When you leave your boat for an extended time or even shorter periods, leaving the power set up properly when you are gone can be very important. The key issues include keeping bilge pumps operative, keeping refrigerators and heating systems functional, keeping the batteries charged and mitigating any fire risks.
As is always important, dock power connections need to be kept dry and clean and clear from anything that might pull on them. However, power losses can come from outside sources. If you lose dock power, what does that do to your inverter and charging systems? Inverter systems and charging systems need to be set so that if dock power is out for an extended time, draw needs to be minimized and used for critical systems only. Power settings need to be set to ensure that a sudden surge of power when it is restored will not pop breakers.
When dock power comes on after a lengthy outage, any use of house 110AC in excess of heavy battery charging can cause either the boat’s or the dock’s breaker to pop. In that scenario, even though there is dock power, the boat has no power on board, since its breakers have popped.
Even our old 1995 Heart Inverter system allowed the On button to be switched quickly three times, so that if dock power was lost, it would no longer invert any power to AC outlets, which means if we leave an AC-powered device or a couple of lights on, they will not drain our house batteries while dock power is off. That’s very important! Of course, most boats with air conditioning or electric water heaters are wired such that they can get AC power only from dockside power or a generator.
Also consider that when dock power returns, the sudden heavy charging of batteries combined with other sudden AC requirements can pop either the dock breaker or the boat breaker. Inverters that also act as chargers usually have a setting that determines how many amps of maximum current can flow. Our older inverter also has toggle switches behind the main switch to set maximum charging amps, which helps if we are at a dock with 15-amp power. We can adjust accordingly.
The ramifications of drained batteries can mean damaged batteries, spoiled food in a refrigerator, non-armed alarm systems, no heat circulation and inoperative bilge pumps.
Solutions to these concerns are manifold. Most important is to understand how your inverter works in terms of not tripping either dock box breakers or your own boat’s breakers if power is lost for an extended period and then pops on.
Finally, have an AC lamp on your boat that only works when you have working dock power. Then your neighbors or marina workers can quickly check for you if all is OK after a power outage.