Electrical Ground Testing Procedure

In areas where driving ground rods may be impractical the two point method can be used.

Electrical ground testing procedure.

The procedures for earth resistance testing are referenced in ieee standard no. The first is the 3 point or fall of potential method and the second is the induced frequency test or clamp on method. The end user would use a test instrument and probes to first inject a current into the earth between a test electrode and a remote probe measure the voltage drop caused by the soil to a designated point and then use ohm s law to. Prior to about 15 years ago the basic methodology for ground testing remained fundamentally unchanged since it was originally devised in the early 20th century.

Ground testing is used to measure the performance of this circuit and check if it meets requirements. Download paper c the four potential method wenner method this technique helps overcome some of the problems associated with the requirement for knowing the electrical centre of the earthing systems being tested. Beyer wally electrical protetion grounding fundamentals pdf 1994 u s. Ground continuity testing ground continuity testing is the same concept as ground bond testing.

Standards procedures for testing the electrical ground system. However there are key differences between these two tests. Department of agriculture usda rea bulletin 1751f 802. Similar concept to the ground bond testing.

Neta world techtips ground testing in difficult installations by jeffrey r. The furthest ground probe needs to be at a distance that is 10 times the length of the ground rod. There are two 2 methods for testing an electrical grounding system. On modern electrical systems rcd s and rcbo s are regularly fitted these devices react to electricity missing from the circuit or installation such as when a person is receiving an electric shock as the electricity passes through his body to the ground earth.

Testing procedures have been also developed. The 3 point test requires complete isolation from the power utility. Not just power isolation but also removal of any neutral or other such ground. Purpose method a dc low current test to check circuit resistance.

2 point dead earth method. Inadequate electrical grounding or wiring on the customer s premises or. Ansi ieee std 81 1983 ieee guide for measuring earth resistivity ground impedance and earth surface potentials of a ground system. For instance if the ground rod is 8 feet 2 4 m long the furthest probe should be 80 feet 24 m away.

Four of the most common methods of ground resistance testing used by test technicians are discussed below. Insert 2 ground probes into the ground. You re simply checking for a continuous path on a ground circuit.