Confirm my battery is kaput and nothing else ...

May 12, 2014
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I never use the van on battery alone, we're always hooked up somewhere. Last used it for 2 weeks in August and didn't notice anything wrong - after unplugging the van there was no issue with using the mover etc.

It's normally on the drive and plugged in, everything inside the van turned off. I turn the electricity on to charge the battery for 24 hours every 7 days. Last winter the battery was out of the van, in the garage plugged into a CTEK smart trickle charger to keep it topped up. The charger will "report" a faulty battery and didn't give any problems.

Last night whilst packing ready for a weekend away I flipped the "voltage" switch on the master panel and noticed it was only reading 11 volts (reads 13-ish when plugged in). I'd had the electricity on for 24 hours around 2 days ago, and everything turned off in the van since, so battery should be full.

Anyway I know the internal voltage meter is not accurate so I turned the electricity on to charge the battery for an hour then came out with my voltmeter. Across the terminals of the battery it was reading 13.9 volts when the electricity was switched on at the mains, dropping to 13.6 as soon as I switched it off (master switch off in the van and Vision TV aerial disconnected so should be no draw on the battery). One hour later it was reading 12.6 volts at the battery, and 12 hours later this morning it's reading 11 volts.

I think I need a new battery, but it just seems to have degenerated rather quickly. Is that normal, that it seemingly will hold a full charge but quickly lose it? Or do I maybe have electrical gremlins somewhere in the van drawing power when everything is switched off....?
 
Oct 12, 2013
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This happened to me just after Christmas as we went away just after Christmas put it back in the yard for 4 weeks then when I went to get it out for February on the mover the battery was dead ?! perfectly fine before hand . But now I make sure everything is all unplugged and switched off , like you say , the TV booster wire , out , as that was still showing a red light and not even connected up and radio switched off from the source and disconnected.
 
May 24, 2014
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Batteries are funny things, they can take a long time to die, a bit like John Wayne used to do, or they can drop of the perch almost instantly. It does sound as if it is on its way out though. Why not whip it off and go have it tested.
 
Oct 3, 2013
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Tuffty,
You don't say how old the battery is,this can have an effect on battery "charge retention" and performance.From your figures it looks like you need a new battery.With any battery the voltage immediately after charge will be approx the charging voltage,apply a load and the voltage will fall rapidly but not to the levels you experience.
 
May 12, 2014
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I think the battery is the original one which came with the van, would make it 6.5 years old. Anyway took it out and had it on charge in the garage for a few hours, just went in there and there's a very strong smell of rotten eggs, a boiling sound coming from the battery and the CTEK is red hot. New battery time it is!
 
May 12, 2014
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Well it still had the price tag on it, £99.95. I've bought an identical replacement to ensure it fits, Trayna was the cheapest place I could find it and it's now £140 so yeah it probably is that old!
 
Mar 8, 2017
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Just one thought.
Since you only use your caravan on an electric hook-up you do not need a large expensive battery. It may well be that you don't need one at all. You could check that point with the caravan manufacturer. If a battery is needed to provide voltage stabilisation, then a small one of around 20 Ah may suffice.
 
May 7, 2012
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I agree that if you are only using the caravan on hook ups a large battery is not needed. You do refer to a motor mover though so a very small one will not work. I have managed with a 75 AH battery using the mover for mainly putting the caravan back into store. It depends a lot on how much you use the mover.
 
Mar 14, 2005
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Lets put this battery capacity requirement into perspective, because there is a lot of misinformation being banded around.

Virtually all new UK caravans are presently fitted with a mains to DC power supply (PSU) capable of delivering at least 12A. This is enough to run the internal lighting and most of the 12V appliances on its own, but it wont run a caravan mover, and sometimes if a lot of other appliances are already using the power, it can struggle to run a water pump, especially the internal diaphragm ones. To cover these eventualities a rechargeable battery is fitted. The idea is the battery is a power reservoir that can supply the extra current needed when there is a demand that exceeds to PSU's current capacity, and when the demand drops the PSU's excess capacity is used to recharge the battery. Provided the average power demand is less than the PSU's capacity, the PSU will keep the battery well charged.

In terms of how big the battery needs to be does depend on how you use the caravan, but on the basis of the OP's concern with a permanent mains supply, the need for a battery is principally to be able to provide enough current drive to run a caravan mover.

I have previously gone it the detail of of the power needs of a caravan mover, and despite the large current demand when the motors first starts or are stalled, the actual current used is deceptively small and equates to typically less than 2Ah for 5mins of actual running, which is generally more than enough to site a caravan or to couple it up.

On that basis a 10Ah battery should be enough for a holiday, but that is only part of the consideration, and what ever battery is used will also need to have the peak current capacity to start the mover, and that's where a 10Ah leisure battery may not have the cranking capacity, so a slightly larger battery may be needed or consider using a small car battery which should have more than enough cranking capacity.

This solution will only work provided the caravan is used on 24/7 mains hook up site.

If you were considering of grid caravanning you would need a bigger leisure battery.
 
Aug 11, 2018
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I have a 75 Ah leisure battery, it is not big enough to run the mover continuous, it needs a rest after around 15 meters, it would be OK with same size car battery as these can give more current, and when on hook up no reason to use a leisure battery a car battery is good enough.

However I had same as you describe, I think in hind sight father-in-law unplugged and forgot to plug back in, once charged for 24 hours it has run for another year A1. Charging takes time, with the Ctek I would guess around 2 weeks to fully recharge, but to 95% in 2 days.
 
Mar 14, 2005
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ericmark said:
I have a 75 Ah leisure battery, it is not big enough to run the mover continuous, it needs a rest after around 15 meters, it would be OK with same size car battery as these can give more current, and when on hook up no reason to use a leisure battery a car battery is good enough.

However I had same as you describe, I think in hind sight father-in-law unplugged and forgot to plug back in, once charged for 24 hours it has run for another year A1. Charging takes time, with the Ctek I would guess around 2 weeks to fully recharge, but to 95% in 2 days.

Hello Eric,

It sounds to me as though you may have either a poor battery, or a mover that is using far more current than it should.

When Carver first introduced the concept of the caravan mover in the 1990's they took a demonstration unit to Earls Court and the NEC caravan shows. They used a 30M track which included ramps and other typical obstacles which took may be 5min to demonstrate. A full demonstration was planned for every 15Min and the public were allowed to try it out between demonstrations, so you can see it was far more than any normal caravanner would use it in real life.

Concerned that it may exhaust a 110Ah battery they took two, and whilst one was being used the other was being charged. In practice the batteries were only every changed over at the beginning of each new day, and each one lasted a whole day.

Just found this:

http://www.caravanmovershop.ch/docs/movertest/2016-caravan-history.pdf
, I cant believe its over 20 years since the first practical road wheel caravan mover was brought to the public.
 
Nov 11, 2009
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ProfJohnL said:
ericmark said:
I have a 75 Ah leisure battery, it is not big enough to run the mover continuous, it needs a rest after around 15 meters, it would be OK with same size car battery as these can give more current, and when on hook up no reason to use a leisure battery a car battery is good enough.

However I had same as you describe, I think in hind sight father-in-law unplugged and forgot to plug back in, once charged for 24 hours it has run for another year A1. Charging takes time, with the Ctek I would guess around 2 weeks to fully recharge, but to 95% in 2 days.

Hello Eric,

It sounds to me as though you may have either a poor battery, or a mover that is using far more current than it should.

When Carver first introduced the concept of the caravan mover in the 1990's they took a demonstration unit to Earls Court and the NEC caravan shows. They used a 30M track which included ramps and other typical obstacles which took may be 5min to demonstrate. A full demonstration was planned for every 15Min and the public were allowed to try it out between demonstrations, so you can see it was far more than any normal caravanner would use it in real life.

Concerned that it may exhaust a 110Ah battery they took two, and whilst one was being used the other was being charged. In practice the batteries were only every changed over at the beginning of each new day, and each one lasted a whole day.

Just found this:

http://www.caravanmovershop.ch/docs/movertest/2016-caravan-history.pdf
, I cant believe its over 20 years since the first practical road wheel caravan mover was brought to the public.

Prof,
In the words of Wille Nelson " Funny how time slips away" I have today had a similar problem in completing a property questionnaire. "Windows and doors were replaced around 2010" says I. My wife beetled away and found the invoices "No, 2001" At least I got the correct figures just the order was wrong :whistle:
 
Aug 11, 2018
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It is not lack of capacity, after getting caravan into garden I put the battery on charge using a Lidi fixed current battery charger connected to an energy meter, the time taken to recharge, area under the graph shows me I had like you stated used around 10 Ah or less to go from road outside, past the house and into garden at back, quite a long run really.

However clearly the motor mover has a under voltage cut out, so the long straight run, it will stop before complete, don't need to wait long before I can continue likely less than one minute, and once where room is limited and 6" at a time until round the corner there is no problem, neither is there a problem over grass, where I have to stop anyway to correct direction.

I had a 110 Ah battery, old ex-van given to me when it was replaced as being past it for starting van, this would not fail all the way up the drive.

There are two differences, one old van battery was designed to start a car or van so can give out more current, the other is it was bigger, I am sure a 45 Ah car battery or a 110 Ah leisure battery would both work A1, it is not the capacity but how quickly you want the power.

This is the problem with some (not all) valve regulated lead acid, (VRLA) they can give 5A for 3.8 hours with a 20Ah battery, but ask for 100A and it just says no. Put it in parallel with another battery for 3 minutes so some energy can transfer first, and you can jump start quite a large engine, it has all the capacity you need, but not the power.

Maybe the voltage protection is set too high, but from new the 75 Ah battery would cut out on a long run, and the motor mover instructions do say min 95 Ah. 75 Ah does work and has done for three years with no sign of getting any worse, but fact that it does cut out, I would not recommend anyone to use a smaller leisure battery with a motor mover, however could use a smaller vehicle battery.
 
May 12, 2014
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The manual for my mover said the battery needed a CCA rating of at least 700, and in practise it seemed like only the bigger ones had that. I'm also hoping sometime in the next year or so to head off grid, so better to have the option I thought.
 

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