Getting Down to Earth 19Equipment can also be damaged similarly by overvoltages caused by high-resistance ground systems. Factors Influencing Requirements for a Good Grounding SystemIn an industrial plant or other facility that requires a grounding system, one or more of the following must be carefully considered (see Fig. 8):1. Limiting to definite values the voltage to earth of the entire electrical system. Use of a suitable grounding system can do this by maintaining some point in the circuit at earth potential. Such a grounding system provides these advantages:n Limits voltage to which the system-to-ground insulation is subjected, thereby more definitely fixing the insulation rating.n Limits the system-to-ground or system-to-frame voltage to values safe for personnel.n Provides a relatively stable system with a minimum of transient overvoltages.n Permits any system fault to ground to be quickly isolated.Fig. 8: Typical conditions to be considered in a plant ground system
