Electronics & Software – Tips & Guide


What is a neutral wire?

What is a neutral wire?

For any circuit to work, there must be a complete circuit from the power supply to the load (light, appliance, heater, etc.) and the power supply. the return wire is usually labeled neutral and can be connected to the ground, in which case it has zero volts to ground (and you). If a center tap is connected to ground at the center tap, the neutral will have a supply voltage of 50% of the ground.

no neutral, no complete circuit. circuit will not work.

for dummies:

the live line carries energy and changes the polarity from a negative voltage to a positive voltage.

the neutral line transfers the load to the ground or to the plant.

If you place something (such as a toaster) between the live line and the neutral, the current will flow.

If you touch the neutral, since it is not powered, you will not be shocked.

security warning for dummies:

do not touch the neutral.

If your house is not wired correctly, the neutral could charge and hurt you.

does not break the neutral.

Even if there is no voltage, the current always flows in the neutral line. if you break the connection, the current will shock you and hurt you.

Do not play with electricity if you do not know what you are doing.

it could hurt you

A neutral wire that is usually designated by a black color provides the return path for the current provided by the phase. this current flows in phase and passes through the equipment goes to neutral, thus providing a closed loop and completing the circuit and allowing the current to flow. the neutral must not be misinterpreted as earth these two things are totally different, the earth is the third wide pin provided in the top of the plug to allow any leakage current to pass to the ground and thus avoid shocks. Although the Earth can act in a neutral way because it is considered as a large body with an infinite positive charge, but this practice is very dangerous because if the system underwent a surge, it would not react and would not let the current flow, this which would give him complete power. the path causing damage to the equipment while if the proper neutral is provided, it will act with the system and prevent the equipment.

First, a neutral wire exists only in the North American standard system. In Europe, with their 220V systems, there is no neutral wire.

Second, in North American systems, where the secondary winding of the power transformer is connected and grounded and routed throughout the system as a neutral wire, its purpose is to carry back current unbalanced loads (220) such as a 10 amp 110v toaster on one side of a separate receptacle and a 6 amp mixer 110v on the other side. in this case, 6 amps circulate from one 220 volts step to another without using the neutral. the remaining 4 unbalanced amps requested by the toaster run from one leg of the 220v circuit to the neutral only, then return to the center point of the transformer winding on the neutral wire.

a neutral line is necessary because of the practical issue. the earth is used as a return path for unbalanced circulation currents only. Although mass has zero potential, if all devices in a locality are connected to land as a return path, in that area or locality, household currents can infiltrate another household. during a breakdown. if there is a short circuit fault in your house, your neighbor’s currents will begin to feed your fault through the ground. it is highly undesirable. In addition, the underground network of the Earth consists of steel pipelines. these currents interact with such metal pipelines and induce electromotive forces, causing a huge loss of eddy current. and imagine the whole locality filled with underground water or sewers. all these conditions provide a path of low resistance to current, thus acting as parasitic loads. therefore, the current is taken if a neutral path for the return, and the ground is used only when the conditions are defective.