Final answer:
The main difference between system grounding and equipment grounding is that system grounding stabilizes voltage during normal operation and prevents unwanted voltage on accessible conductive parts, while equipment grounding provides a safe path for fault current and protects users from electric shock.
Step-by-step explanation:
System grounding involves connecting the system conductors to the ground, typically for the purpose of stabilizing the voltage to earth during normal operation. It is crucial in ensuring that the system operates safely by preventing unwanted voltage on conductive parts that people might come into contact with. The ground potential is often considered to be zero, which is similar to how sea level is treated as zero when calculating gravitational potential energy (PEg = mgh). This choice of a reference point simplifies the analysis of electrical systems.
On the other hand, equipment grounding provides a safe path for the flow of fault current when a short circuit or any fault occurs within electrical equipment. By connecting the non-current-carrying metal parts of equipment to the earth, the risk of electric shock is greatly minimized should the insulation fail. This ensures that any fault current is safely directed into the ground rather than causing harm to users or the equipment itself.
Grounding is a critical safety measure, both in system grounding and equipment grounding. While system grounding generally pertains to the overall electrical system's stability and safety, equipment grounding specifically deals with individual pieces of equipment and protecting users from electrical shocks. Both types of grounding complement each other to provide a comprehensive safety mechanism against electrical hazards.