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Boat Electrical 101

As a precursor on blogs to come I want to start out with a basic electrical blog to begin the foundation. I will start a the heart of the electrical system, the alternator, and go on from there to the battery, battery switches, constant powered items, ending at the engine and house loads.

Many would argue that the battery is the heart of the system but I disagree. Without the alternator the battery is on borrowed time. The alternator’s job is to recharge the battery and to keep up with house loads to keep the battery topped off. The alternator uses power from the battery to create and electromagnet that spins via the engine inside windings to create electricity. That electricity passes through a rectifier and regulator to come out as DC electricity.

Next in line is a battery switch. A battery switch when turns of shuts off all paths of electricity, except to the constant powered items like bilge pumps, bilge alarms, and other various items. A battery switch helps stop any parasitic draws and also serves as a safety function to shut of power to items while being serviced.

Your engine and house loads are items that use electricity. The mechanical Diesel engine only needs electrical power to start. After that it is on its own so to speak. An electronically controlled Diesel engine will need constant power. House loads are your lights, electronics, usb outlets and many other things.

In upcoming blogs and videos I will be getting into how this basic system and be modified and added to to better suit your needs. Products that I will mention or show will only be ones I have experience with and stand behind. Hopefully I will be able to sell them soon. Stay tuned!

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