Artefact2
08.06.2021 22:22:18
Does current travel through the water from boat to boat? No, it doesn’t. Only via the grounding system. [links]
See full version: Corrosion in Marinas
Does current travel through the water from boat to boat? No, it doesn’t. Only via the grounding system. [links]
What happens when there is a fault in the neutral ground? Your lights are dim and electrical appliances run slower, and eventually burn up. You will get lower readings when you measure the voltage.
Will my panel meters reflect the problem in any way? Usually not, although if there is a ground fault you may get lower voltage readings.
Faults in the dock wiring should be corrected, of course. Yet as we have seen, this may be only part of the problem. The only reasonable solution for the marina "boat battery" problem (if you have one) is to use galvanic isolators on the shore power system of the vessel. Transformers eliminate direct electrical contact by transferring electricity magnetically. Some of the more high end marinas these days that cater to large aluminum yachts have such transformers on the dock. This is very expensive since there’s also a great deal of power loss with transformers, so you won’t find many -- if any -- marinas catering to smaller boats like this. It's up to you, the boat owner, to protect yourself. more
Not necessarily, and the reason why is due to a general lack of understanding of what happens in a marina full of boats. After all, this is not an easy thing to understand, and it took a lot of research to find out what was going on here. Yes, the marina’s wiring is involved with all such corrosion problems,
What about marinas with shorts in the system? Won’t they cause corrosion on my boat? In the case of marinas with short circuits in the wiring, usually someone is going to get badly shocked, in addition to which there will be a power drop that will affect everyone. This sort of thing usually gets discovered rather quickly as electric equipment doesn’t function properly and the circuit breakers start popping.
The same advice about jury-rigging wiring applies to DC systems as well AC systems. While you're not going to create an electrocution hazard, it is very easy to take a faultless system and create faults in it. A typical problem starts like this: The owner wants to add a new piece of equipment, but the electric panel is way over there, and the place he wants to install the equipment is way over here. Besides, there are no extra breakers in the panel, and no space in the panel to add another one. To make matters worse, the panel is located in such a way that he couldn't string new wires into it even if he wanted to. So what he does is to find a place where he can tap off an existing circuit, and maybe adds an in-line fuse, stringing wires all over the place in the process. Or maybe he is replacing a piece of equipment that has a faulty circuit, but instead of trying to locate the fault, he just clips off the old wires and strings new ones. This happens a lot, and by the time the boat has a few years on it, it's got cut wires all over the place, many of which are still hot! here
Why it is that there so many builders that install instruments, panels and switches in locations that are going to get wet is something I'll never understand. Oh, I know, you look at those switches and think that they're water proof. Well, you just go look at the back side of the panel and see if you still think so. See if you don't see a lot of corrosion back there. What happens when the back side gets wet? Well, water being a conductor means that these devices will short small amounts of current across the terminals, or to any available ground. This is one of the reasons why you have so many engine instrument failures, and boats have so much of a hardware corrosion problem, and why they have stray current problems, never mind equipment failures. Electrical equipment exposed to weather that is not absolutely water proof is just asking for trouble. [links]
Reverse polarity is not only an electrocution hazard, but can also damage electrical equipment. It is most often found with the three prong spade connectors (household type), but occasionally twist lock connectors as well, particularly in marinas with dilapidated equipment. Never trust the power supply at strange docks, but always check the polarity. When hooking up to strange docks, always check your volt meters to make sure you have adequate voltage. Low voltage is very damaging to electrical equipment. Turn on the stove or water heater and watch what happens to the meter. more
One of the least understood aspects of a boats electrical system, and the most troublesome, is the proper method of grounding. That we often get questions of whether AC or DC electrical equipment should be grounded to the boat's bonding system is illustrative of this point. AC and DC grounding systems are two separate systems, for distinctly different reasons. If you don't understand these systems, you run the distinct risk of creating a disaster. Actually, there are four separate ground systems: DC ground, AC ground, AC grounding (or bond), and the vessel's bonding system. You can add to this lightning and HF radio grounds as well. Do you know the principles of each? Are you sufficiently confused to discourage you from doing your own wiring? I hope so. For unless you understand each thoroughly, you're headed for trouble.
What does bottom paint have to do with electrical systems? Nowadays, with copper based paints, a lot. If, the next time your boat is hauled and you see large ugly burn patterns around all your underwater metals, you got a stray current problem. Copper-based bottom paints react severely to stray current, and serves as a great indicator. Sort of litmus paper for electrical problems.
Many boats have Teak & Holly floorboards ( 5 mm teak and holly with 9 mm ply backing ) fastened to the boat structure with number 8 countersunk SS screws. Over the years, the teak and holly top surface shows … Continue reading →
On occasion, YachtPals will come up with an article regarding a maintenance issue on sailboats that hits the nail right on the head. The latest one has to do with caring for bronze parts on boats. Bronze is used in a variety … Continue reading →
The light fixture above the chart table has two 15 watt light bulbs, one white and one red and switched for independent operation. This fixture was removed during headliner takedown for access to install deck organizers and rope clutches. Upon … Continue reading → [links]
This article originally appeared in the June 2021 issue of 48° North. In the 1890s, Rudolf Diesel created the first compression ignition oil-burning engine, and it was was large, heavy, smoky, and slow turning. While the…
From the April 2021 issue of 48° North. One of the fortunate parts of being a boater in the Pacific Northwest is that the waters of the Salish Sea are open for year-round racing and cruising adventures. That said, most… here
I’ve long been proud of the paint job on my boat. At the same time, I’ve also been a little insecure about it. Everything I know about painting I learned from books, chat boards full of opinionated armchair sailors, or my…