Why stones are layed in switchyard or in power stations?


Reasons for using Stones in Switchboard Yard / Substation :

Power Transformers installed in the substations will have oil as cooling and insulating medium.Oil leakage takes place during operation or when changing the oil in the transformer. ... So Stones is provided to protect from fire when oil spillage takes place.

View of Technical : 

1.To avoid rain water to stand on ground, to prevent the growth of grasses & plants,growth of plants & grass near the yard cause will create the short circuit .

2.The most important point to avoid step potential and touch potential to rise.where step potential is potential between human body & touch is potential between human body & equipments. 

3. keep the moisture always bottom  of the stone to reduce the earth  resistance

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