To increase the safety factor of installation, two copper wires are used as earthing lead to connect the device metallic body to the earth electrode or earth plate. I.e. if we use two earth electrodes or earth plats, there would be four earthing leads. It should not be considered that the two earth leads are used as parallel paths to flow the fault currents but both paths should work properly to carry the fault current because it is important for better safety.

In our electrical appliances, if excessive currents are not earthed, we would experience severe shock. Earthing takes place in electrical appliances only when there is a problem and it is to save us from danger. If in an electronic installation, a metallic part of an electrical appliance comes in direct contact with a live wire that results from maybe failure of installation or otherwise, the metal will be charged and static charge will accumulate on it.

I have seen a person killed simply because a live wire got cut from overhead pole and fell to the ground while the ground was wet. Excessive current is earthed at generating stations and if at all the earthing is not efficient due to fault, earth fault interrupters will be there to help. Fuse help only when the power transmitted is above the rating of our appliances, it blocks the current from reaching our appliances by blowing off and protecting our appliances in the process.

نحوه نصب به این صورت است. که ابتدا شما موقعیت و شرایط محیطی خود را از میان دو روشی که گفته می‌شود انتخاب کنید. دو روش موجود برای انجام ارتینگ عبارت می‌شوند از روش زمین عمقی و روش زمین سطحی که در ادامه به توضیح هر دو می‌پردازیم.

However, if excessive current is not earthed, appliances will be damaged without the help of fuse in place. You should note that excessive current are earthed at their generating stations which is why earth wires carries very little or no current at all. It therefore implies that it is not necessary to earth any of the wires (live, earth and neutral wires) contained in a PVC. Earthing the live wire is catastrophic.