by Frank Waterer, F.E. & Bill Brown, P.E.

This paper presents the fundamentals of power system grounding, fundamental definitions and NEC requirements for grounding, the need for LV ground fault protection and implementation, and special grounding requirements imposed by the data center operating environment. Also addressed are requirements for 4-wire versus 3-wire systems, installation of modified differential ground fault (MDGF) protection systems, and the effects of system grounding upon surge protection and power quality.