In this course you will learn everything you need to know about DC systems on boats. Beginning with the basics about current, voltage and resistance, we teach you how to (re-)do all DC wiring on your boat, complying to ISO and ABYC standards.
Boat Electrics 101 - Safe & Reliable DC Systems
A quick welcome and introduction of your teachers and a few words on who this course is for and what to expect.
Get an overview on the contents of this course and the underlying standards.
In this lesson we will cover some dangers and necessary safety precautions to keep in mind before working on your system.
What is electricity and what happens when a current flows? We take a quick look at the behavior of electrons inside metallic conductors.
Learn all you need to know about voltage, the equivalent to pressure in electrical systems.
Ohm's law allows you to calculate how resistance affects voltage given a certain current and vice versa.
Power the product of voltage and current. With two examples you will learn how to calculate the power draw of an appliance.
A quick recap on everything we have learned so far.
Test your knowledge with a quiz!
Learn why it is important to be able to read and draw circuit diagrams.
In this lesson you learn the symbols for wires and wire connections.
What is ground/earth and how is it represented in circuit diagrams?
Get to know the basic symbols for switches and buttons and learn how relays and solenoids work.
Get to know the symbols for resistors and learn about the most common type of resistor on board: the shunt.
How are fuses and circuit breakers represented in circuit diagrams?
Coils mostly occur on boats within transformers. Here you will learn about their basic function and how to represent them.
In this lesson you will get to know a few more symbols for common components in a boat's electrical system.
In the final lesson of the module, you will learn how the components in boat electrics are connected in parallel and in series and how this affects battery capacity and voltage.
Test your knowledge with a Quiz!
Learn about different types of cables and which ones are suitable for use on boats.
Learn what cable colors you can use for what purpose and how to properly label your wiring.
Learn how to choose the proper size for a cable with respect to ampacity and voltage drop.
It is crucial for the system's safety to establish proper connections. In this lesson you will learn how to install terminals in a professional manner.
Proper connections of terminals to bus bars and consumers are vital. Here you learn what makes a professional connection.
In order to prevent fires due to overcurrents and short circuits, protective measures are absolutely crucial. In this lesson you will learn how to choose fuses and circuit breakers and where to install them.
Learn the proper way to install cables in order to protect them from chafing and physical stress
In this lesson we will apply what we have learned in this module to the special case of high output alternators. As we will see, there are quite a lot of things to consider.
Here we show a few more examples of good or bad installations and also what happens in case of a short circuit if no adequate OCP is installed.
Get an overview on what to expect in this important module.
Even though they operate at relatively low voltages, there are significant dangers when dealing with batteries. In this lesson we cover the required safety measures.
In this lesson you will get an overview on the chemistry inside a battery and how lead acid batteries work.
Here we go more into the details of the internal construction and discuss the differences between cranking and deep cycle batteries.
Now it's time to look at different types of lead acid batteries, such as wet cell, AGM, gel-cell and some new innovations.
Learn about the crucial difference between amp-hour and watt-hour efficiency and how to evaluate batteries based on this.
What do the common ratings found batteries (nominal voltage, nominal capacity and cold cranking amp) mean?
In this lesson you will learn what the most common reasons for battery failure or reduced lifespan are and how to avoid them.
Learn how to maximize battery life when installing batteries in serial or parallel.
This lesson will help you decide how much battery capacity you really need for reliable operation and optimal battery lifespan.
Learn how to properly install your battery bank and how to maintain it in order to optimize its performance.
Learn about the most common failure modes with lead acid batteries so mistakes can be avoided.
Through the analogy of a water tank with semi-permeable membranes we explain why it takes a long time to completely top off a lead acid battery.
Learn what an IUoU profile is and how the bulk, absorption and float phases increase battery life.
Learn strategies to reduce charging times and engine hours while at the same time increasing your battery's lifespan.
Learn what to look for when choosing a battery charger, an alternator or when planning on installing renewable energy sources.
Learn about different ways to charge multiple battery banks from a single power source.
Learn about the importance (and challenges) of proper battery monitoring.
A quick recap on what we have learned so far in this module.
In this lesson we introduce the BoatHowTo Boat Electrics Planner which will help us to determine the energy balance on our boat
In this lesson, we will look at all loads on the boat and determine their energy consumption for different scenarios.
To store the energy between charge interval, we have to carefully design our battery banks. In this lesson we look at various options for batteries depending on our calculations from the previous two lessons.
Now we look at the supply side and determine the available charging sources such as shorepower chargers, alternators and renewable energy sources and their required output to keep up with our energy needs.
About the teacher
Jan C. Athenstädt
Dr. Jan Athenstädt guides you through the lessons of this course. The course content has been developed in a joint effort with the most renowned experts on boat electrics from both sides of the Atlantic: Nigel Calder and Michael Herrmann.
I was wondering if you could clarify something for me.
I have installed a battery monitor on my 26-foot sailboat (thank you for the advice on that). My electric panel has 6 main switches than turn on and off six different circuits: one for instruments, one for cabin lights, one for nav lights and so on…
Obviously, with all the main switches off, the battery monitor reads 0 Amps. However, I noticed that when I turn switch number 2 on, the one that controls all the electrics inside the cabin (apart for the nav instruments), but I have nothing turned on, the battery monitor still shows a consumption of 0.4 Amps. This switch turns on/off the circuit that feeds the cabin lighting (LED lighting), the freshwater pump, the bilge pump and little bit more. But with everything off, the battery monitor is showing a usage of 0.4 Amp.
When switch number 2 is on but all the loads that feeds are off there is a “little consumption” from:
– A couple of pilot lights in the panel, the size of the tip of a pen, that tell me that the circuit is on, and that the main battery switch is on.
– The analog fuel tank gauge and its light are on.
– The freshwater pump only comes on when I turn the tap on. Does the pump consume any electricity when there is no water running?
– A pilot light on the FM radio on standby.
Do you think all of that could account for the 0.4Amps?
The thing that makes me think that there could be something wrong is this: when I turn any of the cabin lights (LEDs) on, the battery monitor does not show an increase in Amps being used! It stays at 0.4A. The same when I turn it off.
Do you think there could be something wrong? Any suggestions will be very welcome.
Thank you very much.
By the way, John Neal’s lecture is a fantastic idea. Please bring more people like him, with tons of experience.
Without knowing the exact brands of your components, it’s hard to tell how much they consume in standby mode. What you can do is this:
Disconnect all components from the circuit breaker, turn it on and off (to check for the load of the indication light) and then connect them one at a time and check your monitor battery monitor (of course with all other loads off). This should help you find the culprit pretty soon. While you’re on the boat and charging regularly, 0.4A is not such a big deal. But you definitely want to get rid of this load when you leave the boat…
Let us know if you managed to isolate the consumer!
Thank you Jan. I don’t understand my electric installation very well but I will try to disconnect each one of the loads one by one and see how the battery monitor reading changes. Thank you very much.
Hi Nigel & Jan. Im working my way through these excellent courses and thought that if I get a feedback idea I should put it somewhere before I forget it!
During the lessons I have asked a number of questions and received superb answers. Would it be possible to somehow link a subscriber’s questions and answers so they could pull them all into one place without having to go into each lesson comments section? Secondly, have you thought about grouping themed questions and answers from subscribers into an FAQ section as a resource? You could end up with a great knowledge repository to enhance the site. Best wishes Steve
This is a very good idea! And in a way, that is also prette aligned with what we are currently working on. Nigel just went through all the content and updated the lecture notes based on feedback and comments we got. We will put the updated version online in the coming week. So many of the topics in the comment section will now also be addressed in the lecture notes.
And once we are done with the Diesel course, we will also incorporate them into a re-recorded version of the videos (this will take a while though).
In addition, we plan to discuss some of the questions in greater detail in the next “season” of our “Ask-the-expert” series on YouTube (https://youtube.com/playlist?list=PLAmFyqTkF7VnylrYEgNN32f-m73nXLgEe&feature=shares).