Testing & TroubleshootingQuestion 498 of 521
In a properly bonded system, what is the primary purpose of the equipment grounding conductor during a line-to-enclosure (ground) fault?
a.To carry normal load current back to the source
b.To provide a low-impedance fault-current path that lets the overcurrent device trip quickly
c.To improve power factor
d.To limit voltage drop on long runs
Explanation
The EGC's job on a fault is to give fault current a low-impedance path back to the source so enough current flows to open the breaker/fuse fast, clearing the fault and de-energizing the enclosure. It does not carry normal load current (that's the neutral, a), and it has nothing to do with power factor (c) or normal-load voltage drop (d).
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