Electrical systems, part 1 – Basics

In this article, you can read about the basics of electrical systems and the concepts of DC and AC. In order for the article not to be so extensive, I have broken out the parts that are about Ohm’s lawHow to use a multimeterMore about alternating…

Electrical systems, part 1 – Ohms law

In this article, you can read about the basic properties of electrical voltage, current, and resistance and Ohm’s law which describes the mathematical relationship between the three quantities.

Electrical systems, part 1 – More about AC

In this article, you can read more about the different forms of AC systems used in Europe and the United States.

Electrical systems, part 1 – The multimeter

In this article, you can read if you use a so-called multimeter (measuring instrument) to measure voltage, resistance, and current. I would like to say that it is your most important measuring instrument to be able to troubleshoot the electrical system.

Electrical system, part 2 – Overview

In this and the next 2 articles, I make a description of an electrical system intended for a long-distance equipped newer boat around 40-60 feet with the possibility to connect 12V, 24V, and 230V equipment. This article provides an overview of the electrical system with its…

Electrical system, part 2 – Cable sizing

When planning an electrical system, it is important to know how thick the cables must be so that they are not heated by the current they are to transport. It can also be good to be able to check if an existing electrical system has correctly…

Electrical system, part 2 – Electrical components

This appendix explains the symbols and other electrical components included in the overview of the electrical system.

Electrical system, part 3 – Subsystems

In this article, I go through the design and function of the main circuits in the electrical subsystems. The article also describes several of the components and circuits of the subsystems in separate appendices. That makes this article the most comprehensive one in the series.

Electrical system, part 3 – Symbol description

This article describes the symbols used in the electrical drawings in Part 3 – Subsystems.

Electrical system, part 3 – Circuits

What is an electrical circuit? An electrical circuit consists of a number of electrical components that are connected to electrical conductors so that they form an electrical circuit. In order for something to happen in the circuit, there must be an electrical energy source connected to…

Eletrical System, part 3 – Data network for electrical equipment

Modern electrical components often have the ability to share information via a data network. In this article, you will learn a little more about what possibilities and limitations they have.

Electrical system, part 3 – Alternator and charging

This article describes how a 12V or 24V DC alternator works and how to charge batteries in different circuits with the same alternator. You can also read about the so-called ”Load dump” and the load on the alternator when charging lithium batteries.

Electrical system, Part 3 – Batteries and charging

There are many different types of rechargeable batteries that can be used in boats. In this article, I go through how the most common types of batteries work, how they can be connected together and how they are charged for the best lifespan.

Electrical system, part 3 – Battery terms

There are several different terms used in the battery context, and in this article, you will find an explanation of the most common terms.

Electrical system, part 3 – Facts about lead batteries

This type of battery has been around for over a hundred years and is a well-proven technology. These batteries are characterized by their high power, i.e. they can deliver a high current in relation to their energy content.

Electrical system, part 3 – Facts lithium-ion batteries

This type of rechargeable battery has existed since the end of the 70s and is based on lithium ions that are stored in molecular layers in the positive and negative terminals of the battery. Hence the name lithium-ion batteries. Compared to lead batteries, they are lighter,…

Electrical system, Part 3 – Battery Comparison

In this table, I have compiled some different characteristics for the most common types of batteries used on board boats today. The figures are approximate as there are some variations between manufacturers. I have also created a table you can use to calculate the life cycle…

Electrical system, part 3 – Battery selection in the subsystems

In this article, I write about a few different things that affect the type of battery and how much battery capacity may be needed for various purposes on board. Here you can find information about the typical consumption of electric energy, how much electricity production is…

Electrical system, part 3 – Connect the battery bank

Often you need more capacity than what is in a battery and this is solved by connecting several batteries in parallel. If the subsystem needs a higher voltage than a battery has, it is solved by connecting batteries in series. In this article, you will learn…

Electrical system, part 3 – Battery chargers

There are several different chargers on board that are used to charge batteries from different energy sources such as the alternator on the main engine, shore power, solar panels, wind turbines, hydro generator, or generator. It is easy to get complicated electrical installations with different chargers…

The electrical system on a sailing boat

The electrical system is one of the most important systems on a boat and as we use more and more electrical equipment on board, the need for electricity increases. In these articles, I have the ambition to write about electrical systems, so that most people who…