Selecting a Ground Resistance Meter on Amazon.com
A ground resistance meter tests the grounding of electrical systems and equipment by measuring the ground resistance value in ohms. Proper grounding is essential to protect people from electric shock; prevent service interruptions, damage to electrical equipment, and intermittent electrical problems; and safely dissipate lightning strikes, static discharges, and electromagnetic or radio frequency interference. Safety standards set by agencies including OSHA, NFPA, TIA, and IEC require grounding systems testing.
Ground resistance meters are used for design, construction and maintenance applications at commercial and industrial sites, electrical substations, and microwave and radio towers. A ground resistance meter may be able to perform four different types of earth ground measurement: 4-pole soil resistivity measurement for designing new grounding installations; 3- or 4-pole fall-of-potential to measure a system or electrode's ability to dissipate energy; stakeless or clamp-on to measure ground loop resistance without disconnecting the ground; and selective, which uses both poles and a clamp.