Rayne Automotive

What is an inverter? 

With any leisure battery set up, you have the option of adding an inverter. An inverter takes the 12V DC power stored in your leisure battery and transforms it up to 240V, then inverts the current from DC to AC. Giving you a 240V AC power supply. Similar to what you have in your 3 pin plugs at home. 

All of our inverters will have at least one, if not two conventional 3 pin plug sockets built into the unit, so when it's wired up and turned on, you can plug your appliance directly into the inverter. 

Do I need an inverter?  The overall verdict is, you will rarely "need" an inverter, but you can add one either at the beginning, or very simply further down the line if there's some 240V items that you always need by your side. Even off grid (such as a laptop).

Do I need an inverter?

Whilst inverters are great, their use is entirely dependant on the battery bank and it's charging capacity. As a result of this, most conversions don't have the battery power required to run big appliances like kettles hair dryers etc. However a small inverter can run the most common things that people like to charge on their travels, a laptop. 

Below we delve into this in a bit more detail. 

We're going to deal with some of the more common things people ask if they can run and a few minimum recommendations on inverter/battery pairings to run these things. 

Big appliances

Big appliances refers, in our opinion, to anything over 500W. This doesn't seem like a lot, but this would be taking around 41 amps out of your leisure battery. That would be enough to flatten the most common leisure batteries in around an hour (each conventional battery has only around 50% of it's rated power in the usable range). 

Our general rule on big appliances is not to use them in a camper conversion, it can be expensive to set up a system to run larger things. However, with the correct set up, anything can be run. 

Small appliances 

Smaller appliances such as laptops, TVs etc are a far more useful and simpler proposition to set up, a simple 300/400W inverter has plenty of capacity to deal with these and can be run from most typical leisure batteries. So if you're looking to take these with you on your travels, then an inverter may be a good idea to add-on to your electrical set up. 

The table below identifies a few common items, their typical wattage (please check your individual appliance as some items vary greatly), and a minimum recommended inverter and battery bank size. Please note, the inverter size is subjective to the component, and the battery bank size is merely to run the item, this does not take into account the duration of the item running and any other components using power in the camper. For more information on the battery bank size you require, check out our other articles.  This simplified view also doesn't take into account the distinction between modified and pure sine wave inverters. Please check our other articles for help with this topic.

Nearly all inverters have an efficiency rating of around 85%, this is due to the power used by the cooling fans and lost as heat during the conversion process. So never run a component right on the limit of your inverter's rated power.  It's also worth noting that turning your inverter off when it's not in use can save a lot of power in the battery as detailed in the table above.

These also are only guidelines based on my own experience, please do not only use this information for designing a set up, always consult the inverter and battery manufacturer to ensure compatibility and then consult the manufacturer of the appliance you intend to use to ensure it's peak wattage is within the inverter's capabilities. You will also need to calculate your desired duration for the component to run and ensure you have enough battery power to achieve this.  We will not be responsible for any set ups, pairings or any issues you might have resulting from your electrical set up. 

The long answer to the question "do I need an inverter?"

The answer is you will rarely "need" an inverter, but for some items it's worth having one in the conversion.  

My general recommendation would always be to get everything you can in 12V format, it's more efficient.

If you're unsure, they are very easy to add retrospectively as a stand alone item, so begin without one, see if there's anything you can't cope without and add one if needs be. It would simply wire directly onto the battery.