Have you taken an electrical audit?

By: Anita Pavey, Photography by: Anita Pavey

Understanding your RV’s electrical system is a key part of planning your adventures.

Have you taken an electrical audit?
Getting your head around your electrical system and its components can be a bit of a head spin for the uninitiated, but it’s worth exploring, particularly if you travel alone

Trip planning is as much about understanding your rig as anything else. Your choice of mobile lodgings – be it a motorhome, caravan or hybrid – needs to suit your intended purpose, and, for most people, that will involve living off the grid for anything from a few days to a few weeks. After all, who can resist the temptation of free camping or low-cost camping in scenic national parks, at least for a few days?

Your electrical system is paramount to your safety and enjoyment, providing power for lighting, appliances and entertainment. So it stands to reason that you should have a general understanding of its components and how it works. Time for an electrical audit!

Before you gasp in horror, an electrical audit is simply a functional review of what you can and can’t do without 240V power. If your travelling plans are limited to stays in caravan parks, then a basic electrical system will serve you well, but any plans for free camping will require a full rethink.

A quick scan around the inside of your RV should provide an insight about your off-the-grid capabilities. If all you see is 240V outlets and no smaller cigarette or merit-style 12V plugs, then your setup is geared towards caravan parks. But don’t despair – any good auto electrician can resolve this.


With your 240V power lead disconnected and the engine off check all the electrical appliances in your RV to see what works and what doesn’t. Test the lights, stereo, cooker, TV, microwave, electric kettle and other 240V outlets.

The next step is to see how long your power supply will last in typical operating conditions. A battery management system is a huge help in this respect. The better ones will help audit your devices by showing how much power they draw, simply by switching them on one-by-one and checking the readout. The good ones also have a fuel gauge-style display showing how much is left in the tank and the expected range at the current usage rate.

Without a direct 240V source, most 240V plugs won’t work without an appropriately-sized inverter, which converts 12V power to 240V power. If you are using an inverter to run things like a laptop, the inverter will use a small amount of power in the conversion, so make sure you turn it off when it is not in use. In our travels, we found our laptops were quite power hungry, particularly as we had one each!


Most RVs will have a battery box where the electrical hardware is stored. Generally speaking, anything less than two 100Ah deep-cycle batteries isn’t going to be particularly useful for free camping, depending on the duration of your stay, appliances used, ambient temperature and the use of power replenishing tools.

Forget electrical appliances such as the microwave, electric kettle and air-conditioning for free camping. These items are incredibly power hungry and won’t run without a monster inverter and huge battery storage.

Many RVs will use gas-powered fridges for camping which is a good thing, as upright fridges can be take a lot of power when running on battery power alone.


For touring holidays off the grid, a DC-DC charger is an excellent way to get the best utilisation from your battery resources. DC-DC chargers can bump your battery reserves up to a full 100 per cent charge via multi-stage charging. The last 20-30 per cent of charge is completed at a much slower rate, something you can’t do with standard Anderson plug charging. And with a fuller battery, you score better utilisation of your available resources.

Solar power can be a little problematic in that a fixed panel on an RV is only good if you park in the sun, which makes it a warm spot to be. Portable panels can only really be used when you are around, as they can sometimes grow legs and walk when you’re not! Make sure you have a good regulator, such as a Maximum Power Point Tracking (MPPT) unit, as they derive the best output.

Historically, the typical, suitcase-style portable panel kits were bulky and heavy, but these days there are lighter, foldable panels that are much easier to manage. And, unlike a generator, beyond the initial purchase price, there are no ongoing operating costs.

Generators are one of the easiest sources of power. A quick pull of the starter cord and they can be generating power without the need for sun. But most generators run on unleaded fuel, so it means carrying around a supply. They are also bulky and heavy. Add to that the noise and the petrol fumes and there are a few detractors to consider.


Getting your head around your electrical system and its components can be a bit of a head spin for the uninitiated, but it’s worth exploring, particularly if you travel alone. Author Collyn Rivers has written a number of excellent books on understanding RV electrics and using solar power, which can be a huge help in the demystification process.

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The full feature appeared in Caravan World #550 April 2016. Subscribe today for the latest caravan reviews and news every month!