The Ultimate Guide to Understanding Electrical Systems in Camper Vans

VW Van

The Ultimate Guide to Understanding Electrical Systems in Camper Vans

In a campervan, there are usually two different 12V electrical systems because they serve two different purposes.

The first system is the vehicle’s electrical system, which is used to power the engine, lights, and other components that are necessary for driving. This system typically uses a 12-volt DC (direct current) power source and is charged by the vehicle’s alternator while the engine is running.

The second system is the living area electrical system, also known as the leisure system. The leisure system powers appliances, lighting, and other devices inside the campervan. This system typically uses a 12-volt DC power source.

Having separate electrical systems is important because it ensures that the vehicle’s electrical needs are met without compromising the power available for the living area. It also allows the living area electrical system to function independently, so you can still use appliances and other devices even when the engine is turned off.

12 Volt Direct Current System

When it comes to building a campervan, one of the most critical systems to consider is the electrical system. Without a reliable power source, you won’t be able to power your lights, appliances, or even charge your devices. One common option for campervan electrical systems is a 12-volt setup, which we will explore in this guide.

A 12-volt system is a extra low voltage (ELV) electrical system that is commonly used in vehicles and boats. In a campervan, it consists of a battery, a charger or chargers, and various components that run on 12 volts DC. The battery is typically a deep-cycle battery, which can withstand multiple charge and discharge cycles without damaging the battery. Deep-cycle batteries are designed to provide a steady supply of power over a long period of time, which is perfect for powering a campervan.

Charging a 12v Battery

A charger is used to recharge the battery when it gets low. There are several ways of charging your leisure batteries, including solar panels, battery to battery chargers, and shore power chargers.

Solar panels are a popular option because they are quiet, efficient, and eco-friendly. They can be mounted on the roof of the campervan and wired directly to the battery.

Battery to battery chargers are another option that uses the vehicle’s alternator to charge the battery while driving.

Finally, shore power chargers are used when the campervan is plugged into an external power source, either at home or on a campsite.


Once you have decided on which way you are going to charge your battery bank, you can begin to add components that run on 12 volts. Some common components include:

1. Lights: LED lights are energy-efficient and can be used for both interior and exterior lighting.

2. Compressor Fridge: A 12-volt compressor fridge can keep your food and drinks cold without the need for propane or external power.

3. Water pump: A 12-volt water pump can be used to pump water from a fresh water tank to your sink or shower.

4. Fans: 12-volt fans can help circulate air in your campervan and keep it cool on hot days.

5. Power outlets: You can install 12-volt power outlets or USB sockets to charge your devices or power other small appliances.


230 Volt Alternating Current System

With van life becoming ever more popular, many people are choosing to outfit their campervans with a 230 Volt Alternating Current electrical system.

Why do I need 230 Volt AC System in my campervan?

A 230V electrical system in a campervan operates on the same voltage as a typical household electrical system. This means that it can power devices and appliances that are designed for use in a home. However, it’s important to note that campervan electrical systems are not the same as household electrical systems and require some specific considerations.

Firstly, campervans require a power source to operate their electrical systems. This can come from a variety of sources including batteries, inverters, or external power hookups. If using external power hookups, it’s important to ensure that the power source is compatible with the campervan’s electrical system.

When it comes to installing a 230V electrical system in a campervan, it’s important to have a good understanding of electrical wiring and safety. We at Tiny Build Electrics can help you with your electrical systems that you wish to install and ensure that the installation is safe and compliant with British wiring regulations.

One important consideration with campervan electrical systems is the size and capacity of the system. The electrical system needs to be able to handle the power requirements of all appliances and devices that will be used in the campervan. It’s important to take into account not only the power consumption of individual devices but also the total power requirements of the campervan’s electrical system as a whole.

Using an inverter to create a 230V system in your campervan

One of the primary advantages of incorporating an inverter into your campervan setup is the ability to access portable power wherever you go. With an inverter, you can convert the direct current (DC) from your leisure batteries into alternating current (AC), which is suitable for powering a wide range of electronic devices. From charging your laptops, smartphones, and cameras to running small appliances such as refrigerators, lights, or fans, an inverter enables you to enjoy the comforts of your tiny home while being immersed in the great outdoors.

When selecting an inverter, safety should always be a top priority. High-quality inverters come equipped with various safety features, including surge protection, voltage regulation, and thermal overload protection. These safeguards prevent damage to your sensitive electronics and ensure a stable power supply. Moreover, reputable inverters undergo rigorous testing and certification processes to meet industry standards. By investing in a reliable inverter and following proper installation guidelines, you can enjoy a worry-free and secure power source during your campervan travels.


To connect your campervan to mains electricity, you’ll need a few essential items:

– To connect your campervan to mains electricity, you’ll need a few essential items:
A high-quality, weatherproof, and durable mains hook-up cable appropriately sized to reach the power outlet on the campsite.

– A suitable adapter plug, if necessary, to match the campsite’s power socket configuration. (If you plan to take your campervan to Europe, you may find you need an adapter plug).

– Cable clips or ties to secure the cable and prevent it from being a tripping hazard.

– A Polarity Tester: A mains polarity tester plug checks the suitability of mains hook up point with regard to earth live and neutral connections.

Note: The supply that you plug your campervan into should have an 30ma type A residual current device (RCD) for additional protection. This device will trip the circuit if it detects an electrical fault, protecting you and your campervan from potential hazards.

Safety Precautions:

While plugging your campervan into mains electricity is relatively straightforward, safety should always be a top priority to:

– Avoid using damaged or worn-out cables and plugs. Regularly inspect and replace them if necessary.

– Keep the cables away from water, sharp objects, and excessive heat sources.

– Use cable clips or ties to secure the cable along the ground, reducing the risk of tripping.

– Never overload the electrical system of your campervan or the campsite’s power supply.

– Always disconnect the mains hook-up cable and switch off the electrical system before driving or leaving the campsite.

– Using a polarity tester, ensure the power supply you’re connecting to is in the same orientation as your camper vans.

Safety & Compliance

An important consideration when selecting and erecting your 230V electrical system for your campervan is the way in which you plan to keep the system and the user safe. Luckily for us, in the UK we have a set of regulations known as the British Standard 7671 and all the vital information and guidelines are in there to help you erect a safe and functional system.


It’s essential to ensure that the system is properly grounded and that the correctly sized circuit breakers and residual current devices are installed to prevent overload and potential electrical fires. Additionally, all wiring should be properly insulated and secured to prevent damage and ensure safe operation.

Confused about any of the above? Book in here with Tom for a consultation call!

Tom Alderdice

Hey, I’m Tom – founder of Tiny Build Electrics

My mission is to help sustainable-minded folks develop their electrical knowledge, giving them the confidence to do their own tiny build electrics.

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