Utilize Deep Well as Earth Pit

Engineering practice is to get the results economically as well as in a convenient way otherwise the hypothetical method adopted by the contractor which gives the desired earth resistance test values is acceptable.

Standard practice is that separation between any two earth electrodes as a minimum be equal to the length of earth electrode itself.

Vertical earth rods can be hammer driven in ground or lowered in bore holes.

When the contractor is drilling 20 to 40 meters but is restricting separation to 10 meters he is actually undermining his efforts.

Sorry, I should be better to focus on the major issue only.

My question is how it is practical to bore a 20 or 40m well to earth for an earthing system. Here, I will not mention about the length of trench.

Such deep drilled earth electrodes are normally practised in Rocky Terrains.

The Victoria Centre in Nottingham, UK uses this method. The 24-story tower is built on dry sandstone. Wells had to be sunk for each of the two utility substations.

You may find this interesting http://www.cpccorp.com/deep.htm

dear ,

YES. The method suggested is the ultimate in Earth Electrode technology.

This is 1000 % Gaurranteed for life - stability of earth results & even Earth Resistance Values.

When the normal method of earthing fails, say in rocky areas, this may be used. But if you compare the cost of installation & material, the suggested method proves very costly.

2. I have seen in remote Sub station areas in forests rocky soil, where normal earth values were 11 ohms to 30 ohms !

By adopting the above suggested method, we have seen the resistnasce values come down to 0. 8 Ohms. to 1.2 Ohms

Normally, the requirement jumps from 4ohm to 10ohm. With this method, the resistance sometimes comes down to <0.8ohm and relatively stable through the year.

So, after the contractor finished the work, they can wait for month for the inspection and handover while the earth resistance remains the same.