Citation

Hopkins R. Coal Age 2006; 111(11): 36-39.

Affiliation

Zero Ground

Copyright

(Copyright © 2006, Mining Media)

DOI

unavailable

PMID

unavailable

Abstract

Zero Ground System, an approach to reduce high frequency ground currents, which are produced due to the use of variable frequency drives (VFD) with motors in mines is discussed. Zero Ground, a new system solution for grounding, which reduces ground currents to zero while reducing motor bearing currents, extends motor life and minimizes crosstalk between adjacent cables. The method reduces stray capacitance and inductively coupled energy, directs fault currents away from hazardous locations, and eliminates both motor-to-frame and adjustable speed drives (ASD)/VFD-to-frame voltage to ground. In mines, Zero Ground addresses the safety and interference issues by reducing high frequency ground currents and provides the elimination of electrical shocks, sparks, and arcing. The mine safety and health administration (MSHA), in October, 2002, tested various Zero Ground system solution installations for the evaluation of potential benefits.