Earthing for Rocky Soil
Earthing plays a pivotal role in all the earthing installations made by the human. The reason being is an earthing or grounding system saves your electrical appliances being damaged by stopping the running current through the circuit. Not just it saves your appliances but it also prevents fire incidents that can happen due to the current leakage. Earthing engineers can easily install earthing systems in several areas except for a few problems areas such as rocky areas.
Earthing engineers usually have to face a lot of problems in installing the earthing system in rocky areas. All rock formations such as siltstone, limestone, millstone, granite & sandstone have high electrical resistivity which is a problematic thing when it comes to design or install a low voltage or high voltage electrical earthing system. There are numerous ways through which you can get low soil resistivity in rocky formations to get effective earthing.
Increasing soil moisture
One of the methods to adopt for an effective earthing is to increase the moisture of the soil on which you have to install the earthing system. Higher soil resistivity can be decreased by 800 ohm-m if you increase soil moisture from 5% to 10%. You can get an additional reduction in soil resistivity by increasing the soil’s moisture from 10 percent to 20 percent. However, adding moisture content to the soil is not always a feasible solution in most of the cases.
Treating the soil with salt
Another feasible option to decrease the earth’s resistivity is to treat the ground with salts such as magnesium sulfate, copper sulfate or sodium chloride. When the salts are combined with the moisture, they reduce the resistivity of the earth. However, this has its loopholes. The salts might wash away and the soil returns to its original condition. So, you need to recharge the system regularly. The salt can also contaminate the water of the ground and the local environmental protection agencies may object the process of adding salt to the earth.
Using Ground enhancement material
Another alternative to going for an effective earthing system for rocky areas is to use a ground rod in the soil. But you need to keep it in mind that the ground rod must go down the lowermost frost depth. Using ground enhancement material can also help you get effective ground in rocky areas. This material is perfect for the rocky ground where the limited space thwarts earthing installation with the help of conventional methods. Numerous ground enhancement materials can be used for this purpose. Some of the materials are coke powder, bentonite clay & specially engineered substances.