Soil Resistivity Testing Services

Making Sure that Grounding Systems Work Effectively

ETTL has been helping clients make sure the grounding systems they are designing (or have already installed) will be compatible with the soil in which they are placed.

Almost everyone recognizes the importance of earth grounding for electrical systems -- the need to provide a low-impedance path to the earth for high currents from lightning strikes and power surges, as well as a path for low currents from RFI (radio frequency interference) and static build-ups -- and also to ensure that non-current carrying metal parts are at ground potential for the sake of personnel safety. What is not as well known is that soil resistivity (electrical resistance of the subsurface) varies widely, often within the same site, depending on soil type and density as well as depth. A soil resistivity "profile" can be crucial to grounding system design. If soil resistance is too high, the system may fail, resulting in loss of (or damage to) highly expensive electrical equipment, such as exists in TV towers, cellular towers, water towers, electrical billboards, elevator electrical systems and other types of installations.

In addition, knowing soil resistivity is important for control of corrosion in buried structures.

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