Difference Between Grounding and Earthing

One of the major difference between the grounding and the earthing is that in grounding, the current carrying part is connected to the ground whereas in earthing the non-current carrying parts is connected to ground. 

Definition of Grounding :-

In grounding, the current carrying parts are directly connected to the ground. The grounding provides the return path for the leakage current and hence protect the power system equipment from damage. 

When the fault occurs in the equipment, the current in all the three phases of the equipment become unbalance.The grounding discharges the fault current to the ground and hence makes the system balance.

The grounding has several advantages like it eliminates the surge voltage and also discharge the over voltage to the ground. The grounding provides the great safety to the equipment and improves the service reliability.

Definition of Earthing :-

The ‘earthing’ means the connection of non-current carrying part of the equipment to the earth. When the fault occurs in the system, then the potential of the non-current part of the equipment raises, and when any human or stray animal touch the body of the equipment, then they may get shocked. 

The earthing discharges the leakage current to the earth and hence avoid the personnel from the electric shock. It also protects the equipment from lighting strokes provides the discharge path for the surge arrester, gap and other devices.

The earthing is achieved by connecting the parts of the installation to the earth by using the earth conductor or earth electrode in intimate contact with the soil placed with some distance below the ground level.

Key Differences Between Grounding and Earthing :-

1. The earthing is defined as the connection of the non-current carrying part like the body of the equipment or enclosure to earth. In grounding the current carrying part like neutral of the transformer is directly connected to the ground.
2. For grounding, the black colour wire is used, and for earthing the green colour, the wire is used.
3. The grounding balanced the unbalanced load whereas the earthing protect the equipment and human from an electrical shock.
4. The grounding wire is placed between the neutral of the equipment and the earth whereas in earthing the earth electrode is placed between the equipment body and the earth pit which is placed under the ground.
5.  In grounding the equipment is not physically connected to the ground, and the current is not zero on the ground, whereas in earthing the system is physically connected to the ground and it is at zero potential.
6. The grounding gives the path to an unwanted current and hence protects the electrical equipment from damage, whereas the earthing decrease the high potential of electrical equipment which is caused by a fault and thus protects the human body from the electrical shock.
7. The grounding is classified into three types. They are the solid grounding, resistance grounding and reactance grounding. Earthing can be done in five ways.The different methods of earthing are the pipe earthing, plate earthing, rod earthing, earthing through tap and strip earthing.

Which is more dangerous to the human body: AC or DC current and voltage?

The effects of both on the human body differ, but one is more hazardous than the other.


No matter what, if either AC or DC comes in contact with the human body, it can be hazardous. The actual effect varies, though, as it depends upon several different factors, including the amount of current administered, duration of which it was in contact with the body, pathway of the current, voltage applied, and impedance of the body itself. 

All of that being said, if it comes down to one or the other, AC can generally be viewed as the more dangerous of the two currents — here’s why:

1) To start off, in order for both currents to have the same effect on the human body, the magnitude of DC flow of constant strength needs to be two to four times great than AC; that is, more DC current is needed to induce the same amount of physical damage as AC current. This is because the effect of the currents on the body is a direct result of the excitatory actions of its magnitude — specifically, the actual making and breaking of the current itself. Such excitatory actions include nerve / muscle stimulation, induction of cardiac atrial or ventricular fibrillation, and more. 

For DC to produce the same effect as AC on the human body, its flow of constant strength must be two to four times that being administered by the AC.

2) When death by electric shock occurs, it’s typically due to ventricular fibrillation, and the likelihood of a human suffering this sort of life-ending injury is much higher when coming in contact with an AC than a DC due to the fact that the human body’s threshold of DC-caused ventricular fibrillation is several times higher than for AC. 

3) Generally speaking, the human body’s impedance is higher for DC, and it only decreases when the frequency increase. As such, the severity of electric shock is less when in contact with DC than it is with AC. 

4) It’s easier to let go / remove contact with “live” parts in the case of DC than AC. This runs counter to the popular belief that because the alternating cycles of an AC current pass through zero, the individual is afforded enough time to pull their limb / body away from the part itself, whereas with the constant flow of the DC current, there is no frequency oscillations that afford the brief moment for the person to pull their body away. The basis for this argument can be sourced in the “let-go” experiment, which was reported in the same aforementioned IEC publication 60479. In it, the lowest level of current that could safely pass through a human body was administered through an electrode held in a test person’s hand; it was enough current to make the person unable to open his hand and drop the electrode. 

Without getting into all of the details of the actual experiment, the conclusion was that the test subjects found it easier to release the electrode when DC was administered rather than AC. 

Now, while it can be surmised that AC is more dangerous than DC, the safest solution is to avoid contact with any and all high-voltage electrical conductors, no matter the type of electrical current. As mentioned at the beginning of the article, any contact with an electrical current can be hazardous.