What is a neutral wire and what is it used for? How is a neutral wire different from ground and hot wire?

A neutral wire is used to complete the flow of electricity, it acts as a return path for the hot wire current. A hot wire is a wire that will provide the electric source and it will be alternating current. The neutral wire will be connected to the earth ground, the color of the neutral wire could be grey or white. During normal operations, the neutral wire will carry current. We can see neutral in most of the electrical equipment, mostly in non-linear loads.

What is the purpose of neutral in power transmission?

The power from the substation reaches to our home by through a step-down transformer, the power from the substation could be 11KV and this power is reduced by using the step-down transformer so that we can use it as 230/415V,  the output of this step-down transformer would have a neutral. The neutral is the point in which the three windings of the transformer meets up, we can consider the neutral as the star-point of the transformer. A neutral act as a return path so that the electric circuit can be completed and also the electricity travels from a high potential to low potential and so the neutral could be used to complete the electric circuit. In the transformer, the neutral point will be grounded to prevent the back current flow and this flow could happen in an unbalanced system.

Can we get an electric shock from a neutral wire?

Yes there is a chance to get shocked from a neutral wire, mostly a neutral wire is considered to have a zero potential but in the case of an unbalanced system this could vary and that’s why a neutral wire is connected to the ground. If the neutral path to the ground is not good then it could be harmful too.

Do we need to connect the neutral wire to the ground?

If we use a protective system like RCCB or anything like that, it would only trip only if the current enters the device is not the same as the current that reaches the device through the neutral so if the neutral is grounded then the current will travel through it and the protective device won’t trip and there won’t be any protection for earth leakage. There is also a chance that the current consumption will be high when the neutral is grounded, so we would need to pay extra for the electric power that we didn’t use.

What is the difference between a neutral and ground?

A ground wire is used in AC mains, so that it could provide a low impedance path and by that it could prevent high voltages and could protect the equipment. Whereas a neutral is a conductor that carries the current from the hot wire and it would be sent to the source. A neutral wire can be grounded, the color of the ground wire could be green and the color of neutral wire could be white or grey. Grounding is done in parts or conductors that carry current and the ground wire won’t carry any electrical current during the normal operating conditions. So in case if there is an electrical fault then only the ground wire will allow the flow of electrical current and the resistance of the ground wire will be very less so that during any fault conditions the electricity will choose to travel through the ground wire. So grounding is done to most of the electrical equipment so that if the hot wire touches the metal part of the equipment it won’t hurt any personnel.

What is the difference between a neutral wire and a hot wire?

Electric current will only travel in a complete circuit and it will flow from high potential to low potential. The electric current will return to its source and that’s how it completes a circuit. In the above image, we can see a live wire or hot wire is used to carry the current from the current supply and it will reach the equipment or the load through the neutral wire. This current in the equipment needs to flow to the current supply or the load and this is done by using a neutral wire.

News Reporter
post-graduate in Electronics & communication