• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.426-429
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• 1999

In this paper, we have provided the measurement technique of the grounding mesh resistance by field measurements. The standard of measurement is specified in the IEEE Std 81.2-1991 and JEAC 5001-1988, which is the the fall-of-potential method by test-current injection, but this method is difficult to apply at field, where is small around a electric power substation of domestic. For the convenient measurement method, space of assistant probe and quantity of test-current injection are changed step for step. As the result, ' the proposed measurement technique of grounding mesh resistance is that the space of current and potential probes must be fixed at 150rn from a grounding mesh, the test-current injection has to keep 5A or more.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.311-314
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• 2009

This paper presents the characteristics of grounding impedance of counterpoises buried at various soil structures. Grounding impedance measurements were made by the Fall-of-Potential method. The experiments were carried out in 50 m counterpoise of 25 $mm^2$ buried at a depth of 0.5 m. The test current was injected by the impulse generator having the front time of $1{\sim}60{\mu}s$. As a result, the soil structures greatly influences on the grounding impedance characteristics of counterpoise. The transient grounding impedances strongly depend on the injection mint and the front time of impulse current.