Four Factors that can Negatively Impact a Boat's Electrical System

Posted on Jun 10, 2016 by Robert Iversrud
Electrical system

Even a sailing ship needs a good electrical system.

When you're on the water, an electrical failure can be annoying or even outright dangerous. Without electrical power, you might be stuck unable to navigate, use the radio, or even have lights on. If you want to ensure a good, safe time on the water, make sure you're addressing these factors before they become problems.

The Wrong Equipment

Simply put, electricity on water is a vastly different proposition from electricity on land. There's a reason an electrical system includes a "ground," after all, but when you're on the water, that takes on a very different meaning. Conventional electrical equipment will state there's a good ground simply because current is flowing into the water through the hull or other parts of the boat, for example. So use the right tools, like ohmmeters and voltmeters, for the job.

Similarly, make sure you're using the correct connectors, wiring, and other materials. The land is much more forgiving than the water, and using the wrong materials can blow out fuses, flatten batteries, and in many cases, start fires.


Watercrafts especially are in a constant war with the elements, and corrosion can quickly become your worst enemy. Salt is an obvious issue for seacrafts, of course. But even if you stick to fresh water, though, the constant humidity and other conditions will take its toll on your wiring. And what might happen if you get caught in a storm? Check your boat's electrical system for signs of damage before you take her out, every time, and ensure you'll have power when you need it.

Old Wiring

Electrical system

Enjoy the water without worrying about your electrical system.

Another problem, especially on vintage boats, is that the wiring is of a matching vintage. Even the best-kept boat will see some hard wear as it goes on the water, and as wiring ages and takes standard wear-and-tear, it develops more shorts, faults, and other issues. Before taking on the responsibility of a weathered boat, go through the wiring carefully and ensure that it can help you stay afloat in the first place.

Mismatched Power Sources

Older boats tend to operate on DC power, while newer ones have incorporated AC, but use direct current from batteries to provide the needed energy. Needless to say, switching from one form to the other, whether through converters or another solution, can put unneeded stress on a boat's electrical system, triggering breakers, knocking out entire systems, and generally causing havoc.

While less of an issue for newer boats, if an older boat has flickering lights or can only accept one item on at a time, look closely at the system for mismatching and other problems, especially as a poorly connected power converter is an ideal place for more complicated electrical problems to develop. And even on newer boats, make a point of looking closely at the grounding on your converter setup; stray AC current "leaking" into the DC ground system can be dangerous.

When you get a boat, whether it's new or new to you, make a point of going through and checking the wiring closely. Even a small body of water can be deeply unforgiving if you lose power at the wrong time. And if you need quality parts, start with our wire and cable products.