I realise this has probably been discussed a million times in forum, but can you tell me what Ah battery i should get. we have a jayco expanda and only run the standard lights and fridge etc, any help appreciated. Having our first trip to Maryborough this weekend from Tweed. See you out there.
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Reply By: Grisly - Sunday, Apr 29, 2012 at 19:40

Sunday, Apr 29, 2012 at 19:40

Depends on how long you will need to be self sufficient. A fridge can drain a battery in as little as a few days so a 110 AH battery will be req'd for longer trips.
Another consideration is the type of battery, will you be travelling on corrugation's? as these will kill a normal lead acid battery in as little as 12 months.
Good Luck on your trip.

AnswerID: 484560

Reply By: Trev&Ness B - Sunday, Apr 29, 2012 at 20:24

Sunday, Apr 29, 2012 at 20:24

I have a swan and i run my fridge on gas, its more efficient and the fridge will suck the power from you bats supper quick. I have 2 100ah bats and i run my lights and 12v tv and can last up to a week with no probs. I also run a 120w cheap solar panel and i never drop below 99%. You should also never run your bats below 80% as this will shorten the life off the bats.

AnswerID: 484566

Follow Up By: johno59 - Sunday, Apr 29, 2012 at 21:22

Sunday, Apr 29, 2012 at 21:22
Grisly, i have a 3 way fridge and run it on Gas. Its very efficient and when travelling switch it to 12 volt. As trev states it would suck your battery dry very quickly.I have a 100amp deepcycle battery in my van and although I have not punished it yet, we have camped in the bush for 5 days and ran a couple of lights with led globes SPARINGLY and did not run out of 12 volt power. I also have a 100watt solar panel and am experimenting with it to top up the battery. Some people say u should never let your battery get below %50 some like trev %80. In any case , you should not let it deplete completly as it shortens the life of the batt. Hope this helps johno There is a thread of mineposted tday "connecting 12 volt power to van"which might help also. cheers
FollowupID: 759855

Reply By: The Bantam - Sunday, Apr 29, 2012 at 23:22

Sunday, Apr 29, 2012 at 23:22
The question is what sort of lighst how many and what sort and what size of fridge..and how long do you want it to stand up without a charge.

The simple answer is.......BIGGER than you think.

AnswerID: 484580

Reply By: Member - John and Val - Monday, Apr 30, 2012 at 07:44

Monday, Apr 30, 2012 at 07:44

Depends on "standard lights and fridge etc".

If it's a 3 way fridge - don't run it from the battery at all. It can be run from the vehicle alternator while the engine is running, after that use gas or 240V.

If it's a compressor type fridge such as Engel or Waeco, a 100 Ah deep cycle battery should run it for a couple of days without fully discharging the battery. Batteries should not be discharged more than about 2/3 of their capacity if they are to live long and should be fully recharged asap.

Suggest do an energy budget - determine just what current each of the "standard lights and fridge etc" draws, multiply by the hours per day that each is drawing it. This will give you your demand per day. Assess your charging capability; assume that (unless you have special stuff fitted like a dc-dc charger) your charging from the vehicle averages 5 - 10 amps. Multiply by by engine hours to get a rough idea of what you are putting in. Then you can determine, roughly, your net energy consumption per day, hence how long it will take to use 2/3 of your battery capacity, or how big your battery needs to be to meet the demand.

For a better idea of all that's involved, suggest read Electricity for Camping. The search facility (top right of this screen) will also give lots of good stuff.


J and V
"Not everything that can be counted counts, and not everything that counts can be counted."
- Albert Einstein

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AnswerID: 484595

Reply By: lesterb - Monday, Apr 30, 2012 at 14:22

Monday, Apr 30, 2012 at 14:22
I haven't been caravaning for long but I've learnt a lot from this forum since I started. As a result I have come up with some rules for myself that suit my circumstances.

1. The forum search facility is your friend.
2. Never connect the fridge to the van battery.
3. Always connect the load (led lights, water pump & TV) to the van battery via a low voltage disconnect device which can be a stand alone device or be incorporated in a solar regulator or other charging device and is capable of handling the maximum load current.
4. Replace all incandescent light globes with LEDs.
5. Use an LCD LED TV for lowest current draw.
6. Run the fridge on gas when not travelling or connected to 240v.

By following these rules I hope to complete a trip round the block this year staying in a combination of powered sites and free camping without battery problems.

AnswerID: 484634

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