After a long period of research, it’s finally time for us to order the components of our electrical system and to install them into our campervan.
Here, we want to provide a simple general overview of our electrical system and its main components.
We will show the diagram sketch of our system and explain some basic terms that come in to play when planning and installing your electrical system.
Disclaimer: because working with electricity can be quite dangerous, we recommend to seek advice of a professional or even have one help you install your system. When installing our setup, we often sought advice of a professional ourselves.
Make a drawing of your future electrical setup
During our research we’ve found that diagrams of electrical systems in a campervan are the easiest and fastest way to comprehend the information we were looking for.
People are visually set. Making drawings of objects goes back to the cavemen. Understanding complicated things through drawings is in our nature!
That is why we chose to start with a diagram of the general components in our electrical system. When starting with the setup of your electrical system, we would recommend for you to start off by sketching it as well. It has helped us a great deal.
To keep things simple in our diagram, we grouped up all 12V appliances and 230V appliances. The red rectangles represent fuses, fuse boxes, or circuit breakers. These are there to protect not only the equipment but also yourself!
Input of electricity via solar panels
In our system, electricity is solely generated by solar energy. We do not plan to stay on campings, so our system therefore does not include a mains electrical hook up. We did not link our car battery to the leisure batteries either, to charge them via the car generator while driving.
Before making this decision, we first calculated the power consumption that we estimate to use when living in the van. You can read all about this calculation in our blog post that explains the process of sizing your battery.
By calculating the total draw on our system we could determine that it is possible for us to solely rely on solar energy generated by our solar panels.
Electricity is thus generated by solar panels on the roof of our van. It is then transported via a fuse to the charge controller. The charge controller determines whether or not the leisure batteries need charging, and acts accordingly. If the batteries need charging, the electricity then travels, via a fuse, to our leisure batteries.
In short: solar radiation → solar panels → charge controller → leisure batteries
Powering your 12V electrical appliances
The charge controller we’ve chosen has the possibility to directly connect to 12V appliances. This helps extend the life of your leisure batteries.
Why? Instead of simultaneously loading and discharging your battery, the appliances are run directly off the power generated by the solar panels when it is sunny outside.
Our 12V appliances are thus connected via a fuse box (containing a fuse for each appliance separately) to the solar charger. This solar charger gets its electricity either from the leisure battery or from the solar panels directly.
In short: Solar panels/leisure battery → Charge controller → 12V appliances
Powering your 230V electrical appliances
Our 230V appliances can of course not directly be connected to our 12V leisure batteries.
The electricity to power our 230V equipment comes from the battery and runs, again via a fuse, to our pure sine wave inverter. The pure sine wave inverter converts the 12V DC to 230V AC. The appliances are then, each via their own fuse, bundled together in a fuse box which is connected to the inverter.
Inverters are generally directly connected to the leisure batteries rather than to the solar charge controller. This has to do with the high current drawn by 230V appliances, which often is too high for the solar charger.
In short: leisure battery → inverter → 230V appliances
Watts, amps, volts
If you’ve never dealt with electricity before, it’s likely that you are not familiar with watts, amps, volts and watt hours. I (Jordy) solely have experience with watts. However, not specifically the type we are dealing with here, but with thermal watts. The amount of watts radiated by the sun, or the Earth, for example.
Terms used in electrics can easily be explained by means of the analogy of water flowing through a tube. Amps, in this analogy, is equal to the volume of water flowing through the pipe.
The water does however not flow through a pipe by itself, for example upwards through your kitchen tap into your sink, but it needs some sort of pressure. This pressure can be compared to volts. Volts can basically be seen as the driving pressure behind electricity. It is thus a measure of the strength with which the electricity is pushed through the circuit.
Lastly, there are watts. Watts can be seen as the total amount of energy. You can think of water wheels that are used to generate energy (electricity) from flowing water.
Amps tell you the amount of energy you have, volts are the speed at which this energy flows through your circuit, and watts can then thus be seen as the resulting product:
Back to our analogy. If you have more water, or in other words more amps, flowing with the same speed, you’ll have more water coming out of the pipe, which relates to more watts.
The same thing happens if you keep the amount of water fixed, but increase the speed, thus the voltage, you’ll also end up with more water which thus again relates to more watts.
But what about watt hours I hear you say
Well, if you understand what watts are at this point, you could derive the meaning of watt hours simply from its name. Watt hours is the amount of watts, or power, that an appliance uses in an hour. This can thus be calculated through:
Watt hours measure the use of energy for a specific period of time, whereas watts can be seen as the rate of power at a specific point in time. 1 watt hour is equivalent to 1 watt expended for one hour.
The next steps
While sketching up our electrical diagram, we calculated the minimum size of our battery and solar panels. We’ve already written about how to go about sizing your leisure battery here.
In our following blog posts we will focus on all other components of our electrical system individually as well as explain how to calculate (yes, calculate and not guess) the minimum thickness of your cables.
Did you like this blog post and want to read more? Click here to go to our main campervan conversion page! Here, you can find a neatly organized list of all blog posts related to our van conversion project.