Final answer:
Grounding connects a conductor to the earth, setting it at zero volts for safety. Effective Ground-Fault Current Path ensures low-resistance path for fault current, so protection devices can interrupt it. Calculations using Ohm's Law determine whether a circuit breaker will trip in a fault scenario.
Step-by-step explanation:
General Requirements for Grounding and Bonding
In the context of electrical engineering, grounding refers to the practice of connecting a conductor to the earth, setting it at zero volts, which is essential for electrical safety. The concept of an Effective Ground-Fault Current Path is critical—it ensures that if a short circuit occurs, such as a fault to the grounded metal case of an appliance, the fault current has a low-resistance path to earth. This protects against electrical shock hazards by allowing circuit protection devices, like fuses or circuit breakers, to quickly interrupt excessive current.
For example, if 5.00 mA flows through a person who has a 3.00 kΩ resistance to ground, the voltage on the case can be calculated using Ohm's Law (V = I * R), resulting in 15 volts. Considering the earth/ground wire resistance of 0.200 Ω, the short circuit current can also be calculated (I = V / R). However, given that such a fault current is likely to be higher than the 5.00 mA passing through the person, it may not be enough to trigger a 20.0 A circuit breaker, depending on the total resistance in the fault path. This showcases the importance of correctly sized protection devices and appropriate grounding in the system.