Safety Ground
The ground wire connects to earth ground and is not part of normal circuit.
The safety ground routes stray voltage to ground to protect people and equipment.
When stray voltage is routed to ground, the fluctuation in voltage causes the circuit breaker to trip.
The breaker opens the circuit and stops the flow of electricity.
The wires involved in power problems classify wiring problems.
The two types of wiring problems are common mode and normal mode.