Which instrument is specifically used for testing ground resistance?

The instrument specifically used for testing ground resistance is the earth resistance tester. This specialized device is designed to measure the resistance of the ground connection or electrode system to ensure that it meets safety standards. Ground resistance testing is critical for electrical systems to reduce the risk of electric shock and ensure proper system operation.

The earth resistance tester works by applying a known voltage and measuring the current that flows through the ground. From these measurements, it calculates the resistance. This functionality is essential because it evaluates the effectiveness of grounding installations, which can vary significantly depending on soil conditions and moisture levels.

While other instruments, such as voltmeters, amperemeters, and insulation testers, serve important roles in electrical diagnostics, they are not specifically designed for measuring ground resistance. A voltmeter measures voltage, an amperemeter measures current, and an insulation tester checks the integrity of insulation in cables and equipment, but they don't provide the targeted information that an earth resistance tester does.