Our Tips to Better Understand the Workings of Motorhome Electrical Systems

By Steve George

September 10, 2019Cars

Equipping your motorhome or caravan with all the 12V accessories you can fit on it can make your outdoor experience much more comfortable and convenient. In the past, 12 volt parts accessories and appliances were much simpler, and you could lit cookers with a match. Heaters and fridges didn’t need 12V power as there were push-button piezo igniters that could power them up. Mains hook-ups were rare and the need for leisure batteries wasn’t there. However, you still had to be careful, if you spent the night reading you were risking a flat battery the next day. Nowadays, however, motorhomes can house an abundance of electrical equipment as a result of the cutting-edge technology they implement.

That being said, in order to power all 12 volt parts accessories and devices, modern motorhomes have two basic electrical systems fitted into them. A mains 230V AC and a 12V DC one. Although both of these have their own distinct purposes, they oftentimes work together with a mains power source to power the more demanding appliances and accessories such as fridges, heaters, how water boilers and battery chargers. Oftentimes, power outlets are provided as well as 12V and mains sockets throughout the interior of the motorhome. Then, there’s the lighting, cooker flame ignitors, fresh water pumps, extractor fans, toilet flush pumps, etc. all of which use 12V power.

At the heart of every motorhome’s 12V electrical system is the leisure battery. Leisure batteries serve the purpose of powering all of your appliances and making sure you don’t get a flat vehicle battery. This device is one of the hardest working parts of the motorhome and it allows you to enjoy the convenience of your 12 volt parts accessories and appliances when away from mains electricity. But in order for the leisure battery to function, it needs to be charged and that can be done in two different ways.

The first charging method is using the vehicle’s base battery charging system – the alternator. The alternator can charge the leisure battery when your vehicle is en route. There’s a split-charge relay that separates the engine’s battery from the leisure battery to make sure the leisure battery doesn’t draw power from the engine battery. The second method only works when your motorhome is connected to a 230V mains power supply. This method involves a mains-powered charger that’s specifically designed to meet the demands of leisure batteries in order to keep them topped off at all times. Some of these chargers can also charge the engine battery once they’re done topping off the leisure battery, while still keeping their functions separated.

If you’re going to be parked at a campsite, you’ll find a bollard that has a mains socket which will supply you with 230V electricity. You can connect the bollard to your motorhome using a hook-up lead, which is basically a heavy-duty version of residential extension leads. The plugs are usually coloured blue, indicating that they’re designed to connect 230V supplies with a maximum load of 16A. The hook-up lead is shrouded so that it’s protected against the elements. One end has female pins and is connected to the externally mounted socket of the motorhome, while the other has male pins and is connected to the bollard.

It’s recommended you plug in the female end into your motorhome before plugging the hook-up lead to the campsite’s bollard. When disconnecting, however, it’s recommended you remove the male end first, as there’s provided protection by a circuit breaker and a residual current device at the bollard. The motorhome has a mains distribution system similar to those you have at home, with a residual current device and circuit breakers protecting the mains circuits of the fridge, battery charger, heater, etc. If a faulty appliance or wiring is detected, the residual current device will disconnect the power.

With the advancements in electrical technology, you can control your motorhome with the use of your smartphone. There are many applications that allow you to control one or multiple functions of your motorhome, like your air-con or heating system. Another technological innovation that has huge benefits for motorhomes is LED lighting. LED lighting lasts longer than conventional lighting solutions and it uses far less energy, which helps preserve your leisure battery. Upgrading to LED lighting fixtures is incredibly easy, and although it might be a larger upfront investment, it’s one that will pay for itself in no time. 

Something else you can also consider is getting solar panels for your motorhome. Solar panels can help charge your leisure batteries at no cost whatsoever. However, you’ll need to also invest in a solar charger that will prevent your battery from getting overcharged. Contrary to popular belief, solar setups aren’t all that expensive nowadays, and they’re extremely easy to fit by yourself on your motorhome. When shopping for a solar panel array, you need to make sure you get one that fits your specific requirements and needs. In other words, make sure the solar panels you get can supply enough energy to keep your battery charged enough for it to power all of your appliances, and that you get a big enough battery to store the necessary amount of energy.

To sum things up, there are many different solutions you can opt for when deciding on how you want to power your motorhome, with leisure batteries most popular one. There’s no right or wrong choice, as everyone’s needs are different, so pick according to yours. There are many guides online on how to pick the right sized battery or solar panels to make sure you have enough energy to power everything you need at the same time.