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प्रश्न
What do you mean by the term local earthing? Explain how it is done.
उत्तर
Local earthing is made near the kWh meter. In this process, a 2 - 3 metre deep hole is dug in the ground. A copper rod, placed inside a hollow insulating pipe, is put in the hole. A thick copper plate of dimensions 50 cm × 50 cm is welded to the lower end of the copper rod, and it is buried in the ground. To create a strong earth connection, a mixture of salt and charcoal surrounds the plate.
To keep the ground damp, water is poured through the pipe from time to time. This forms a conducting layer between the plate and the ground. The upper end of the copper rod is joined to the earth connection at the kWh meter.
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