Measurement by voltage drop method

Grounding Consulting

Measurement by voltage drop method

The measurement of the ground resistance of a large-scale grounding body, such as a structure grounding, requires the measurement of the ground resistance by the voltage drop method.

Necessity of measuring ground resistance by the voltage drop method

Necessity of measuring ground resistance by the voltage drop method

In the measurement of large-scale grounded objects such as structure grounding, a ground resistance meter causes potential interference between the measuring electrodes and finally errors in the measured values.
Therefore, the voltage (potential) drop method is used by installing the voltage electrode (point P) and current electrode (point C) with a long distance between them not to be interfered.
Since a large current of about 10 to 20 A is applied for measurement, it is essential to take sufficient safety measures.

Measurement object

Large-scale grounding electrode
  • Grounding electrode using a structure ※1
  • Ring-shaped grounding electrode
  • Mesh grounding electrode ※2
  • Foundation grounding electrode
  • Mandatory in the Building Equipment Design Standard (2008 edition)
  • Power generation and transformation regulations JEAC5001-2012

Determination method

Determination method
Measuring instrument

Measuring instrument

Temporary auxiliary grounding electrode

Temporary auxiliary grounding electrode

Features

  • Conduct measurements based on regulations
  • Support based on the measurement results
  • Determination of applicability of structure grounding and proposal of countermeasures
  • Application for the allowance of road use when measuring and taking safety measures
  • Nationwide support