Marine Electrician vs Regular Electrician Cont….

Boat Electrical System Components


While we make our income dealing with the repair of boat wiring, I believe it is important to educate boat owners about marine electricity so that they are safe and their investment is protected.

I have seen some very scary jury-rigged wiring that literally looked like a rat’s nest and just so happened to have rat’s in there and wasps to boot! That’s scary stuff and also almost begging to cause a fire. So, let’s talk about parts of marine electrical systems.

I talked before about grounding and the difference between AC & DC. There is only 1 point where DC is grounded, at the battery. It is a free floating system where nothing is ever grounded to any metallic part of the vessel, most especially not the bonding system. It’s like a car sitting on rubber tires which provide insulation, the battery itself provides a negative potential.

Bonding Systems

These actually have nothing to do with electrical systems. Nothing should ever be grounded to bonding systems. Unskilled electricians often make the mistake of using this to ground electrical systems and this often ends in disastrous results.

Electrolysis & Galvanism

Boaters who don’t really understand electrolysis often abuse this work. Number one, all boats have electrical potential. All the metals on the boat have differing electrical potentials. This is exactly the principle that allows a dry cell battery to generate electricity. This electrical potential is called galvanism & is the reason why we put zincs on boats.

Now, electrolysis is stray current escaping and is most damaging. When this occurs, it eats up zincs quickly and leaves it looking bright & shiny. So, Shiny zincs = electrolysis & Dull eroded zincs = galvanism.

Shore Power Cords

The largest cause of issues w/ shore power systems comes from failure to maintain connectors on both the cord & boat connectors. Remember, these are exposed to water & will suffer from corrosion & general wear. This can eventually result in overheating & power drop. This alone can create conditions for fires & cause electrical equipment to work harder which reduces the life span of your boat. Maintain your shore power connections!

Coastie Marine recommend you buy only the highest quality power cords, as these will last longer and have the advantage of replaceable connector parts. Cheap connectors usually can’t be taken apart. Lastly: If you’re not turning off the dock breaker before disconnecting the power cord, start doing it! You risk getting electrocuted, but disconnecting an energized connector damages the contacts.

Please feel free to email us if you have any type of electrical questions at or check out our website:

Thanks! Cliff Hairston, Owner/Marine Electrician


MARINE Electrician vs Regular Electrician

Discussion about marine electricians only to work on your vessel.

Marine Electrician vs. Regular Electrician

If you own a boat, you are aware that insurance companies use marine surveyors to inspect your boat before they insure you. One of the top issues these surveyors run into are electrical systems that have been jury-rigged. This usually happens when you use “Bob the Electrician” from down the road because his rates are cheaper. Some of these guys think wiring a house is the same as wiring a boat but that is absolutely not the case.

The older the boats get, the more jury-rigged wiring occurs and ends up causing a substantial number of problems. I’m not mocking residential & commercial electricians but substandard boat wiring can cause problems to your entire system, such as, chronic battery drain, frequent system faults or even electrolysis and fires. And not to mention a long list of fixes from the marine surveyor.

So, why does using a MARINE electrician so important? Well, most importantly is that your boat is in the water which makes a boat much different than a house or car. Sea water is a fair conductor of electricity. There are addition rules about materials & methods of installation that you won’t find on land based vehicles or buildings. Water provides an awesome ground path for electricity so we must be careful how things are completed.

Many marine electricians are self-taught as there are little vocational schools for this career. I was lucky enough to receive exceptional training in the U.S. Coast Guard. So, when hiring a marine electrician, experience and training is key so I would ask for credentials, or a resume or anything that provides proof of knowledge in this field.

Materials and equipment are much different in the marine repair industry. The ABYC or American Boat & Yacht Council has strict standards for this as does the U.S. Coast Guard. Do not use common wire or wiring devices or residential electrical equipment. If proper materials are not grounded, properly constructed or insulated, you might be at a high risk for fires.

One of the most horrible things I’ve seen on a boat is the use of extension cords, non-marine wire, audio speaker wire and even household lamp cords. This is not a joke at all. House wire and marine wire is completely different. Marine wire must have the right temp, be water & oil resistant & should be purchased from a reputable marine supplier.

No one who is untrained in marine high voltage systems should touch boat wiring. Deadly fault systems are too risky. Grounding & a boat’s electrical system most commonly misunderstood. Only someone educated in AC & DC marine grounding should touch boat wiring. AC & DC are two separate systems. If you don’t know the 4 principles of ground systems, stay away from boats. And owners need not hire.

In the next article, I will discuss the main parts of a boat’s electrical system and further stress the importance of hiring a marine electrician vs. any old regular electrician. Moral of the story is that you will actually save money in the long run and have peace of mind using a skilled and trained marine electrician on your boat. Protect your investment.

Cliff Hairston, Owner/Marine Electrician or Facebook: @coastiemarine



Let’s Learn about Parts of Your Boat

Hey, not everyone was raised on the water or in the Coast Guard or Merchant Marines, that’s just a fact. While I make a living off of people who do not know these things, I would still find myself unable to sleep at night knowing there were boaters out there who didn’t know the basic parts of a boat. Let’s Review!

  • The Hull and the Keel
    • The hull of a boat is an internal framework that extends from side to side (transverse) & also runs the length of the boat (longitudinal). The hull is covered by an outer shell plating, most often constructed of fiberglass or metal. All boats also have a keel: the backbone of the boat that runs along the center bottom of the boat & provides stability in the water.
  • Starboard, Port & Gunwale
    • When operating a boat, the starboard side is the right side of the boat & the port side is the left. The gunwale is the upper edge of the sides of a boat.
  • The Bow, the deck & the stern
    • The front of a boat is the bow & its curved shape is designed to the lift the vessel w/ waves, rather than cutting into them. The stern is the back of the boat: a flat, square stern has a broader surface for a wave to act upon compared to a round stern. The round, or cruiser stern, is safer in following seas because the wave splits & travels forward along each side of the boat. The deck is the upper surface of the boat. The curvature of the deck allows water to flow off of it.
  • What is the Sheer, Flare & Tumblehome
    • The curvature of the deck from bow to stern is the sheer, which along with the flare & tumblehome determine a boat’s displacement & buoyancy. Flare increases displacement, and is the outward turn of the hull as the sides rise from the waterline. Tumblehome, the reverse of flare, is the shape of the hull from the gunwale to the waterline.
  •  What are your Chine & Beam?
    • The part of the boat that is below the waterline is the chine and it determines your boat’s speed & how it handles on the water. If the chine is rounded, it is a soft chine. If it squared off, it is a hard chine. The beam is simply the width of the maximum width of the boat.
  • What’s the Rudder & Propeller?
    • The rudder steers the boat, which is driven by one or more screw propellers. Propellers rotate & power a boat either forward or backward. These parts of the boat are at the back and located underwater.

That concludes Coastie Marine’s boat part lecture for the day. Don’t feel bad if you didn’t know all these words because now you do! And I feel safer being out there with you having a little bit more knowledge of the craft you are driving! If you have any more questions or need any boat repair of any kind, feel free to call me anytime, 850-896-9147 and I’d be happy to help!