Galvanic Isolator primer
Here’s a potted explanation of what Galvanic Isolators are, and why you very probably need one on YOUR boat……
If your boat is made of metal AND you connect to a shore supply, sometimes called an “Electric Hook-Up”, there is a serious risk of Galvanic Currents causing enormous damage to your boat’s metal hull. A Galvanic isolator can prevent this. When metals are immersed in water, they act as a battery, and when the circuit is completed, small electrical currents flow. We call these currents “Galvanic” or “Corrosion” currents. More about that later. What you need to know is this…
“When Galvanic Current flows, it corrodes metal from the hull of your boat – you really don’t want that”
Although the corrosion currents can be quite small, over a period of months, your boat could shed many many kilograms of its hull, leading to pitting, and even holing. You can often see this along the water line of the boat. It’s well worth checking this right now!
Believe me when I tell you that this is no fairy tale – my own hull lost around half a tonne in weight through corrosion that could have been prevented for just a few pounds with a simple Galvanic isolator (sometimes known as a Zinc Saver).
In fact, there are TWO types of corrosion current that are often mistaken for the same thing. As the hull starts to corrode, pits begin to form in it’s surface and because the pits have a larger surface area than unpitted metal, the corrosion speeds up. Before long, the anodes will have been dissolved away, and your boat is left entirely at the mercy of corrosion – and it’s a boat-killer. Fortunately, the problem is not difficult (or expensive) to resolve. What you need to achieve is to SAFELY break the electrical earth that connects your boat to the shore supply. Note, I say SAFELY. You achieve this with a “Galvanic Isolator”, a simple electronic device that blocks corrosion currents from flowing, while allowing the safety electrical earth to remain intact. There are two types of galvanic isolators:
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A Plug in galvanic isolator that simply connects in-line with your mains connecting cable.
- A Wire in galvanic isolator which is part of your boat’s internal electrical wiring
Learn More…
If you’d like to know even more about Galvanic Isolators, you can read a 2 part article HERE