Grounding

Introduction

       Electrical grounding originally began as a safety measure used to help prevent people from accidentally coming in contact with electrical hazards.
        For measurement purposes, the earth serves as a contact potential reference against which other potentials can be measured. An electrical ground system should have an appropriate current carrying capability to serve as an zero voltage reference level. Where a real ground connection has a significant resistance the approximation of zero potential is no longer valid.
         Ideally a ground should be of zero ohm resistance.There is not one standard ground resistance threshold that is recognized by all agencies.However the NFPA and IEEE have recommended a ground resistance value of 5 ohm or less.
Importance of Ground for a Generator

       Generator system must have proper grounding of all electrical components and transfer switches to minimize the possibility of uncommon current flow resulting in a power outage, damage to equipment or injuries to personnel.

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