Hi all, need a little help!! we have just returned from our 2nd rally! on the 1st outing the battery went flat within 48 hrs! Which i put down to me checking it while it was hooked up to the tow car ! But the kind people at the rally rescued us & charged the battery & leant us a replacement till it was done! This weekend thinking the battery charged we arrived at site & were shocked to find the meter only showd around 10 volts , we tried to be frugal with what we used but was flat with in 24 hours again!! we got by but the water & loo were a pain without power!
looking around site it seems solar panels are the way forward!! although everyone seems to have different opinions on which size! what does every one else use? and is this the best option or would a generator be better? it would only need to power lights, water pump, loo, electronic ignition 4 cooker.
the battery is 4 yrs old but untill recently we have only ever used the van on sites with EHU!
Could be your battery is on it's last legs. How did you charge it? If you were relying on the 12S to charge it en route then that could explain it as this is a very slow charging process. Better to take the battery home and recharge it.
We rally a lot and find a long weekend is usually not a problem. I carry a 13watt solar panel and in strong sun this can increase the life of the battery by 25%
We always carry a second fully charged battery and always fully charge the batteries at home. Even the caravan charger will only charge to 80% capacity
LegsDownKettleON is quite right. Obviously it seems the battery refuses to hold a charge but you have to recharge it at home with a proper charger as the caravan on board charger just keeps it topped up when in transit so the charge is rather minimal actually as LDKO said.
I have a 13 watt solar panel but when you calculate the input it is only replacing a charge of 1 amp per hour which is really insufficient. I was told that you need at least a 60 watt solar panel so I may invest in one next year hopefully.
I use a 13w suitcase solar panel which is more than enough to top up my battery in my very tiny (and old) caravan. However I do only have 2 LED strip lights that run off 12v which is probably why I find this sufficient!
For a modern caravan I would think you would need at least an 80w panel.
There are a few steps you can take to drastically reduce consumption too. Top of the list is replace all the power hungry halogen bulbs with LEDs. You can get them on eBay for a lot less than a solar panel and use about a 50th of the power.
We had the very same problem last weekend.The battery started dying after 24 hours.I have a 4amp solar panel but I am guessing 4amp doesn't charge anything quickly.I used my generator to top it up but even that didn't make it last much longer.I too think my battery is rubbish.Maybe a spare battery is the answer.
I do find that battery life can be erratic. I have flattened a battery in 24 hours with very little on. I have recharged the battery and the next weekend might get 48 hours out of it or more, despite seemingly using more power.
I do have and use a 5W solar panel to stop the battery going flat when in storage. It works fine for that.
From time to time, I too ponder about whether to buy a much bigger solar panel in the hope that it'll keep the battery charged so that I can do without an ECU for an extended period. If, like us, you use a TV quite a bit when you are way, it just doesn't stack up - I'd need to cover the caravan roof with panels to guarantee that we'd be OK.
The rating of solar panels is based upon the sun shining and the panel being square on to the sun, both horizontally and vertically. The real world average output even on a sunny day is much MUCH less than the nominal rating of the panel - possibly one fifth or less than the nominal output for the expected sunlight hours. On a cloudy day, the output is virtually nothing.
Every time I try to do the sums, I conclude that it just isn't practical (for us). Maybe it's time I looked at small scale wind power. We get lots of wind in the UK and it's not dependent on the sun shining, so maybe it's a better option.
Has anyone seen any caravan friendly 12V wind generators for sale?
There are a few on Ebay. They are a lot cheaper than similar power solar panels although to get the quoted figures will require strong winds (maybe too strong for caravanning.) Looking at the dimensions, they are not small. Nor are they likely to be quiet.
Hi, just a thought, when we enquired about buying an Adria caravan we were told that a battery charger was an optional extra to purchase as they did not come with one as standard equipment, have you checked yours is working okay.
We go rallying a lot without EHU and find the best way to have battery power for a weekend is to take 1 freshly charged battery, and another one in the van, and a 13W suitcase style solar panel. We use one battery and the panel until the lights become dim, then swap to the fresh battery. In summer when the panel is working at full capacity we rarely need to swap mid weekend, but in winter, or after watching some tele we may need to swap.
If we are away for several days/weeks then we take one battery, the panel, and the generator to charge more thoroughly. Some people say that a panel is enough, but you need a jolly big one to charge enough, and they are expensive.
With a voltage down to 10 volts the battery was either wrecked or about to be wrecked. Taking a battery down to this level is extremely damaging and very prompt recharging is needed for any hope of some level of charge retaining recovery.
Given a good battery, a solar panel can be very effective during much of the year even in UK environments; providing its of adequate size, the better type and you take steps not to be profligate with power use.
We use an 85 Watt Kyocera crystalline panel, with a quality Morningstar controller and in all but the winter months this system makes us self-supporting without the need for an EHU.
Whilst it’s correct they don’t yield the full rating of 7 Amps all day. The battery cant take more than 100% charge and usually its not long into the morning before the battery is recharged and the system backs off. Even in cloudy conditions there is still a reasonable charge rarely less than 2 Amps where the battery can take it so it’s quite uninformed to suggest the yield is “virtually nothing”. Clearly if you buy a lowly rated cell then in less than ideal conditions you will get down to a levels of about a third of not much.
For self sufficiency I would advise serious buyers to go for 50 to 55 Watt units with 40 being as low as I feel makes any sense. If its just to stretch out a battery a bit more then anything is better than nothing thought the “degree of that stretch” is greatly increased by larger cells. For servicing a battery in storage very little is usually needed; 5+.
I need to qualify things in saying all our lighting where used for long duration [ie not loo etc] I changed to LEDs; I rewired the radio via an “ignition switch”, and our TV is a low power camping special and we don’t use much evening TV anyway, circ 2 hours per night max. Daytime TV is more than supplied by the cell so my motor and motorcycle coverage is satisfied without any battery drain.
We have a 120 watt roof mounted panel and its brill!
We rally a lot so have no EHU and it charges batteries and
powers tv, DS chargers, dvd etc.
Generators aren't always welcome as they can be rather noisy & intrusive, I would suggest 2 batteries and the biggest solar panel you can afford as the small ones will only trickle charge but not power anything.
We also have a 12 volt tv/dvd player so that helps with low power usage.
good luck & hope to see you on a rally sometime.
Mrs p
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Topic: solar panels!
on the 1st outing the battery went flat within 48 hrs! Which i put down to me checking it while it was hooked up to the tow car 
! But the kind people at the rally rescued us & charged the battery & leant us a replacement till it was done! This weekend thinking the battery charged we arrived at site & were shocked to find the meter only showd around 10 volts 
, we tried to be frugal with what we used but was flat with in 24 hours again!! we got by but the water & loo were a pain without power!
