Originally Posted by SVAuspicious
I'm not clear on the value of separate circuits for each outlet.
Auspicious has port (8 outlets) and starboard (4 outlets) circuits, a water heater circuit, and a battery charger outlet on the main 30A inlet. The A/C 30A inlet has forward and aft A/C unit circuits and an A/C circ pump circuit plus an independent electric heater outlet.
Because if you string 3 outlets on a single, 15 amp branch breaker, you can only run a cumulative 15 amps on all of the outlets. That means you can only run a single 1500w heater, and basically the other two outlets are useless because there is no spare capacity on the 15 amp breaker.
I only have 3 outlets on my 30 foot boat, but they are all on separate 15 amp branch circuits, and since they are all individual and not daisy-chained, they are ALL GFCI outlets. This gives me the ability to pull 30 full amps from at least two outlets and not trip the mains breaker.
Please understand that when I say "15 amps" and "30 amps" I'm not including the 20% safety buffer that you're supposed to build into your circuits. You're only supposed to pull 24 continuous
amps through your 30 amp mains breaker and 12 continuous
amps through a 15 amp branch circuit breaker.
I'm sure that Auspicious knows this, but for readers who are contemplating installing shore power, or new liveaboards, the 20% safety buffer is important to avoid wiring meltdowns that won't trip the circuit breakers. This is referred to as "boiling the frog".