Change List for this Rule


General Order 128


Section II


Definitions of Terms as Used in These Rule

21.5     Grounded means connected to earth by a conductive path.


A.     Effectively Grounded (Effective Ground) means permanently connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current–carrying capacity to prevent the building up of voltages which may result in undue hazard to persons or to connected equipment.


If an impedance of less than 25 ohms is not obtained, the equivalent of a ground conductor not less than #6 AWG copper connected to two corrosion resisting rods, not less than 1/2” in diameter and 8 feet in length and continuous throughout, driven to a minimum depth of 8 feet in the earth at not less than 6 foot centers, will be considered an effective ground for the purpose of these rules.


Note:     Revised October 9, 1996 by Resolution SU–40.