Typical Shore Power Wiring Animation
In Figure Five, we illustrate how things should work. In our illustration a boat called "Problem" is wired in accordance to ABYC recommendation and every thing is in good working order. The captain of the "Problem" plugs in his 1000 watt (8.33 amp, I=P/E)) toaster oven. Phase current of about 8.33 amps at line voltage (120 volts) would flow from the marina's power source through the pedestal, shore power cable, distribution panel, 15 amp circuit breaker, to the branch circuit and grounding receptacle supporting the toaster oven. The toaster oven in this case, places a load or resistance of about 14 ohms (R=E/I) on the circuit. The line voltage would drop to a low voltage (near zero) as it pushes the current through the 14 ohms load. The 8.33 amps of current at a very low voltage would now travel the "neutral" wire back to its source - ground.