When you receive the electrical current from the utility company, you are receiving a single phase 240 volt. In order to use this in your home and receive 120 volts, the voltage is split into two by way of a center tap that is called a neutral wire. Some call this wire the grounded conductor. The wire is attached to the water main or even an electrode, then to your electrical panel. This grounds your electrical items. The grounding wire is the safest way to protect your property from fire and to prevent electrical shock. If your appliances or electronics are not grounded, the current will travel through the stray path to cause an electrical shock.
The neutral wire is white and carries the current away from the electrical item. If you do not hook this wire up correctly, you may have a potential hazard for a fire or shock. The earth wire as it is also call must be grounded to the water main or electrode. If you do not know about grounding or about doing this properly, you should have a professional electrician or electrical contractor come in and ground the current before you try to use anything. No home or other building should use any electrical current without proper grounding.
Neutral wires are for grounding and nothing more. They protect you from possible injury and protect electrical equipment from any stray current that comes into the home. Keep in mind that most neutral wires are white, but in some cases, they may be a grey color. This is true for the United States and not for the UK or other countries where the neutral wire is a different color. If you have any doubts, you should call an electrical contractor for your wiring needs. Electricians are insured and licensed in this type of work to prevent injury and other hazards to your home or you.
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