What type of equipment would indicate the amount of resistance presented to current flow by the equipment ground?

What type of equipment would indicate the amount of resistance presented to current flow by the equipment ground?

• A. Ground impedance tester
• B. Voltmeter
• C. Ohmmeter
• D. Megger

Answer: (A)

Measuring how much resistance the equipment grounding path presents is about the grounding system’s impedance to fault current. A ground impedance tester is designed for this purpose, injecting a signal and measuring the resistance of the entire path from the equipment to earth. It gives a direct readout of how well the grounding system will carry fault current, which is what you need to know to ensure proper overcurrent protection trips quickly. A voltmeter only measures voltage and doesn’t provide resistance information on its own. An ohmmeter tests resistance between two points in a circuit when isolated, but it doesn’t reflect the real-world impedance of the grounding path to earth. A megger checks insulation resistance by applying a high voltage and measuring leakage, not the resistance of the grounding path itself.

Measuring how much resistance the equipment grounding path presents is about the grounding system’s impedance to fault current. A ground impedance tester is designed for this purpose, injecting a signal and measuring the resistance of the entire path from the equipment to earth. It gives a direct readout of how well the grounding system will carry fault current, which is what you need to know to ensure proper overcurrent protection trips quickly.

A voltmeter only measures voltage and doesn’t provide resistance information on its own. An ohmmeter tests resistance between two points in a circuit when isolated, but it doesn’t reflect the real-world impedance of the grounding path to earth. A megger checks insulation resistance by applying a high voltage and measuring leakage, not the resistance of the grounding path itself.