Hi all - another question from someone new to this whole caravanning scene. We will be heading off on our Central Oz trip at the end of August and I need to sort out the following. What is the best set-up for running the 3 way fridge in the van whilst driving? Do we:
1) Run it off the vehicle battery and run the risk of flattening this battery
2) run it off the vehicle battery but install an isolator so that when the vehicle is switched off the power to the fridge is off also and therefore won't flatten the battery
3) Have a dual battery system installed in the vehicle to power the fridge in the van
4) Install a bettery in the van which would run the fridge and be handy if we were staying at unpowered sites.
We won't be running an Engel or Waeco in the car whilst travelling either.
Any advice appreciated!
Cheers,
Wattie
Hi Wattie
The most practical thing to do would be to fit another battery in the van as in option 4 at least you can then have lights etc while you are disconnected from the van. This also reduces the risk of running your car battery flat which is no fun if you are at an isolated spot. There is however a bit more to it than just fitting the battery i have a list of a few things you should consider below.
The battery should be a sealed deep cycle type and fitted in a proper plastic case made for the job and securely mounted and well ventilated..
Any power run from the van battery must be fused as close to the battery as practical.
The wire running throught the car should be around 6mm and only get power when the ignition is on (not accessories). this removes the chance that you could flatten you car battery by accident. You will have to use a relay to achieve this without putting extra load on your ign switch. It must also be fitted with a fuse or circuitbreaker as close as practical to the car battery. you should also run a similar size earth lead from the car battery negative at the same time to ensure a good earth. you can buy twin sheathed cable from most auto electrical outlets. it is just as easy to run two wires as one.
to connect to your van you will need some kind of plug arrangement. Two common types are the Anderson Plug and the 12 pin trailer plugs now available with 7 normal pins and a row of 5 heavy pins fo power etc. debate rages over which is best, jayco now fit the 12 pin as standard but if you already have a plug fitted it may be just a easy to use the Anderson.
you must ensure that power from the van battery cannot get back to the car battery. While the car is starting this could could blow the fuse if the car battery was flat as it would try to use the van battery to start from. you can do this in a number of ways from a simple blocking diode to some very fancy isolation devices.
You may also like to consider a low voltage cutout device for you van battery. This will automaticaly disconnect the battery from the load before it gets flat enough to cause damage to your battery.
You might also like to add a way to trickle charge your van battery when it is plugged into mains power
We have just picked up our expanda and have a battery fitted in the van. Jayco use a Setec unit to achieve most of the items above. There is a wide range of products available in the market at an even wider price range so it would probably pay to talk to your Jayco dealer or an Auto electrican to see what they think. Check your van it may already have some of the abilities built into it's current power unit.