[paulie_w]

Wiring and terminations are the means to get power delivered to the various bits of electrical equipment on our boats and it is termination points in particular that cause the vast majority of problems. Matching terminal size to wire gauge (wire diameter) is important. Also, using the proper tools to strip insulation and then crimp on the terminal is imperative to minimize potential problems. The tool kit I use for these tasks is shown in Figure 5. For more on using good electrical tools, see: Marine electrics: how to use good terminals and tools.

[edgeleyx]

Understanding how a typical marine 12-Volt system actually works will make the back of the switchboard a much less scary place. [links]

[dmytrij]

A multimeter will be your main diagnostic tool when it comes to troubleshooting your DC system. This is definitely an area where spending a little bit more money up front will pay off in the long run. My favorite multimeter for beginning electricians is the Blue Sea model 8110. It measure volts, ohms, and amps in both AC and DC values, and offers a degree of sensitivity that meets the needs of the average, and even some not-so-average troubleshooting situations.

[biohacker]

For example, sometimes a tripped circuit breaker can be the only reason the circuit isn’t functioning. If it’s tripped by accident or a one-time event, it can be simply reset. But usually there’s an underlying cause for the breaker to trip that will need to be found and repaired.

[nikitakit]

When marine electrical systems are working well, they are invisible to most of us – just like the electrical current itself. But it is this very convenience – the invisible power that does so much of the daily drudge work in the background – that is also what makes the system so daunting when things go wrong. Understanding the elements that need to be in place for a set of 12-Volt circuits to function safely, could not only help you prevent a short circuit or an overheated wire – both of which are fire risks on board – but will also permit you to venture much further afield without sacrificing the comfort and security that modern 12-Volt systems can provide.

[AStephen2011]

In the case of multiphase chargers, the voltages and battery-type selector switches all need to be set according to the directions that come with units. As for engine alternators, most have internal voltage regulators with fixed settings, so just make sure the maximum output doesn’t exceed your battery manufacturer’s specifications. Typically gel-cell type batteries are the most sensitive here.
[links]

[Guybrush]

Volts x Amps = Watts (example: 12 volts x 6 amps = 72 watts) more

[alexg]

For example, sometimes a tripped circuit breaker can be the only reason the circuit isn’t functioning. If it’s tripped by accident or a one-time event, it can be simply reset. But usually there’s an underlying cause for the breaker to trip that will need to be found and repaired.
[links]

[icaro]

Wiring and terminations are the means to get power delivered to the various bits of electrical equipment on our boats and it is termination points in particular that cause the vast majority of problems. Matching terminal size to wire gauge (wire diameter) is important. Also, using the proper tools to strip insulation and then crimp on the terminal is imperative to minimize potential problems. The tool kit I use for these tasks is shown in Figure 5. For more on using good electrical tools, see: Marine electrics: how to use good terminals and tools. [links]

[rufio1]

Aside from gauge size, wire type is also an important consideration. Marine grade cable contains more copper than automotive cable and the copper is also tinned, which makes it more corrosion-resistant in the marine environment.

[kldunc]

The fuse on the right complies with stringent European regulations, but might raise an alarm with an American surveyor. [links]

[kenlefeb]

After more than 40 years in the marine industry, I’ve had the opportunity to work on and inspect a lot of boats. In the area of electrical installations, where I’ve spent most of my time, I’ve seen plenty of common mistakes, made either at the factory level or by aftermarket installers. Remembering that the most common cause of onboard fires is a fault in the electrical system, it’s worth a look at what some of these faults are, and how they can arise. more

[piotrp]

The terminal shown center-left is so overloaded that the nut threads are half-exposed.

[PinkyCandice7x]

An expert in marine electrical systems—and the boats they’re installed in—highlights issues that should be kept in mind by any boater who has electricity on board.

[pjeromehaydeny]

Yellow arrows point to areas of concern in this battery installation: uncovered terminals and fuses that may be substandard. more

[lusid]

Chafe and wear are also important considerations in marine wiring. Boats move, repetitively and sometimes violently. Constant rubbing or bending can chafe away insulating coatings on wires and create short circuits. Repeated strain on connections can cause them to snap. here

[blackdresses]

State Licensing

[peex71]

Stray current can easily be conducted into the water around a ship. With high voltages, this can shock and kill nearby swimmers. With lower current levels, it can quickly corrode metal parts of a hull exposed to the current—a process known as galvanic corrosion. more

[dave]

Dealing with Water Incursion more

[cdnbcguy]

Since boats are usually disconnected from the electrical grid, marine electricians spend a lot of time working with generators and other alternative power sources such as:

[namkeeno]

This may look something like this:-

[alanahbing142]

The diagram for a split charge relay is shown below [links]

[imanikin]

Navigation instruments say 0.5 amp 24 hrs 12 Ah