section of the pipe with nut and bolts.
The pit area arround the GI pipe filled with salt and coal mixture for improving the soil conditions and efficiency of the
earthing system.
It can take heavy leakage current for the same electrode size in comparison to plate earthing.
The earth wire connection with GI pipes being above the ground level can be checked for carrying out continuity test
as and when desired, while in plate earthing it is difficult.
In summmer season to have an effective earthing three or four bucket of water is put through the funnel for better
continuity of earthing.

13.  Plate Earthing
In this type of earthing plate either of copper or of G.I. is buried into the ground at a depth of not less than 3 meter from
the ground level.

14. The earth plate is embedded in alternative layer of coke and salts for a minimum thickness of about 15cm.
The earth wire(copper wire for copper plate earthing and G.I. wire for G.I. plate earthing) is securely bolted to an earth
plate with the help of bolt nut and washer made of copper, in case of copper plate earthing and of G.I. in case of G.I.
plate earthing.

15.  Rod Earthing
It is the same method as pipe earthing. A copper rod of 12.5mm (1/2 inch) diameter or 16mm (0.6in) diameter of
galvanized steel or hollow section 25mm (1inch) of GI pipe of length above 2.5m (8.2 ft) are buried upright in the earth
manually or with the help of a pneumatic hammer. The length of embedded electrodes in the soil reduces earth resistance
to a desired value.