When the supply is normal AC, nothing happens in the case of industrial applications as they use a three-phase supply. When the phases are all loaded equally, no current flows through the neutral conductor.
However, in domestic applications, the ground wire becomes hot and it carries the majority of current as it has the least resistance. As a result, when a person comes in contact with a defective device, he/she will be exposed to an electric shock.
What Happens if You Connect Neutral to Ground
In most circuits or electrical outlets, you will find three wires: hot, ground, and neutral. The hot wire is live and therefore, the most dangerous. You will most certainly get a shock if you touch it bare.
You can identify the wires by their colors. The live wires are usually black but can be red, yellow, or blue as well. The ground wire is generally green and the neutral wire is white.
If you connect the ground wire to the neutral, the ground wire will become hot. As a result, there will be a high possibility of electrical shock.
To operate an electrical appliance, you will need both hot and neutral wires. The hot wires carry the current to the appliance and the neutral wire brings it back to the electrical panel. That way, the circuit is completed.
The grounding wire, however, does not carry any current under normal circumstances. Its function is to redirect the surge of electrical current that occurs due to malfunction of devices or metal cases. Normally, it maintains the device at a voltage level of the ground so that you and the device remain at the same potential.
Once you connect the neutral to the ground, you could shock yourself or others upon touching the metal case. This is because the metal case is connected to the ground. So, if the neutral or live wire is connected to the ground, the ground will become a live wire and create a dangerous situation.
However, under normal circumstances, nothing should happen. There might be a slight voltage difference which will cause the ground fault circuit interrupter (GFCI) to trip. The GFCI does that by comparing the current in the hot wire to the current in the neutral wire.
Regardless, you should not connect the ground to the neutral or vice versa. For a three-phase system, the good practice is to make sure that the load on all phases is the same. In short, the ground wire or earth wire is only supposed to carry current in times of emergency.
Can I Connect Neutral to Ground
As explained above, connecting the neutral to the ground makes the ground a live wire. Technically, it is possible to do that but highly discouraged. That is because people rely on the ground against fatal shocks as it works a path of least resistance.
In the case of a domestic setting where they use single-phase current, connecting neutral to the ground is a dangerous practice. If you do so regardless, instead of defending you from electrocution, the ground wire will be the reason for the electrocution. However, it is not an issue for industrial applications as they use a three-phase current.
To sum it up, you should not wire the ground and the neutral together. Regardless of the situation, it is not a good practice and is far too dangerous for a domestic setting. Therefore, if you want to avoid electrocution hazards, you must make sure that the neutral is not connected to the ground in any way.