Mobile QR Code QR CODE : Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

ISO Journal TitleJ Korean Inst. IIIum. Electr. Install. Eng.
Title Characteristics of Grounding Impedances of Carbon Compound Grounding Electrodes
Authors Kang-Soo Lee ; Bok-Hee Lee
DOI http://dx.doi.org/10.5207/JIEIE.2011.25.5.054
Page pp.54-60
ISSN 1225-1135
Keywords Carbon Compound Grounding Electrode ; Frequency-Dependent Grounding Impedance ; Transient Grounding Impedance ; Conventional Grounding Impedance ; Grounding System
Abstract This paper presents characteristics of frequency-dependent grounding impedance and transient grounding impedance for the carbon compound grounding electrode used in the installation of computerized electronic equipment and lightning protection system. The frequency-dependent grounding impedances were measured by applying sinusoidal currents in the frequency range from 100 [㎐] to 10[㎒], and the transient grounding impedances were examined by subjecting the impulse current with the front-time between 1∼80[㎲]. As a result, the ground resistance of the carbon compound grounding electrode is less than that of another type grounding electrodes. The transient grounding impedance is relatively low and the conventional grounding impedance is rather lower than the ground resistance. The frequency-dependent grounding impedance of the carbon compound grounding electrode is capacitive and the grounding impedance is decreased with increasing the frequency of injected currents. Therefore in the case that the carbon compound grounding electrode is jointly used with large-scaled grounding electrodes, it is possible to reduce the high frequency grounding impedance of the integrated grounding electrode system.